€•Œsphinx.addnodes”Œdocument”“”)”}”(Œ rawsource”Œ”Œchildren”]”(Œtranslations”Œ LanguagesNode”“”)”}”(hhh]”(hŒpending_xref”“”)”}”(hhh]”Œdocutils.nodes”ŒText”“”ŒChinese (Simplified)”…””}”Œparent”hsbaŒ attributes”}”(Œids”]”Œclasses”]”Œnames”]”Œdupnames”]”Œbackrefs”]”Œ refdomain”Œstd”Œreftype”Œdoc”Œ reftarget”Œ5/translations/zh_CN/admin-guide/device-mapper/dm-raid”Œmodname”NŒ classname”NŒrefexplicit”ˆuŒtagname”hhhubh)”}”(hhh]”hŒChinese (Traditional)”…””}”hh2sbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ5/translations/zh_TW/admin-guide/device-mapper/dm-raid”Œmodname”NŒ classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒItalian”…””}”hhFsbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ5/translations/it_IT/admin-guide/device-mapper/dm-raid”Œmodname”NŒ classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒJapanese”…””}”hhZsbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ5/translations/ja_JP/admin-guide/device-mapper/dm-raid”Œmodname”NŒ classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒKorean”…””}”hhnsbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ5/translations/ko_KR/admin-guide/device-mapper/dm-raid”Œmodname”NŒ classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒSpanish”…””}”hh‚sbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ5/translations/sp_SP/admin-guide/device-mapper/dm-raid”Œmodname”NŒ classname”NŒrefexplicit”ˆuh1hhhubeh}”(h]”h ]”h"]”h$]”h&]”Œcurrent_language”ŒEnglish”uh1h hhŒ _document”hŒsource”NŒline”NubhŒsection”“”)”}”(hhh]”(hŒtitle”“”)”}”(hŒdm-raid”h]”hŒdm-raid”…””}”(hh¨hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hh£hžhhŸŒO/var/lib/git/docbuild/linux/Documentation/admin-guide/device-mapper/dm-raid.rst”h KubhŒ paragraph”“”)”}”(hŒ–The device-mapper RAID (dm-raid) target provides a bridge from DM to MD. It allows the MD RAID drivers to be accessed using a device-mapper interface.”h]”hŒ–The device-mapper RAID (dm-raid) target provides a bridge from DM to MD. It allows the MD RAID drivers to be accessed using a device-mapper interface.”…””}”(hh¹hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubh¢)”}”(hhh]”(h§)”}”(hŒMapping Table Interface”h]”hŒMapping Table Interface”…””}”(hhÊhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hhÇhžhhŸh¶h Kubh¸)”}”(hŒDThe target is named "raid" and it accepts the following parameters::”h]”hŒGThe target is named â€œraidâ€ and it accepts the following parameters:”…””}”(hhØhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KhhÇhžhubhŒ literal_block”“”)”}”(hŒl <#raid_params> \ <#raid_devs> [.. ]”h]”hŒl <#raid_params> \ <#raid_devs> [.. ]”…””}”hhèsbah}”(h]”h ]”h"]”h$]”h&]”Œ xml:space”Œpreserve”uh1hæhŸh¶h KhhÇhžhubh¸)”}”(hŒ:”h]”hŒ:”…””}”(hhøhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KhhÇhžhubhŒblock_quote”“”)”}”(hXÖ============= =============================================================== raid0 RAID0 striping (no resilience) raid1 RAID1 mirroring raid4 RAID4 with dedicated last parity disk raid5_n RAID5 with dedicated last parity disk supporting takeover Same as raid4 - Transitory layout raid5_la RAID5 left asymmetric - rotating parity 0 with data continuation raid5_ra RAID5 right asymmetric - rotating parity N with data continuation raid5_ls RAID5 left symmetric - rotating parity 0 with data restart raid5_rs RAID5 right symmetric - rotating parity N with data restart raid6_zr RAID6 zero restart - rotating parity zero (left-to-right) with data restart raid6_nr RAID6 N restart - rotating parity N (right-to-left) with data restart raid6_nc RAID6 N continue - rotating parity N (right-to-left) with data continuation raid6_n_6 RAID6 with dedicate parity disks - parity and Q-syndrome on the last 2 disks; layout for takeover from/to raid4/raid5_n raid6_la_6 Same as "raid_la" plus dedicated last Q-syndrome disk - layout for takeover from raid5_la from/to raid6 raid6_ra_6 Same as "raid5_ra" dedicated last Q-syndrome disk - layout for takeover from raid5_ra from/to raid6 raid6_ls_6 Same as "raid5_ls" dedicated last Q-syndrome disk - layout for takeover from raid5_ls from/to raid6 raid6_rs_6 Same as "raid5_rs" dedicated last Q-syndrome disk - layout for takeover from raid5_rs from/to raid6 raid10 Various RAID10 inspired algorithms chosen by additional params (see raid10_format and raid10_copies below) - RAID10: Striped Mirrors (aka 'Striping on top of mirrors') - RAID1E: Integrated Adjacent Stripe Mirroring - RAID1E: Integrated Offset Stripe Mirroring - and other similar RAID10 variants ============= =============================================================== Reference: Chapter 4 of https://www.snia.org/sites/default/files/SNIA_DDF_Technical_Position_v2.0.pdf ”h]”(hŒtable”“”)”}”(hhh]”hŒtgroup”“”)”}”(hhh]”(hŒcolspec”“”)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”K uh1jhjubj)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”K?uh1jhjubhŒtbody”“”)”}”(hhh]”(hŒrow”“”)”}”(hhh]”(hŒentry”“”)”}”(hhh]”h¸)”}”(hŒraid0”h]”hŒraid0”…””}”(hj;hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj8ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj3ubj7)”}”(hhh]”h¸)”}”(hŒRAID0 striping (no resilience)”h]”hŒRAID0 striping (no resilience)”…””}”(hjRhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KhjOubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj3ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒraid1”h]”hŒraid1”…””}”(hjrhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khjoubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjlubj7)”}”(hhh]”h¸)”}”(hŒRAID1 mirroring”h]”hŒRAID1 mirroring”…””}”(hj‰hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj†ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjlubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒraid4”h]”hŒraid4”…””}”(hj©hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj¦ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj£ubj7)”}”(hhh]”h¸)”}”(hŒ%RAID4 with dedicated last parity disk”h]”hŒ%RAID4 with dedicated last parity disk”…””}”(hjÀhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj½ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj£ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒraid5_n”h]”hŒraid5_n”…””}”(hjàhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KhjÝubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjÚubj7)”}”(hhh]”(h¸)”}”(hŒGRAID5 with dedicated last parity disk supporting takeover Same as raid4”h]”hŒGRAID5 with dedicated last parity disk supporting takeover Same as raid4”…””}”(hj÷hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KhjôubhŒbullet_list”“”)”}”(hhh]”hŒ list_item”“”)”}”(hŒTransitory layout”h]”h¸)”}”(hjh]”hŒTransitory layout”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khjubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjubah}”(h]”h ]”h"]”h$]”h&]”Œbullet”Œ-”uh1jhŸh¶h Khjôubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hjÚubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒraid5_la”h]”hŒraid5_la”…””}”(hj=hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj:ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj7ubj7)”}”(hhh]”(h¸)”}”(hŒRAID5 left asymmetric”h]”hŒRAID5 left asymmetric”…””}”(hjThžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KhjQubj)”}”(hhh]”j)”}”(hŒ(rotating parity 0 with data continuation”h]”h¸)”}”(hjgh]”hŒ(rotating parity 0 with data continuation”…””}”(hjihžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khjeubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjbubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h KhjQubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hj7ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒraid5_ra”h]”hŒraid5_ra”…””}”(hj”hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj‘ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjŽubj7)”}”(hhh]”(h¸)”}”(hŒRAID5 right asymmetric”h]”hŒRAID5 right asymmetric”…””}”(hj«hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj¨ubj)”}”(hhh]”j)”}”(hŒ(rotating parity N with data continuation”h]”h¸)”}”(hj¾h]”hŒ(rotating parity N with data continuation”…””}”(hjÀhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K hj¼ubah}”(h]”h ]”h"]”h$]”h&]”uh1j hj¹ubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h K hj¨ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hjŽubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒraid5_ls”h]”hŒraid5_ls”…””}”(hjëhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K!hjèubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjåubj7)”}”(hhh]”(h¸)”}”(hŒRAID5 left symmetric”h]”hŒRAID5 left symmetric”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K!hjÿubj)”}”(hhh]”j)”}”(hŒ#rotating parity 0 with data restart”h]”h¸)”}”(hjh]”hŒ#rotating parity 0 with data restart”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K#hjubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h K#hjÿubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hjåubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒraid5_rs”h]”hŒraid5_rs”…””}”(hjBhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K$hj?ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj<ubj7)”}”(hhh]”(h¸)”}”(hŒRAID5 right symmetric”h]”hŒRAID5 right symmetric”…””}”(hjYhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K$hjVubj)”}”(hhh]”j)”}”(hŒ#rotating parity N with data restart”h]”h¸)”}”(hjlh]”hŒ#rotating parity N with data restart”…””}”(hjnhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K&hjjubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjgubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h K&hjVubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hj<ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒraid6_zr”h]”hŒraid6_zr”…””}”(hj™hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K'hj–ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj“ubj7)”}”(hhh]”(h¸)”}”(hŒRAID6 zero restart”h]”hŒRAID6 zero restart”…””}”(hj°hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K'hjubj)”}”(hhh]”j)”}”(hŒ6rotating parity zero (left-to-right) with data restart”h]”h¸)”}”(hjÃh]”hŒ6rotating parity zero (left-to-right) with data restart”…””}”(hjÅhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K)hjÁubah}”(h]”h ]”h"]”h$]”h&]”uh1j hj¾ubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h K)hjubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hj“ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒraid6_nr”h]”hŒraid6_nr”…””}”(hjðhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K*hjíubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjêubj7)”}”(hhh]”(h¸)”}”(hŒRAID6 N restart”h]”hŒRAID6 N restart”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K*hjubj)”}”(hhh]”j)”}”(hŒ3rotating parity N (right-to-left) with data restart”h]”h¸)”}”(hjh]”hŒ3rotating parity N (right-to-left) with data restart”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K,hjubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h K,hjubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hjêubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒraid6_nc”h]”hŒraid6_nc”…””}”(hjGhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K-hjDubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjAubj7)”}”(hhh]”(h¸)”}”(hŒRAID6 N continue”h]”hŒRAID6 N continue”…””}”(hj^hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K-hj[ubj)”}”(hhh]”j)”}”(hŒ8rotating parity N (right-to-left) with data continuation”h]”h¸)”}”(hjqh]”hŒ8rotating parity N (right-to-left) with data continuation”…””}”(hjshžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K/hjoubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjlubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h K/hj[ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hjAubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ raid6_n_6”h]”hŒ raid6_n_6”…””}”(hjžhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K0hj›ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj˜ubj7)”}”(hhh]”(h¸)”}”(hŒ RAID6 with dedicate parity disks”h]”hŒ RAID6 with dedicate parity disks”…””}”(hjµhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K0hj²ubj)”}”(hhh]”j)”}”(hŒTparity and Q-syndrome on the last 2 disks; layout for takeover from/to raid4/raid5_n”h]”h¸)”}”(hŒTparity and Q-syndrome on the last 2 disks; layout for takeover from/to raid4/raid5_n”h]”hŒTparity and Q-syndrome on the last 2 disks; layout for takeover from/to raid4/raid5_n”…””}”(hjÊhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K2hjÆubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjÃubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h K2hj²ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hj˜ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ raid6_la_6”h]”hŒ raid6_la_6”…””}”(hjöhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K4hjóubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjðubj7)”}”(hhh]”(h¸)”}”(hŒ5Same as "raid_la" plus dedicated last Q-syndrome disk”h]”hŒ9Same as â€œraid_laâ€ plus dedicated last Q-syndrome disk”…””}”(hj hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K4hj ubj)”}”(hhh]”j)”}”(hŒ/layout for takeover from raid5_la from/to raid6”h]”h¸)”}”(hj h]”hŒ/layout for takeover from raid5_la from/to raid6”…””}”(hj"hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K6hjubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h K6hj ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hjðubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ raid6_ra_6”h]”hŒ raid6_ra_6”…””}”(hjMhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K7hjJubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjGubj7)”}”(hhh]”(h¸)”}”(hŒ1Same as "raid5_ra" dedicated last Q-syndrome disk”h]”hŒ5Same as â€œraid5_raâ€ dedicated last Q-syndrome disk”…””}”(hjdhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K7hjaubj)”}”(hhh]”j)”}”(hŒ/layout for takeover from raid5_ra from/to raid6”h]”h¸)”}”(hjwh]”hŒ/layout for takeover from raid5_ra from/to raid6”…””}”(hjyhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K9hjuubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjrubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h K9hjaubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hjGubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ raid6_ls_6”h]”hŒ raid6_ls_6”…””}”(hj¤hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K:hj¡ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjžubj7)”}”(hhh]”(h¸)”}”(hŒ1Same as "raid5_ls" dedicated last Q-syndrome disk”h]”hŒ5Same as â€œraid5_lsâ€ dedicated last Q-syndrome disk”…””}”(hj»hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K:hj¸ubj)”}”(hhh]”j)”}”(hŒ/layout for takeover from raid5_ls from/to raid6”h]”h¸)”}”(hjÎh]”hŒ/layout for takeover from raid5_ls from/to raid6”…””}”(hjÐhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KRAID10: Striped Mirrors (aka â€˜Striping on top of mirrorsâ€™)”…””}”(hj~hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KChjzubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjwubj)”}”(hŒ,RAID1E: Integrated Adjacent Stripe Mirroring”h]”h¸)”}”(hj“h]”hŒ,RAID1E: Integrated Adjacent Stripe Mirroring”…””}”(hj•hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KDhj‘ubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjwubj)”}”(hŒ*RAID1E: Integrated Offset Stripe Mirroring”h]”h¸)”}”(hjªh]”hŒ*RAID1E: Integrated Offset Stripe Mirroring”…””}”(hj¬hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KEhj¨ubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjwubj)”}”(hŒ!and other similar RAID10 variants”h]”h¸)”}”(hjÁh]”hŒ!and other similar RAID10 variants”…””}”(hjÃhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KFhj¿ubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjwubeh}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h KChjfubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hjLubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj.ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j,hjubeh}”(h]”h ]”h"]”h$]”h&]”Œcols”Kuh1jhjubah}”(h]”h ]”h"]”h$]”h&]”uh1jhjubh¸)”}”(hŒeReference: Chapter 4 of https://www.snia.org/sites/default/files/SNIA_DDF_Technical_Position_v2.0.pdf”h]”(hŒReference: Chapter 4 of ”…””}”(hjûhžhhŸNh NubhŒ reference”“”)”}”(hŒMhttps://www.snia.org/sites/default/files/SNIA_DDF_Technical_Position_v2.0.pdf”h]”hŒMhttps://www.snia.org/sites/default/files/SNIA_DDF_Technical_Position_v2.0.pdf”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”Œrefuri”juh1jhjûubeh}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KIhjubeh}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h KhhÇhžhubh¸)”}”(hŒ5<#raid_params>: The number of parameters that follow.”h]”hŒ5<#raid_params>: The number of parameters that follow.”…””}”(hj hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KLhhÇhžhubh¸)”}”(hŒ consists of”h]”hŒ consists of”…””}”(hj.hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KNhhÇhžhubj)”}”(hX†Mandatory parameters: : Chunk size in sectors. This parameter is often known as "stripe size". It is the only mandatory parameter and is placed first. followed by optional parameters (in any order): [sync|nosync] Force or prevent RAID initialization. [rebuild ] Rebuild drive number 'idx' (first drive is 0). [daemon_sleep ] Interval between runs of the bitmap daemon that clear bits. A longer interval means less bitmap I/O but resyncing after a failure is likely to take longer. [min_recovery_rate ] Throttle RAID initialization [max_recovery_rate ] Throttle RAID initialization [write_mostly ] Mark drive index 'idx' write-mostly. [max_write_behind ] See '--write-behind=' (man mdadm) [stripe_cache ] Stripe cache size (RAID 4/5/6 only) [region_size ] The region_size multiplied by the number of regions is the logical size of the array. The bitmap records the device synchronisation state for each region. [raid10_copies <# copies>], [raid10_format ] These two options are used to alter the default layout of a RAID10 configuration. The number of copies is can be specified, but the default is 2. There are also three variations to how the copies are laid down - the default is "near". Near copies are what most people think of with respect to mirroring. If these options are left unspecified, or 'raid10_copies 2' and/or 'raid10_format near' are given, then the layouts for 2, 3 and 4 devices are: ======== ========== ============== 2 drives 3 drives 4 drives ======== ========== ============== A1 A1 A1 A1 A2 A1 A1 A2 A2 A2 A2 A2 A3 A3 A3 A3 A4 A4 A3 A3 A4 A4 A5 A5 A5 A6 A6 A4 A4 A5 A6 A6 A7 A7 A8 A8 .. .. .. .. .. .. .. .. .. ======== ========== ============== The 2-device layout is equivalent 2-way RAID1. The 4-device layout is what a traditional RAID10 would look like. The 3-device layout is what might be called a 'RAID1E - Integrated Adjacent Stripe Mirroring'. If 'raid10_copies 2' and 'raid10_format far', then the layouts for 2, 3 and 4 devices are: ======== ============ =================== 2 drives 3 drives 4 drives ======== ============ =================== A1 A2 A1 A2 A3 A1 A2 A3 A4 A3 A4 A4 A5 A6 A5 A6 A7 A8 A5 A6 A7 A8 A9 A9 A10 A11 A12 .. .. .. .. .. .. .. .. .. A2 A1 A3 A1 A2 A2 A1 A4 A3 A4 A3 A6 A4 A5 A6 A5 A8 A7 A6 A5 A9 A7 A8 A10 A9 A12 A11 .. .. .. .. .. .. .. .. .. ======== ============ =================== If 'raid10_copies 2' and 'raid10_format offset', then the layouts for 2, 3 and 4 devices are: ======== ========== ================ 2 drives 3 drives 4 drives ======== ========== ================ A1 A2 A1 A2 A3 A1 A2 A3 A4 A2 A1 A3 A1 A2 A2 A1 A4 A3 A3 A4 A4 A5 A6 A5 A6 A7 A8 A4 A3 A6 A4 A5 A6 A5 A8 A7 A5 A6 A7 A8 A9 A9 A10 A11 A12 A6 A5 A9 A7 A8 A10 A9 A12 A11 .. .. .. .. .. .. .. .. .. ======== ========== ================ Here we see layouts closely akin to 'RAID1E - Integrated Offset Stripe Mirroring'. [delta_disks ] The delta_disks option value (-251 < N < +251) triggers device removal (negative value) or device addition (positive value) to any reshape supporting raid levels 4/5/6 and 10. RAID levels 4/5/6 allow for addition of devices (metadata and data device tuple), raid10_near and raid10_offset only allow for device addition. raid10_far does not support any reshaping at all. A minimum of devices have to be kept to enforce resilience, which is 3 devices for raid4/5 and 4 devices for raid6. [data_offset ] This option value defines the offset into each data device where the data starts. This is used to provide out-of-place reshaping space to avoid writing over data while changing the layout of stripes, hence an interruption/crash may happen at any time without the risk of losing data. E.g. when adding devices to an existing raid set during forward reshaping, the out-of-place space will be allocated at the beginning of each raid device. The kernel raid4/5/6/10 MD personalities supporting such device addition will read the data from the existing first stripes (those with smaller number of stripes) starting at data_offset to fill up a new stripe with the larger number of stripes, calculate the redundancy blocks (CRC/Q-syndrome) and write that new stripe to offset 0. Same will be applied to all N-1 other new stripes. This out-of-place scheme is used to change the RAID type (i.e. the allocation algorithm) as well, e.g. changing from raid5_ls to raid5_n. [journal_dev ] This option adds a journal device to raid4/5/6 raid sets and uses it to close the 'write hole' caused by the non-atomic updates to the component devices which can cause data loss during recovery. The journal device is used as writethrough thus causing writes to be throttled versus non-journaled raid4/5/6 sets. Takeover/reshape is not possible with a raid4/5/6 journal device; it has to be deconfigured before requesting these. [journal_mode ] This option sets the caching mode on journaled raid4/5/6 raid sets (see 'journal_dev ' above) to 'writethrough' or 'writeback'. If 'writeback' is selected the journal device has to be resilient and must not suffer from the 'write hole' problem itself (e.g. use raid1 or raid10) to avoid a single point of failure. ”h]”hŒdefinition_list”“”)”}”(hhh]”(hŒdefinition_list_item”“”)”}”(hŒÏMandatory parameters: : Chunk size in sectors. This parameter is often known as "stripe size". It is the only mandatory parameter and is placed first. ”h]”(hŒterm”“”)”}”(hŒMandatory parameters:”h]”hŒMandatory parameters:”…””}”(hjMhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h KThjGubhŒ definition”“”)”}”(hhh]”jA)”}”(hhh]”jF)”}”(hŒ: Chunk size in sectors. This parameter is often known as "stripe size". It is the only mandatory parameter and is placed first. ”h]”(jL)”}”(hŒ :”h]”hŒ :”…””}”(hjghžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h KThjcubj\)”}”(hhh]”h¸)”}”(hŒ€Chunk size in sectors. This parameter is often known as "stripe size". It is the only mandatory parameter and is placed first.”h]”hŒ„Chunk size in sectors. This parameter is often known as â€œstripe sizeâ€. It is the only mandatory parameter and is placed first.”…””}”(hjxhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KRhjuubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjcubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h KThj`ubah}”(h]”h ]”h"]”h$]”h&]”uh1j@hj]ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjGubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h KThjBubjF)”}”(hXÞfollowed by optional parameters (in any order): [sync|nosync] Force or prevent RAID initialization. [rebuild ] Rebuild drive number 'idx' (first drive is 0). [daemon_sleep ] Interval between runs of the bitmap daemon that clear bits. A longer interval means less bitmap I/O but resyncing after a failure is likely to take longer. [min_recovery_rate ] Throttle RAID initialization [max_recovery_rate ] Throttle RAID initialization [write_mostly ] Mark drive index 'idx' write-mostly. [max_write_behind ] See '--write-behind=' (man mdadm) [stripe_cache ] Stripe cache size (RAID 4/5/6 only) [region_size ] The region_size multiplied by the number of regions is the logical size of the array. The bitmap records the device synchronisation state for each region. [raid10_copies <# copies>], [raid10_format ] These two options are used to alter the default layout of a RAID10 configuration. The number of copies is can be specified, but the default is 2. There are also three variations to how the copies are laid down - the default is "near". Near copies are what most people think of with respect to mirroring. If these options are left unspecified, or 'raid10_copies 2' and/or 'raid10_format near' are given, then the layouts for 2, 3 and 4 devices are: ======== ========== ============== 2 drives 3 drives 4 drives ======== ========== ============== A1 A1 A1 A1 A2 A1 A1 A2 A2 A2 A2 A2 A3 A3 A3 A3 A4 A4 A3 A3 A4 A4 A5 A5 A5 A6 A6 A4 A4 A5 A6 A6 A7 A7 A8 A8 .. .. .. .. .. .. .. .. .. ======== ========== ============== The 2-device layout is equivalent 2-way RAID1. The 4-device layout is what a traditional RAID10 would look like. The 3-device layout is what might be called a 'RAID1E - Integrated Adjacent Stripe Mirroring'. If 'raid10_copies 2' and 'raid10_format far', then the layouts for 2, 3 and 4 devices are: ======== ============ =================== 2 drives 3 drives 4 drives ======== ============ =================== A1 A2 A1 A2 A3 A1 A2 A3 A4 A3 A4 A4 A5 A6 A5 A6 A7 A8 A5 A6 A7 A8 A9 A9 A10 A11 A12 .. .. .. .. .. .. .. .. .. A2 A1 A3 A1 A2 A2 A1 A4 A3 A4 A3 A6 A4 A5 A6 A5 A8 A7 A6 A5 A9 A7 A8 A10 A9 A12 A11 .. .. .. .. .. .. .. .. .. ======== ============ =================== If 'raid10_copies 2' and 'raid10_format offset', then the layouts for 2, 3 and 4 devices are: ======== ========== ================ 2 drives 3 drives 4 drives ======== ========== ================ A1 A2 A1 A2 A3 A1 A2 A3 A4 A2 A1 A3 A1 A2 A2 A1 A4 A3 A3 A4 A4 A5 A6 A5 A6 A7 A8 A4 A3 A6 A4 A5 A6 A5 A8 A7 A5 A6 A7 A8 A9 A9 A10 A11 A12 A6 A5 A9 A7 A8 A10 A9 A12 A11 .. .. .. .. .. .. .. .. .. ======== ========== ================ Here we see layouts closely akin to 'RAID1E - Integrated Offset Stripe Mirroring'. [delta_disks ] The delta_disks option value (-251 < N < +251) triggers device removal (negative value) or device addition (positive value) to any reshape supporting raid levels 4/5/6 and 10. RAID levels 4/5/6 allow for addition of devices (metadata and data device tuple), raid10_near and raid10_offset only allow for device addition. raid10_far does not support any reshaping at all. A minimum of devices have to be kept to enforce resilience, which is 3 devices for raid4/5 and 4 devices for raid6. [data_offset ] This option value defines the offset into each data device where the data starts. This is used to provide out-of-place reshaping space to avoid writing over data while changing the layout of stripes, hence an interruption/crash may happen at any time without the risk of losing data. E.g. when adding devices to an existing raid set during forward reshaping, the out-of-place space will be allocated at the beginning of each raid device. The kernel raid4/5/6/10 MD personalities supporting such device addition will read the data from the existing first stripes (those with smaller number of stripes) starting at data_offset to fill up a new stripe with the larger number of stripes, calculate the redundancy blocks (CRC/Q-syndrome) and write that new stripe to offset 0. Same will be applied to all N-1 other new stripes. This out-of-place scheme is used to change the RAID type (i.e. the allocation algorithm) as well, e.g. changing from raid5_ls to raid5_n. [journal_dev ] This option adds a journal device to raid4/5/6 raid sets and uses it to close the 'write hole' caused by the non-atomic updates to the component devices which can cause data loss during recovery. The journal device is used as writethrough thus causing writes to be throttled versus non-journaled raid4/5/6 sets. Takeover/reshape is not possible with a raid4/5/6 journal device; it has to be deconfigured before requesting these. [journal_mode ] This option sets the caching mode on journaled raid4/5/6 raid sets (see 'journal_dev ' above) to 'writethrough' or 'writeback'. If 'writeback' is selected the journal device has to be resilient and must not suffer from the 'write hole' problem itself (e.g. use raid1 or raid10) to avoid a single point of failure. ”h]”(jL)”}”(hŒ/followed by optional parameters (in any order):”h]”hŒ/followed by optional parameters (in any order):”…””}”(hj¨hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h K×hj¤ubj\)”}”(hhh]”jA)”}”(hhh]”(jF)”}”(hŒ4[sync|nosync] Force or prevent RAID initialization. ”h]”(jL)”}”(hŒ [sync|nosync]”h]”hŒ [sync|nosync]”…””}”(hjÀhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h KXhj¼ubj\)”}”(hhh]”h¸)”}”(hŒ%Force or prevent RAID initialization.”h]”hŒ%Force or prevent RAID initialization.”…””}”(hjÑhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KXhjÎubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hj¼ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h KXhj¹ubjF)”}”(hŒ?[rebuild ] Rebuild drive number 'idx' (first drive is 0). ”h]”(jL)”}”(hŒ[rebuild ]”h]”hŒ[rebuild ]”…””}”(hjïhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h K[hjëubj\)”}”(hhh]”h¸)”}”(hŒ.Rebuild drive number 'idx' (first drive is 0).”h]”hŒ2Rebuild drive number â€˜idxâ€™ (first drive is 0).”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K[hjýubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjëubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h K[hj¹ubjF)”}”(hŒ±[daemon_sleep ] Interval between runs of the bitmap daemon that clear bits. A longer interval means less bitmap I/O but resyncing after a failure is likely to take longer. ”h]”(jL)”}”(hŒ[daemon_sleep ]”h]”hŒ[daemon_sleep ]”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h K`hjubj\)”}”(hhh]”h¸)”}”(hŒœInterval between runs of the bitmap daemon that clear bits. A longer interval means less bitmap I/O but resyncing after a failure is likely to take longer.”h]”hŒœInterval between runs of the bitmap daemon that clear bits. A longer interval means less bitmap I/O but resyncing after a failure is likely to take longer.”…””}”(hj/hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K^hj,ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h K`hj¹ubjF)”}”(hŒ>[min_recovery_rate ] Throttle RAID initialization”h]”(jL)”}”(hŒ![min_recovery_rate ]”h]”hŒ![min_recovery_rate ]”…””}”(hjMhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h KbhjIubj\)”}”(hhh]”h¸)”}”(hŒThrottle RAID initialization”h]”hŒThrottle RAID initialization”…””}”(hj^hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kchj[ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjIubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h Kbhj¹ubjF)”}”(hŒ>[max_recovery_rate ] Throttle RAID initialization”h]”(jL)”}”(hŒ![max_recovery_rate ]”h]”hŒ![max_recovery_rate ]”…””}”(hj|hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h Kdhjxubj\)”}”(hhh]”h¸)”}”(hŒThrottle RAID initialization”h]”hŒThrottle RAID initialization”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KehjŠubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjxubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h Kdhj¹ubjF)”}”(hŒ9[write_mostly ] Mark drive index 'idx' write-mostly.”h]”(jL)”}”(hŒ[write_mostly ]”h]”hŒ[write_mostly ]”…””}”(hj«hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h Kfhj§ubj\)”}”(hhh]”h¸)”}”(hŒ$Mark drive index 'idx' write-mostly.”h]”hŒ(Mark drive index â€˜idxâ€™ write-mostly.”…””}”(hj¼hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kghj¹ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hj§ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h Kfhj¹ubjF)”}”(hŒ>[max_write_behind ] See '--write-behind=' (man mdadm)”h]”(jL)”}”(hŒ[max_write_behind ]”h]”hŒ[max_write_behind ]”…””}”(hjÚhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h KhhjÖubj\)”}”(hhh]”h¸)”}”(hŒ!See '--write-behind=' (man mdadm)”h]”hŒ%See â€˜--write-behind=â€™ (man mdadm)”…””}”(hjëhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kihjèubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjÖubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h Khhj¹ubjF)”}”(hŒ<[stripe_cache ] Stripe cache size (RAID 4/5/6 only)”h]”(jL)”}”(hŒ[stripe_cache ]”h]”hŒ[stripe_cache ]”…””}”(hj hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h Kjhj ubj\)”}”(hhh]”h¸)”}”(hŒ#Stripe cache size (RAID 4/5/6 only)”h]”hŒ#Stripe cache size (RAID 4/5/6 only)”…””}”(hj hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kkhj ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hj ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h Kjhj¹ubjF)”}”(hŒ´[region_size ] The region_size multiplied by the number of regions is the logical size of the array. The bitmap records the device synchronisation state for each region. ”h]”(jL)”}”(hŒ[region_size ]”h]”hŒ[region_size ]”…””}”(hj8 hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h Kohj4 ubj\)”}”(hhh]”h¸)”}”(hŒ›The region_size multiplied by the number of regions is the logical size of the array. The bitmap records the device synchronisation state for each region.”h]”hŒ›The region_size multiplied by the number of regions is the logical size of the array. The bitmap records the device synchronisation state for each region.”…””}”(hjI hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KmhjF ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hj4 ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h Kohj¹ubjF)”}”(hX“ [raid10_copies <# copies>], [raid10_format ] These two options are used to alter the default layout of a RAID10 configuration. The number of copies is can be specified, but the default is 2. There are also three variations to how the copies are laid down - the default is "near". Near copies are what most people think of with respect to mirroring. If these options are left unspecified, or 'raid10_copies 2' and/or 'raid10_format near' are given, then the layouts for 2, 3 and 4 devices are: ======== ========== ============== 2 drives 3 drives 4 drives ======== ========== ============== A1 A1 A1 A1 A2 A1 A1 A2 A2 A2 A2 A2 A3 A3 A3 A3 A4 A4 A3 A3 A4 A4 A5 A5 A5 A6 A6 A4 A4 A5 A6 A6 A7 A7 A8 A8 .. .. .. .. .. .. .. .. .. ======== ========== ============== The 2-device layout is equivalent 2-way RAID1. The 4-device layout is what a traditional RAID10 would look like. The 3-device layout is what might be called a 'RAID1E - Integrated Adjacent Stripe Mirroring'. If 'raid10_copies 2' and 'raid10_format far', then the layouts for 2, 3 and 4 devices are: ======== ============ =================== 2 drives 3 drives 4 drives ======== ============ =================== A1 A2 A1 A2 A3 A1 A2 A3 A4 A3 A4 A4 A5 A6 A5 A6 A7 A8 A5 A6 A7 A8 A9 A9 A10 A11 A12 .. .. .. .. .. .. .. .. .. A2 A1 A3 A1 A2 A2 A1 A4 A3 A4 A3 A6 A4 A5 A6 A5 A8 A7 A6 A5 A9 A7 A8 A10 A9 A12 A11 .. .. .. .. .. .. .. .. .. ======== ============ =================== If 'raid10_copies 2' and 'raid10_format offset', then the layouts for 2, 3 and 4 devices are: ======== ========== ================ 2 drives 3 drives 4 drives ======== ========== ================ A1 A2 A1 A2 A3 A1 A2 A3 A4 A2 A1 A3 A1 A2 A2 A1 A4 A3 A3 A4 A4 A5 A6 A5 A6 A7 A8 A4 A3 A6 A4 A5 A6 A5 A8 A7 A5 A6 A7 A8 A9 A9 A10 A11 A12 A6 A5 A9 A7 A8 A10 A9 A12 A11 .. .. .. .. .. .. .. .. .. ======== ========== ================ Here we see layouts closely akin to 'RAID1E - Integrated Offset Stripe Mirroring'. ”h]”(jL)”}”(hŒA[raid10_copies <# copies>], [raid10_format ]”h]”hŒA[raid10_copies <# copies>], [raid10_format ]”…””}”(hjg hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h Kªhjc ubj\)”}”(hhh]”(h¸)”}”(hXÃThese two options are used to alter the default layout of a RAID10 configuration. The number of copies is can be specified, but the default is 2. There are also three variations to how the copies are laid down - the default is "near". Near copies are what most people think of with respect to mirroring. If these options are left unspecified, or 'raid10_copies 2' and/or 'raid10_format near' are given, then the layouts for 2, 3 and 4 devices are:”h]”hXÏThese two options are used to alter the default layout of a RAID10 configuration. The number of copies is can be specified, but the default is 2. There are also three variations to how the copies are laid down - the default is â€œnearâ€. Near copies are what most people think of with respect to mirroring. If these options are left unspecified, or â€˜raid10_copies 2â€™ and/or â€˜raid10_format nearâ€™ are given, then the layouts for 2, 3 and 4 devices are:”…””}”(hjx hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Krhju ubj )”}”(hhh]”j)”}”(hhh]”(j)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”Kuh1jhj‰ ubj)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”K uh1jhj‰ ubj)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”Kuh1jhj‰ ubhŒthead”“”)”}”(hhh]”j2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ2 drives”h]”hŒ2 drives”…””}”(hjµ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K|hj² ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj¯ ubj7)”}”(hhh]”h¸)”}”(hŒ3 drives”h]”hŒ3 drives”…””}”(hjÌ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K|hjÉ ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj¯ ubj7)”}”(hhh]”h¸)”}”(hŒ4 drives”h]”hŒ4 drives”…””}”(hjã hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K|hjà ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj¯ ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj¬ ubah}”(h]”h ]”h"]”h$]”h&]”uh1jª hj‰ ubj-)”}”(hhh]”(j2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA1 A1”h]”hŒA1 A1”…””}”(hj hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K~hj ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj ubj7)”}”(hhh]”h¸)”}”(hŒ A1 A1 A2”h]”hŒ A1 A1 A2”…””}”(hj# hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K~hj ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj ubj7)”}”(hhh]”h¸)”}”(hŒA1 A1 A2 A2”h]”hŒA1 A1 A2 A2”…””}”(hj: hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K~hj7 ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA2 A2”h]”hŒA2 A2”…””}”(hjZ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KhjW ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjT ubj7)”}”(hhh]”h¸)”}”(hŒ A2 A3 A3”h]”hŒ A2 A3 A3”…””}”(hjq hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khjn ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjT ubj7)”}”(hhh]”h¸)”}”(hŒA3 A3 A4 A4”h]”hŒA3 A3 A4 A4”…””}”(hjˆ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj… ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjT ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA3 A3”h]”hŒA3 A3”…””}”(hj¨ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K€hj¥ ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj¢ ubj7)”}”(hhh]”h¸)”}”(hŒ A4 A4 A5”h]”hŒ A4 A4 A5”…””}”(hj¿ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K€hj¼ ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj¢ ubj7)”}”(hhh]”h¸)”}”(hŒA5 A5 A6 A6”h]”hŒA5 A5 A6 A6”…””}”(hjÖ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K€hjÓ ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj¢ ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA4 A4”h]”hŒA4 A4”…””}”(hjö hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khjó ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjð ubj7)”}”(hhh]”h¸)”}”(hŒ A5 A6 A6”h]”hŒ A5 A6 A6”…””}”(hj hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjð ubj7)”}”(hhh]”h¸)”}”(hŒA7 A7 A8 A8”h]”hŒA7 A7 A8 A8”…””}”(hj$hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj!ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjð ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj ubj2)”}”(hhh]”(j7)”}”(hhh]”hŒcomment”“”)”}”(hŒ..”h]”hŒ..”…””}”hjFsbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhjAubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj>ubj7)”}”(hhh]”jE)”}”(hŒ.. ..”h]”hŒ.. ..”…””}”hj]sbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhjZubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj>ubj7)”}”(hhh]”jE)”}”(hŒ .. .. ..”h]”hŒ .. .. ..”…””}”hjtsbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhjqubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj>ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j,hj‰ ubeh}”(h]”h ]”h"]”h$]”h&]”Œcols”Kuh1jhj† ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhju ubh¸)”}”(hŒÑThe 2-device layout is equivalent 2-way RAID1. The 4-device layout is what a traditional RAID10 would look like. The 3-device layout is what might be called a 'RAID1E - Integrated Adjacent Stripe Mirroring'.”h]”hŒÕThe 2-device layout is equivalent 2-way RAID1. The 4-device layout is what a traditional RAID10 would look like. The 3-device layout is what might be called a â€˜RAID1E - Integrated Adjacent Stripe Mirroringâ€™.”…””}”(hj¡hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K…hju ubh¸)”}”(hŒZIf 'raid10_copies 2' and 'raid10_format far', then the layouts for 2, 3 and 4 devices are:”h]”hŒbIf â€˜raid10_copies 2â€™ and â€˜raid10_format farâ€™, then the layouts for 2, 3 and 4 devices are:”…””}”(hj¯hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KŠhju ubj )”}”(hhh]”j)”}”(hhh]”(j)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”Kuh1jhjÀubj)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”Kuh1jhjÀubj)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”Kuh1jhjÀubj« )”}”(hhh]”j2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ2 drives”h]”hŒ2 drives”…””}”(hjêhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KŽhjçubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjäubj7)”}”(hhh]”h¸)”}”(hŒ3 drives”h]”hŒ3 drives”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KŽhjþubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjäubj7)”}”(hhh]”h¸)”}”(hŒ4 drives”h]”hŒ4 drives”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KŽhjubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjäubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjáubah}”(h]”h ]”h"]”h$]”h&]”uh1jª hjÀubj-)”}”(hhh]”(j2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA1 A2”h]”hŒA1 A2”…””}”(hjAhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj>ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj;ubj7)”}”(hhh]”h¸)”}”(hŒA1 A2 A3”h]”hŒA1 A2 A3”…””}”(hjXhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KhjUubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj;ubj7)”}”(hhh]”h¸)”}”(hŒA1 A2 A3 A4”h]”hŒA1 A2 A3 A4”…””}”(hjohžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khjlubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj;ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj8ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA3 A4”h]”hŒA3 A4”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K‘hjŒubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj‰ubj7)”}”(hhh]”h¸)”}”(hŒA4 A5 A6”h]”hŒA4 A5 A6”…””}”(hj¦hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K‘hj£ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj‰ubj7)”}”(hhh]”h¸)”}”(hŒA5 A6 A7 A8”h]”hŒA5 A6 A7 A8”…””}”(hj½hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K‘hjºubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj‰ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj8ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA5 A6”h]”hŒA5 A6”…””}”(hjÝhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K’hjÚubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj×ubj7)”}”(hhh]”h¸)”}”(hŒA7 A8 A9”h]”hŒA7 A8 A9”…””}”(hjôhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K’hjñubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj×ubj7)”}”(hhh]”h¸)”}”(hŒA9 A10 A11 A12”h]”hŒA9 A10 A11 A12”…””}”(hj hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K’hj ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj×ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj8ubj2)”}”(hhh]”(j7)”}”(hhh]”jE)”}”(hŒ..”h]”hŒ..”…””}”hj+ sbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhj( ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj% ubj7)”}”(hhh]”jE)”}”(hŒ.. ..”h]”hŒ.. ..”…””}”hjB sbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhj? ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj% ubj7)”}”(hhh]”jE)”}”(hŒ.. .. ..”h]”hŒ.. .. ..”…””}”hjY sbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhjV ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj% ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj8ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA2 A1”h]”hŒA2 A1”…””}”(hjy hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K”hjv ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjs ubj7)”}”(hhh]”h¸)”}”(hŒA3 A1 A2”h]”hŒA3 A1 A2”…””}”(hj hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K”hj ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjs ubj7)”}”(hhh]”h¸)”}”(hŒA2 A1 A4 A3”h]”hŒA2 A1 A4 A3”…””}”(hj§ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K”hj¤ ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjs ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj8ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA4 A3”h]”hŒA4 A3”…””}”(hjÇ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K•hjÄ ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjÁ ubj7)”}”(hhh]”h¸)”}”(hŒA6 A4 A5”h]”hŒA6 A4 A5”…””}”(hjÞ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K•hjÛ ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjÁ ubj7)”}”(hhh]”h¸)”}”(hŒA6 A5 A8 A7”h]”hŒA6 A5 A8 A7”…””}”(hjõ hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K•hjò ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjÁ ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj8ubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA6 A5”h]”hŒA6 A5”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K–hjubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjubj7)”}”(hhh]”h¸)”}”(hŒA9 A7 A8”h]”hŒA9 A7 A8”…””}”(hj,hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K–hj)ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjubj7)”}”(hhh]”h¸)”}”(hŒA10 A9 A12 A11”h]”hŒA10 A9 A12 A11”…””}”(hjChžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K–hj@ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj8ubj2)”}”(hhh]”(j7)”}”(hhh]”jE)”}”(hŒ..”h]”hŒ..”…””}”hjcsbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhj`ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj]ubj7)”}”(hhh]”jE)”}”(hŒ.. ..”h]”hŒ.. ..”…””}”hjzsbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhjwubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj]ubj7)”}”(hhh]”jE)”}”(hŒ.. .. ..”h]”hŒ.. .. ..”…””}”hj‘sbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhjŽubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj]ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hj8ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j,hjÀubeh}”(h]”h ]”h"]”h$]”h&]”Œcols”Kuh1jhj½ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhju ubh¸)”}”(hŒ]If 'raid10_copies 2' and 'raid10_format offset', then the layouts for 2, 3 and 4 devices are:”h]”hŒeIf â€˜raid10_copies 2â€™ and â€˜raid10_format offsetâ€™, then the layouts for 2, 3 and 4 devices are:”…””}”(hj¾hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kšhju ubj )”}”(hhh]”j)”}”(hhh]”(j)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”Kuh1jhjÏubj)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”K uh1jhjÏubj)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”Kuh1jhjÏubj« )”}”(hhh]”j2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ2 drives”h]”hŒ2 drives”…””}”(hjùhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kžhjöubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjóubj7)”}”(hhh]”h¸)”}”(hŒ3 drives”h]”hŒ3 drives”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kžhj ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjóubj7)”}”(hhh]”h¸)”}”(hŒ4 drives”h]”hŒ4 drives”…””}”(hj'hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kžhj$ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjóubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjðubah}”(h]”h ]”h"]”h$]”h&]”uh1jª hjÏubj-)”}”(hhh]”(j2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA1 A2”h]”hŒA1 A2”…””}”(hjPhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K hjMubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjJubj7)”}”(hhh]”h¸)”}”(hŒ A1 A2 A3”h]”hŒ A1 A2 A3”…””}”(hjghžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K hjdubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjJubj7)”}”(hhh]”h¸)”}”(hŒA1 A2 A3 A4”h]”hŒA1 A2 A3 A4”…””}”(hj~hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K hj{ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjJubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjGubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA2 A1”h]”hŒA2 A1”…””}”(hjžhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¡hj›ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj˜ubj7)”}”(hhh]”h¸)”}”(hŒ A3 A1 A2”h]”hŒ A3 A1 A2”…””}”(hjµhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¡hj²ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj˜ubj7)”}”(hhh]”h¸)”}”(hŒA2 A1 A4 A3”h]”hŒA2 A1 A4 A3”…””}”(hjÌhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¡hjÉubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj˜ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjGubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA3 A4”h]”hŒA3 A4”…””}”(hjìhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¢hjéubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjæubj7)”}”(hhh]”h¸)”}”(hŒ A4 A5 A6”h]”hŒ A4 A5 A6”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¢hjubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjæubj7)”}”(hhh]”h¸)”}”(hŒA5 A6 A7 A8”h]”hŒA5 A6 A7 A8”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¢hjubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjæubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjGubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA4 A3”h]”hŒA4 A3”…””}”(hj:hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K£hj7ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj4ubj7)”}”(hhh]”h¸)”}”(hŒ A6 A4 A5”h]”hŒ A6 A4 A5”…””}”(hjQhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K£hjNubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj4ubj7)”}”(hhh]”h¸)”}”(hŒA6 A5 A8 A7”h]”hŒA6 A5 A8 A7”…””}”(hjhhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K£hjeubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj4ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjGubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA5 A6”h]”hŒA5 A6”…””}”(hjˆhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¤hj…ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj‚ubj7)”}”(hhh]”h¸)”}”(hŒ A7 A8 A9”h]”hŒ A7 A8 A9”…””}”(hjŸhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¤hjœubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj‚ubj7)”}”(hhh]”h¸)”}”(hŒA9 A10 A11 A12”h]”hŒA9 A10 A11 A12”…””}”(hj¶hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¤hj³ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj‚ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjGubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒA6 A5”h]”hŒA6 A5”…””}”(hjÖhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¥hjÓubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjÐubj7)”}”(hhh]”h¸)”}”(hŒ A9 A7 A8”h]”hŒ A9 A7 A8”…””}”(hjíhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¥hjêubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjÐubj7)”}”(hhh]”h¸)”}”(hŒA10 A9 A12 A11”h]”hŒA10 A9 A12 A11”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¥hjubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjÐubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjGubj2)”}”(hhh]”(j7)”}”(hhh]”jE)”}”(hŒ..”h]”hŒ..”…””}”hj$sbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhj!ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjubj7)”}”(hhh]”jE)”}”(hŒ.. ..”h]”hŒ.. ..”…””}”hj;sbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhj8ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjubj7)”}”(hhh]”jE)”}”(hŒ .. .. ..”h]”hŒ .. .. ..”…””}”hjRsbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1jDhjOubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjGubeh}”(h]”h ]”h"]”h$]”h&]”uh1j,hjÏubeh}”(h]”h ]”h"]”h$]”h&]”Œcols”Kuh1jhjÌubah}”(h]”h ]”h"]”h$]”h&]”uh1jhju ubh¸)”}”(hŒRHere we see layouts closely akin to 'RAID1E - Integrated Offset Stripe Mirroring'.”h]”hŒVHere we see layouts closely akin to â€˜RAID1E - Integrated Offset Stripe Mirroringâ€™.”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K©hju ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j[hjc ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h Kªhj¹ubjF)”}”(hXø[delta_disks ] The delta_disks option value (-251 < N < +251) triggers device removal (negative value) or device addition (positive value) to any reshape supporting raid levels 4/5/6 and 10. RAID levels 4/5/6 allow for addition of devices (metadata and data device tuple), raid10_near and raid10_offset only allow for device addition. raid10_far does not support any reshaping at all. A minimum of devices have to be kept to enforce resilience, which is 3 devices for raid4/5 and 4 devices for raid6. ”h]”(jL)”}”(hŒ[delta_disks ]”h]”hŒ[delta_disks ]”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h Kµhj™ubj\)”}”(hhh]”h¸)”}”(hXåThe delta_disks option value (-251 < N < +251) triggers device removal (negative value) or device addition (positive value) to any reshape supporting raid levels 4/5/6 and 10. RAID levels 4/5/6 allow for addition of devices (metadata and data device tuple), raid10_near and raid10_offset only allow for device addition. raid10_far does not support any reshaping at all. A minimum of devices have to be kept to enforce resilience, which is 3 devices for raid4/5 and 4 devices for raid6.”h]”hXåThe delta_disks option value (-251 < N < +251) triggers device removal (negative value) or device addition (positive value) to any reshape supporting raid levels 4/5/6 and 10. RAID levels 4/5/6 allow for addition of devices (metadata and data device tuple), raid10_near and raid10_offset only allow for device addition. raid10_far does not support any reshaping at all. A minimum of devices have to be kept to enforce resilience, which is 3 devices for raid4/5 and 4 devices for raid6.”…””}”(hj®hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj«ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hj™ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h Kµhj¹ubjF)”}”(hXÙ[data_offset ] This option value defines the offset into each data device where the data starts. This is used to provide out-of-place reshaping space to avoid writing over data while changing the layout of stripes, hence an interruption/crash may happen at any time without the risk of losing data. E.g. when adding devices to an existing raid set during forward reshaping, the out-of-place space will be allocated at the beginning of each raid device. The kernel raid4/5/6/10 MD personalities supporting such device addition will read the data from the existing first stripes (those with smaller number of stripes) starting at data_offset to fill up a new stripe with the larger number of stripes, calculate the redundancy blocks (CRC/Q-syndrome) and write that new stripe to offset 0. Same will be applied to all N-1 other new stripes. This out-of-place scheme is used to change the RAID type (i.e. the allocation algorithm) as well, e.g. changing from raid5_ls to raid5_n. ”h]”(jL)”}”(hŒ[data_offset ]”h]”hŒ[data_offset ]”…””}”(hjÌhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h KÇhjÈubj\)”}”(hhh]”h¸)”}”(hXÀThis option value defines the offset into each data device where the data starts. This is used to provide out-of-place reshaping space to avoid writing over data while changing the layout of stripes, hence an interruption/crash may happen at any time without the risk of losing data. E.g. when adding devices to an existing raid set during forward reshaping, the out-of-place space will be allocated at the beginning of each raid device. The kernel raid4/5/6/10 MD personalities supporting such device addition will read the data from the existing first stripes (those with smaller number of stripes) starting at data_offset to fill up a new stripe with the larger number of stripes, calculate the redundancy blocks (CRC/Q-syndrome) and write that new stripe to offset 0. Same will be applied to all N-1 other new stripes. This out-of-place scheme is used to change the RAID type (i.e. the allocation algorithm) as well, e.g. changing from raid5_ls to raid5_n.”•Ã¡h]”hXÀThis option value defines the offset into each data device where the data starts. This is used to provide out-of-place reshaping space to avoid writing over data while changing the layout of stripes, hence an interruption/crash may happen at any time without the risk of losing data. E.g. when adding devices to an existing raid set during forward reshaping, the out-of-place space will be allocated at the beginning of each raid device. The kernel raid4/5/6/10 MD personalities supporting such device addition will read the data from the existing first stripes (those with smaller number of stripes) starting at data_offset to fill up a new stripe with the larger number of stripes, calculate the redundancy blocks (CRC/Q-syndrome) and write that new stripe to offset 0. Same will be applied to all N-1 other new stripes. This out-of-place scheme is used to change the RAID type (i.e. the allocation algorithm) as well, e.g. changing from raid5_ls to raid5_n.”…””}”(hjÝhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K¸hjÚubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjÈubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h KÇhj¹ubjF)”}”(hXÁ[journal_dev ] This option adds a journal device to raid4/5/6 raid sets and uses it to close the 'write hole' caused by the non-atomic updates to the component devices which can cause data loss during recovery. The journal device is used as writethrough thus causing writes to be throttled versus non-journaled raid4/5/6 sets. Takeover/reshape is not possible with a raid4/5/6 journal device; it has to be deconfigured before requesting these. ”h]”(jL)”}”(hŒ[journal_dev ]”h]”hŒ[journal_dev ]”…””}”(hjûhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h KÐhj÷ubj\)”}”(hhh]”h¸)”}”(hX¬This option adds a journal device to raid4/5/6 raid sets and uses it to close the 'write hole' caused by the non-atomic updates to the component devices which can cause data loss during recovery. The journal device is used as writethrough thus causing writes to be throttled versus non-journaled raid4/5/6 sets. Takeover/reshape is not possible with a raid4/5/6 journal device; it has to be deconfigured before requesting these.”h]”hX°This option adds a journal device to raid4/5/6 raid sets and uses it to close the â€˜write holeâ€™ caused by the non-atomic updates to the component devices which can cause data loss during recovery. The journal device is used as writethrough thus causing writes to be throttled versus non-journaled raid4/5/6 sets. Takeover/reshape is not possible with a raid4/5/6 journal device; it has to be deconfigured before requesting these.”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KÊhj ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hj÷ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h KÐhj¹ubjF)”}”(hXU[journal_mode ] This option sets the caching mode on journaled raid4/5/6 raid sets (see 'journal_dev ' above) to 'writethrough' or 'writeback'. If 'writeback' is selected the journal device has to be resilient and must not suffer from the 'write hole' problem itself (e.g. use raid1 or raid10) to avoid a single point of failure. ”h]”(jL)”}”(hŒ[journal_mode ]”h]”hŒ[journal_mode ]”…””}”(hj*hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h K×hj&ubj\)”}”(hhh]”h¸)”}”(hX>This option sets the caching mode on journaled raid4/5/6 raid sets (see 'journal_dev ' above) to 'writethrough' or 'writeback'. If 'writeback' is selected the journal device has to be resilient and must not suffer from the 'write hole' problem itself (e.g. use raid1 or raid10) to avoid a single point of failure.”h]”hXRThis option sets the caching mode on journaled raid4/5/6 raid sets (see â€˜journal_dev â€™ above) to â€˜writethroughâ€™ or â€˜writebackâ€™. If â€˜writebackâ€™ is selected the journal device has to be resilient and must not suffer from the â€˜write holeâ€™ problem itself (e.g. use raid1 or raid10) to avoid a single point of failure.”…””}”(hj;hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KÓhj8ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hj&ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h K×hj¹ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j@hj¶ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hj¤ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h K×hjBubeh}”(h]”h ]”h"]”h$]”h&]”uh1j@hj<ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h KPhhÇhžhubjA)”}”(hhh]”jF)”}”(hXì<#raid_devs>: The number of devices composing the array. Each device consists of two entries. The first is the device containing the metadata (if any); the second is the one containing the data. A Maximum of 64 metadata/data device entries are supported up to target version 1.8.0. 1.9.0 supports up to 253 which is enforced by the used MD kernel runtime. If a drive has failed or is missing at creation time, a '-' can be given for both the metadata and data drives for a given position. ”h]”(jL)”}”(hŒ8<#raid_devs>: The number of devices composing the array.”h]”hŒ8<#raid_devs>: The number of devices composing the array.”…””}”(hjzhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h Kâhjvubj\)”}”(hhh]”(h¸)”}”(hX+Each device consists of two entries. The first is the device containing the metadata (if any); the second is the one containing the data. A Maximum of 64 metadata/data device entries are supported up to target version 1.8.0. 1.9.0 supports up to 253 which is enforced by the used MD kernel runtime.”h]”hX+Each device consists of two entries. The first is the device containing the metadata (if any); the second is the one containing the data. A Maximum of 64 metadata/data device entries are supported up to target version 1.8.0. 1.9.0 supports up to 253 which is enforced by the used MD kernel runtime.”…””}”(hj‹hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KÚhjˆubh¸)”}”(hŒ„If a drive has failed or is missing at creation time, a '-' can be given for both the metadata and data drives for a given position.”h]”hŒˆIf a drive has failed or is missing at creation time, a â€˜-â€™ can be given for both the metadata and data drives for a given position.”…””}”(hj™hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kàhjˆubeh}”(h]”h ]”h"]”h$]”h&]”uh1j[hjvubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h Kâhjsubah}”(h]”h ]”h"]”h$]”h&]”uh1j@hhÇhžhhŸh¶h Nubeh}”(h]”Œmapping-table-interface”ah ]”h"]”Œmapping table interface”ah$]”h&]”uh1h¡hh£hžhhŸh¶h Kubh¢)”}”(hhh]”(h§)”}”(hŒExample Tables”h]”hŒExample Tables”…””}”(hjÄhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjÁhžhhŸh¶h Kåubhç)”}”(hX$# RAID4 - 4 data drives, 1 parity (no metadata devices) # No metadata devices specified to hold superblock/bitmap info # Chunk size of 1MiB # (Lines separated for easy reading) 0 1960893648 raid \ raid4 1 2048 \ 5 - 8:17 - 8:33 - 8:49 - 8:65 - 8:81 # RAID4 - 4 data drives, 1 parity (with metadata devices) # Chunk size of 1MiB, force RAID initialization, # min recovery rate at 20 kiB/sec/disk 0 1960893648 raid \ raid4 4 2048 sync min_recovery_rate 20 \ 5 8:17 8:18 8:33 8:34 8:49 8:50 8:65 8:66 8:81 8:82”h]”hX$# RAID4 - 4 data drives, 1 parity (no metadata devices) # No metadata devices specified to hold superblock/bitmap info # Chunk size of 1MiB # (Lines separated for easy reading) 0 1960893648 raid \ raid4 1 2048 \ 5 - 8:17 - 8:33 - 8:49 - 8:65 - 8:81 # RAID4 - 4 data drives, 1 parity (with metadata devices) # Chunk size of 1MiB, force RAID initialization, # min recovery rate at 20 kiB/sec/disk 0 1960893648 raid \ raid4 4 2048 sync min_recovery_rate 20 \ 5 8:17 8:18 8:33 8:34 8:49 8:50 8:65 8:66 8:81 8:82”…””}”hjÒsbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1hæhŸh¶h KéhjÁhžhubeh}”(h]”Œexample-tables”ah ]”h"]”Œexample tables”ah$]”h&]”uh1h¡hh£hžhhŸh¶h Kåubh¢)”}”(hhh]”(h§)”}”(hŒ Status Output”h]”hŒ Status Output”…””}”(hjëhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjèhžhhŸh¶h Küubh¸)”}”(hX?'dmsetup table' displays the table used to construct the mapping. The optional parameters are always printed in the order listed above with "sync" or "nosync" always output ahead of the other arguments, regardless of the order used when originally loading the table. Arguments that can be repeated are ordered by value.”h]”hXKâ€˜dmsetup tableâ€™ displays the table used to construct the mapping. The optional parameters are always printed in the order listed above with â€œsyncâ€ or â€œnosyncâ€ always output ahead of the other arguments, regardless of the order used when originally loading the table. Arguments that can be repeated are ordered by value.”…””}”(hjùhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Kýhjèhžhubh¸)”}”(hŒœ'dmsetup status' yields information on the state and health of the array. The output is as follows (normally a single line, but expanded here for clarity)::”h]”hŒŸâ€˜dmsetup statusâ€™ yields information on the state and health of the array. The output is as follows (normally a single line, but expanded here for clarity):”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhjèhžhubhç)”}”(hŒs1: raid \ 2: <#devices> \ 3: ”h]”hŒs1: raid \ 2: <#devices> \ 3: ”…””}”hjsbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1hæhŸh¶h Mhjèhžhubh¸)”}”(hŒ8Line 1 is the standard output produced by device-mapper.”h]”hŒ8Line 1 is the standard output produced by device-mapper.”…””}”(hj#hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhjèhžhubh¸)”}”(hŒNLine 2 & 3 are produced by the raid target and are best explained by example::”h]”hŒMLine 2 & 3 are produced by the raid target and are best explained by example:”…””}”(hj1hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhjèhžhubhç)”}”(hŒ20 1960893648 raid raid4 5 AAAAA 2/490221568 init 0”h]”hŒ20 1960893648 raid raid4 5 AAAAA 2/490221568 init 0”…””}”hj?sbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1hæhŸh¶h Mhjèhžhubh¸)”}”(hŒÐHere we can see the RAID type is raid4, there are 5 devices - all of which are 'A'live, and the array is 2/490221568 complete with its initial recovery. Here is a fuller description of the individual fields:”h]”hŒÔHere we can see the RAID type is raid4, there are 5 devices - all of which are â€˜Aâ€™live, and the array is 2/490221568 complete with its initial recovery. Here is a fuller description of the individual fields:”…””}”(hjMhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhjèhžhubj)”}”(hX =============== ========================================================= Same as the used to create the array. One char for each device, indicating: - 'A' = alive and in-sync - 'a' = alive but not in-sync - 'D' = dead/failed. The ratio indicating how much of the array has undergone the process described by 'sync_action'. If the 'sync_action' is "check" or "repair", then the process of "resync" or "recover" can be considered complete. One of the following possible states: idle - No synchronization action is being performed. frozen - The current action has been halted. resync - Array is undergoing its initial synchronization or is resynchronizing after an unclean shutdown (possibly aided by a bitmap). recover - A device in the array is being rebuilt or replaced. check - A user-initiated full check of the array is being performed. All blocks are read and checked for consistency. The number of discrepancies found are recorded in . No changes are made to the array by this action. repair - The same as "check", but discrepancies are corrected. reshape - The array is undergoing a reshape. The number of discrepancies found between mirror copies in RAID1/10 or wrong parity values found in RAID4/5/6. This value is valid only after a "check" of the array is performed. A healthy array has a 'mismatch_cnt' of 0. The current data offset to the start of the user data on each component device of a raid set (see the respective raid parameter to support out-of-place reshaping). - 'A' - active write-through journal device. - 'a' - active write-back journal device. - 'D' - dead journal device. - '-' - no journal device. =============== ========================================================= ”h]”j )”}”(hhh]”j)”}”(hhh]”(j)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”Kuh1jhjbubj)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”K9uh1jhjbubj-)”}”(hhh]”(j2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ”h]”hŒ”…””}”(hj‚hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhjubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj|ubj7)”}”(hhh]”h¸)”}”(hŒ1Same as the used to create the array.”h]”hŒ1Same as the used to create the array.”…””}”(hj™hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhj–ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj|ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjyubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ”h]”hŒ”…””}”(hj¹hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhj¶ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj³ubj7)”}”(hhh]”(h¸)”}”(hŒ%One char for each device, indicating:”h]”hŒ%One char for each device, indicating:”…””}”(hjÐhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MhjÍubj)”}”(hhh]”(j)”}”(hŒ'A' = alive and in-sync”h]”h¸)”}”(hjãh]”hŒâ€˜Aâ€™ = alive and in-sync”…””}”(hjåhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhjáubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjÞubj)”}”(hŒ'a' = alive but not in-sync”h]”h¸)”}”(hjúh]”hŒâ€˜aâ€™ = alive but not in-sync”…””}”(hjühžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhjøubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjÞubj)”}”(hŒ'D' = dead/failed.”h]”h¸)”}”(hjh]”hŒâ€˜Dâ€™ = dead/failed.”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhjubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjÞubeh}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h MhjÍubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hj³ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjyubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ”h]”hŒ”…””}”(hj>hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mhj;ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj8ubj7)”}”(hhh]”h¸)”}”(hŒÔThe ratio indicating how much of the array has undergone the process described by 'sync_action'. If the 'sync_action' is "check" or "repair", then the process of "resync" or "recover" can be considered complete.”h]”hŒìThe ratio indicating how much of the array has undergone the process described by â€˜sync_actionâ€™. If the â€˜sync_actionâ€™ is â€œcheckâ€ or â€œrepairâ€, then the process of â€œresyncâ€ or â€œrecoverâ€ can be considered complete.”…””}”(hjUhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MhjRubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj8ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjyubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ ”h]”hŒ ”…””}”(hjuhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M!hjrubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjoubj7)”}”(hhh]”(h¸)”}”(hŒ%One of the following possible states:”h]”hŒ%One of the following possible states:”…””}”(hjŒhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M!hj‰ubjA)”}”(hhh]”(jF)”}”(hŒ4idle - No synchronization action is being performed.”h]”(jL)”}”(hŒidle”h]”hŒidle”…””}”(hj¡hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h M#hjubj\)”}”(hhh]”j)”}”(hhh]”j)”}”(hŒ-No synchronization action is being performed.”h]”h¸)”}”(hj·h]”hŒ-No synchronization action is being performed.”…””}”(hj¹hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M$hjµubah}”(h]”h ]”h"]”h$]”h&]”uh1j hj²ubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h M$hj¯ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h M#hjšubjF)”}”(hŒ,frozen - The current action has been halted.”h]”(jL)”}”(hŒfrozen”h]”hŒfrozen”…””}”(hjâhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h M%hjÞubj\)”}”(hhh]”j)”}”(hhh]”j)”}”(hŒ#The current action has been halted.”h]”h¸)”}”(hjøh]”hŒ#The current action has been halted.”…””}”(hjúhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M&hjöubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjóubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h M&hjðubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjÞubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h M%hjšubjF)”}”(hŒŠresync - Array is undergoing its initial synchronization or is resynchronizing after an unclean shutdown (possibly aided by a bitmap).”h]”(jL)”}”(hŒresync”h]”hŒresync”…””}”(hj#hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h M)hjubj\)”}”(hhh]”j)”}”(hhh]”j)”}”(hŒ}Array is undergoing its initial synchronization or is resynchronizing after an unclean shutdown (possibly aided by a bitmap).”h]”h¸)”}”(hŒ}Array is undergoing its initial synchronization or is resynchronizing after an unclean shutdown (possibly aided by a bitmap).”h]”hŒ}Array is undergoing its initial synchronization or is resynchronizing after an unclean shutdown (possibly aided by a bitmap).”…””}”(hj;hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M(hj7ubah}”(h]”h ]”h"]”h$]”h&]”uh1j hj4ubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h M(hj1ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h M)hjšubjF)”}”(hŒ?recover - A device in the array is being rebuilt or replaced.”h]”(jL)”}”(hŒrecover”h]”hŒrecover”…””}”(hjehžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h M,hjaubj\)”}”(hhh]”j)”}”(hhh]”j)”}”(hŒ3A device in the array is being rebuilt or replaced.”h]”h¸)”}”(hŒ3A device in the array is being rebuilt or replaced.”h]”hŒ3A device in the array is being rebuilt or replaced.”…””}”(hj}hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M,hjyubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjvubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h M,hjsubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjaubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h M,hjšubjF)”}”(hŒõcheck - A user-initiated full check of the array is being performed. All blocks are read and checked for consistency. The number of discrepancies found are recorded in . No changes are made to the array by this action.”h]”(jL)”}”(hŒcheck”h]”hŒcheck”…””}”(hj§hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h M3hj£ubj\)”}”(hhh]”j)”}”(hhh]”j)”}”(hŒãA user-initiated full check of the array is being performed. All blocks are read and checked for consistency. The number of discrepancies found are recorded in . No changes are made to the array by this action.”h]”h¸)”}”(hŒãA user-initiated full check of the array is being performed. All blocks are read and checked for consistency. The number of discrepancies found are recorded in . No changes are made to the array by this action.”h]”hŒãA user-initiated full check of the array is being performed. All blocks are read and checked for consistency. The number of discrepancies found are recorded in . No changes are made to the array by this action.”…””}”(hj¿hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M/hj»ubah}”(h]”h ]”h"]”h$]”h&]”uh1j hj¸ubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h M/hjµubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hj£ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h M3hjšubjF)”}”(hŒ@repair - The same as "check", but discrepancies are corrected.”h]”(jL)”}”(hŒrepair”h]”hŒrepair”…””}”(hjéhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h M6hjåubj\)”}”(hhh]”j)”}”(hhh]”j)”}”(hŒ5The same as "check", but discrepancies are corrected.”h]”h¸)”}”(hŒ5The same as "check", but discrepancies are corrected.”h]”hŒ9The same as â€œcheckâ€, but discrepancies are corrected.”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M6hjýubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjúubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h M6hj÷ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hjåubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h M6hjšubjF)”}”(hŒ,reshape - The array is undergoing a reshape.”h]”(jL)”}”(hŒreshape”h]”hŒreshape”…””}”(hj+hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jKhŸh¶h M8hj'ubj\)”}”(hhh]”j)”}”(hhh]”j)”}”(hŒ"The array is undergoing a reshape.”h]”h¸)”}”(hjAh]”hŒ"The array is undergoing a reshape.”…””}”(hjChžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M9hj?ubah}”(h]”h ]”h"]”h$]”h&]”uh1j hj<ubah}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h M9hj9ubah}”(h]”h ]”h"]”h$]”h&]”uh1j[hj'ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jEhŸh¶h M8hjšubeh}”(h]”h ]”h"]”h$]”h&]”uh1j@hj‰ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j6hjoubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjyubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ”h]”hŒ”…””}”(hj€hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M:hj}ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjzubj7)”}”(hhh]”h¸)”}”(hŒÞThe number of discrepancies found between mirror copies in RAID1/10 or wrong parity values found in RAID4/5/6. This value is valid only after a "check" of the array is performed. A healthy array has a 'mismatch_cnt' of 0.”h]”hŒæThe number of discrepancies found between mirror copies in RAID1/10 or wrong parity values found in RAID4/5/6. This value is valid only after a â€œcheckâ€ of the array is performed. A healthy array has a â€˜mismatch_cntâ€™ of 0.”…””}”(hj—hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M:hj”ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjzubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjyubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ ”h]”hŒ ”…””}”(hj·hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M>hj´ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj±ubj7)”}”(hhh]”h¸)”}”(hŒ£The current data offset to the start of the user data on each component device of a raid set (see the respective raid parameter to support out-of-place reshaping).”h]”hŒ£The current data offset to the start of the user data on each component device of a raid set (see the respective raid parameter to support out-of-place reshaping).”…””}”(hjÎhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h M>hjËubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj±ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjyubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ”h]”hŒ”…””}”(hjîhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MAhjëubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjèubj7)”}”(hhh]”j)”}”(hhh]”(j)”}”(hŒ*'A' - active write-through journal device.”h]”h¸)”}”(hj h]”hŒ.â€˜Aâ€™ - active write-through journal device.”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MAhjubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjubj)”}”(hŒ''a' - active write-back journal device.”h]”h¸)”}”(hj!h]”hŒ+â€˜aâ€™ - active write-back journal device.”…””}”(hj#hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MBhjubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjubj)”}”(hŒ'D' - dead journal device.”h]”h¸)”}”(hj8h]”hŒâ€˜Dâ€™ - dead journal device.”…””}”(hj:hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MChj6ubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjubj)”}”(hŒ'-' - no journal device.”h]”h¸)”}”(hjOh]”hŒâ€˜-â€™ - no journal device.”…””}”(hjQhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MDhjMubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjubeh}”(h]”h ]”h"]”h$]”h&]”j)j*uh1jhŸh¶h MAhjubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjèubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjyubeh}”(h]”h ]”h"]”h$]”h&]”uh1j,hjbubeh}”(h]”h ]”h"]”h$]”h&]”Œcols”Kuh1jhj_ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhj[ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h Mhjèhžhubeh}”(h]”Œ status-output”ah ]”h"]”Œ status output”ah$]”h&]”uh1h¡hh£hžhhŸh¶h Küubh¢)”}”(hhh]”(h§)”}”(hŒMessage Interface”h]”hŒMessage Interface”…””}”(hjšhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hj—hžhhŸh¶h MIubh¸)”}”(hŒ¦The dm-raid target will accept certain actions through the 'message' interface. ('man dmsetup' for more information on the message interface.) These actions include:”h]”hŒ®The dm-raid target will accept certain actions through the â€˜messageâ€™ interface. (â€˜man dmsetupâ€™ for more information on the message interface.) These actions include:”…””}”(hj¨hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MJhj—hžhubj)”}”(hX‚========= ================================================ "idle" Halt the current sync action. "frozen" Freeze the current sync action. "resync" Initiate/continue a resync. "recover" Initiate/continue a recover process. "check" Initiate a check (i.e. a "scrub") of the array. "repair" Initiate a repair of the array. ========= ================================================ ”h]”j )”}”(hhh]”j)”}”(hhh]”(j)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”K uh1jhj½ubj)”}”(hhh]”h}”(h]”h ]”h"]”h$]”h&]”Œcolwidth”K0uh1jhj½ubj-)”}”(hhh]”(j2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ"idle"”h]”hŒ â€œidleâ€”…””}”(hjÝhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MOhjÚubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj×ubj7)”}”(hhh]”h¸)”}”(hŒHalt the current sync action.”h]”hŒHalt the current sync action.”…””}”(hjôhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MOhjñubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj×ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjÔubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ"frozen"”h]”hŒâ€œfrozenâ€”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MPhjubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjubj7)”}”(hhh]”h¸)”}”(hŒFreeze the current sync action.”h]”hŒFreeze the current sync action.”…””}”(hj+hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MPhj(ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjÔubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ"resync"”h]”hŒâ€œresyncâ€”…””}”(hjKhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MQhjHubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjEubj7)”}”(hhh]”h¸)”}”(hŒInitiate/continue a resync.”h]”hŒInitiate/continue a resync.”…””}”(hjbhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MQhj_ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjEubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjÔubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ "recover"”h]”hŒ â€œrecoverâ€”…””}”(hj‚hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MRhjubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj|ubj7)”}”(hhh]”h¸)”}”(hŒ$Initiate/continue a recover process.”h]”hŒ$Initiate/continue a recover process.”…””}”(hj™hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MRhj–ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj|ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjÔubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ"check"”h]”hŒâ€œcheckâ€”…””}”(hj¹hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MShj¶ubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj³ubj7)”}”(hhh]”h¸)”}”(hŒ/Initiate a check (i.e. a "scrub") of the array.”h]”hŒ3Initiate a check (i.e. a â€œscrubâ€) of the array.”…””}”(hjÐhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MShjÍubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hj³ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjÔubj2)”}”(hhh]”(j7)”}”(hhh]”h¸)”}”(hŒ"repair"”h]”hŒâ€œrepairâ€”…””}”(hjðhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MThjíubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjêubj7)”}”(hhh]”h¸)”}”(hŒInitiate a repair of the array.”h]”hŒInitiate a repair of the array.”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MThjubah}”(h]”h ]”h"]”h$]”h&]”uh1j6hjêubeh}”(h]”h ]”h"]”h$]”h&]”uh1j1hjÔubeh}”(h]”h ]”h"]”h$]”h&]”uh1j,hj½ubeh}”(h]”h ]”h"]”h$]”h&]”Œcols”Kuh1jhjºubah}”(h]”h ]”h"]”h$]”h&]”uh1jhj¶ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h MNhj—hžhubeh}”(h]”Œmessage-interface”ah ]”h"]”Œmessage interface”ah$]”h&]”uh1h¡hh£hžhhŸh¶h MIubh¢)”}”(hhh]”(h§)”}”(hŒDiscard Support”h]”hŒDiscard Support”…””}”(hjEhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjBhžhhŸh¶h MYubh¸)”}”(hXªThe implementation of discard support among hardware vendors varies. When a block is discarded, some storage devices will return zeroes when the block is read. These devices set the 'discard_zeroes_data' attribute. Other devices will return random data. Confusingly, some devices that advertise 'discard_zeroes_data' will not reliably return zeroes when discarded blocks are read! Since RAID 4/5/6 uses blocks from a number of devices to calculate parity blocks and (for performance reasons) relies on 'discard_zeroes_data' being reliable, it is important that the devices be consistent. Blocks may be discarded in the middle of a RAID 4/5/6 stripe and if subsequent read results are not consistent, the parity blocks may be calculated differently at any time; making the parity blocks useless for redundancy. It is important to understand how your hardware behaves with discards if you are going to enable discards with RAID 4/5/6.”h]”hX¶The implementation of discard support among hardware vendors varies. When a block is discarded, some storage devices will return zeroes when the block is read. These devices set the â€˜discard_zeroes_dataâ€™ attribute. Other devices will return random data. Confusingly, some devices that advertise â€˜discard_zeroes_dataâ€™ will not reliably return zeroes when discarded blocks are read! Since RAID 4/5/6 uses blocks from a number of devices to calculate parity blocks and (for performance reasons) relies on â€˜discard_zeroes_dataâ€™ being reliable, it is important that the devices be consistent. Blocks may be discarded in the middle of a RAID 4/5/6 stripe and if subsequent read results are not consistent, the parity blocks may be calculated differently at any time; making the parity blocks useless for redundancy. It is important to understand how your hardware behaves with discards if you are going to enable discards with RAID 4/5/6.”…””}”(hjShžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MZhjBhžhubh¸)”}”(hŒëSince the behavior of storage devices is unreliable in this respect, even when reporting 'discard_zeroes_data', by default RAID 4/5/6 discard support is disabled -- this ensures data integrity at the expense of losing some performance.”h]”hŒïSince the behavior of storage devices is unreliable in this respect, even when reporting â€˜discard_zeroes_dataâ€™, by default RAID 4/5/6 discard support is disabled -- this ensures data integrity at the expense of losing some performance.”…””}”(hjahžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MihjBhžhubh¸)”}”(hŒStorage devices that properly support 'discard_zeroes_data' are increasingly whitelisted in the kernel and can thus be trusted.”h]”hŒƒStorage devices that properly support â€˜discard_zeroes_dataâ€™ are increasingly whitelisted in the kernel and can thus be trusted.”…””}”(hjohžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MnhjBhžhubh¸)”}”(hŒwFor trusted devices, the following dm-raid module parameter can be set to safely enable discard support for RAID 4/5/6:”h]”hŒwFor trusted devices, the following dm-raid module parameter can be set to safely enable discard support for RAID 4/5/6:”…””}”(hj}hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h MqhjBhžhubj)”}”(hŒ"'devices_handle_discards_safely' ”h]”h¸)”}”(hŒ 'devices_handle_discards_safely'”h]”hŒ$â€˜devices_handle_discards_safelyâ€™”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Mthj‹ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h MthjBhžhubeh}”(h]”Œdiscard-support”ah ]”h"]”Œdiscard support”ah$]”h&]”uh1h¡hh£hžhhŸh¶h MYubh¢)”}”(hhh]”(h§)”}”(hŒVersion History”h]”hŒVersion History”…””}”(hj®hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hj«hžhhŸh¶h Mxubhç)”}”(hX8 1.0.0 Initial version. Support for RAID 4/5/6 1.1.0 Added support for RAID 1 1.2.0 Handle creation of arrays that contain failed devices. 1.3.0 Added support for RAID 10 1.3.1 Allow device replacement/rebuild for RAID 10 1.3.2 Fix/improve redundancy checking for RAID10 1.4.0 Non-functional change. Removes arg from mapping function. 1.4.1 RAID10 fix redundancy validation checks (commit 55ebbb5). 1.4.2 Add RAID10 "far" and "offset" algorithm support. 1.5.0 Add message interface to allow manipulation of the sync_action. New status (STATUSTYPE_INFO) fields: sync_action and mismatch_cnt. 1.5.1 Add ability to restore transiently failed devices on resume. 1.5.2 'mismatch_cnt' is zero unless [last_]sync_action is "check". 1.6.0 Add discard support (and devices_handle_discard_safely module param). 1.7.0 Add support for MD RAID0 mappings. 1.8.0 Explicitly check for compatible flags in the superblock metadata and reject to start the raid set if any are set by a newer target version, thus avoiding data corruption on a raid set with a reshape in progress. 1.9.0 Add support for RAID level takeover/reshape/region size and set size reduction. 1.9.1 Fix activation of existing RAID 4/10 mapped devices 1.9.2 Don't emit '- -' on the status table line in case the constructor fails reading a superblock. Correctly emit 'maj:min1 maj:min2' and 'D' on the status line. If '- -' is passed into the constructor, emit '- -' on the table line and '-' as the status line health character. 1.10.0 Add support for raid4/5/6 journal device 1.10.1 Fix data corruption on reshape request 1.11.0 Fix table line argument order (wrong raid10_copies/raid10_format sequence) 1.11.1 Add raid4/5/6 journal write-back support via journal_mode option 1.12.1 Fix for MD deadlock between mddev_suspend() and md_write_start() available 1.13.0 Fix dev_health status at end of "recover" (was 'a', now 'A') 1.13.1 Fix deadlock caused by early md_stop_writes(). Also fix size an state races. 1.13.2 Fix raid redundancy validation and avoid keeping raid set frozen 1.14.0 Fix reshape race on small devices. Fix stripe adding reshape deadlock/potential data corruption. Update superblock when specific devices are requested via rebuild. Fix RAID leg rebuild errors. 1.15.0 Fix size extensions not being synchronized in case of new MD bitmap pages allocated; also fix those not occurring after previous reductions 1.15.1 Fix argument count and arguments for rebuild/write_mostly/journal_(dev|mode) on the status line.”h]”hX8 1.0.0 Initial version. Support for RAID 4/5/6 1.1.0 Added support for RAID 1 1.2.0 Handle creation of arrays that contain failed devices. 1.3.0 Added support for RAID 10 1.3.1 Allow device replacement/rebuild for RAID 10 1.3.2 Fix/improve redundancy checking for RAID10 1.4.0 Non-functional change. Removes arg from mapping function. 1.4.1 RAID10 fix redundancy validation checks (commit 55ebbb5). 1.4.2 Add RAID10 "far" and "offset" algorithm support. 1.5.0 Add message interface to allow manipulation of the sync_action. New status (STATUSTYPE_INFO) fields: sync_action and mismatch_cnt. 1.5.1 Add ability to restore transiently failed devices on resume. 1.5.2 'mismatch_cnt' is zero unless [last_]sync_action is "check". 1.6.0 Add discard support (and devices_handle_discard_safely module param). 1.7.0 Add support for MD RAID0 mappings. 1.8.0 Explicitly check for compatible flags in the superblock metadata and reject to start the raid set if any are set by a newer target version, thus avoiding data corruption on a raid set with a reshape in progress. 1.9.0 Add support for RAID level takeover/reshape/region size and set size reduction. 1.9.1 Fix activation of existing RAID 4/10 mapped devices 1.9.2 Don't emit '- -' on the status table line in case the constructor fails reading a superblock. Correctly emit 'maj:min1 maj:min2' and 'D' on the status line. If '- -' is passed into the constructor, emit '- -' on the table line and '-' as the status line health character. 1.10.0 Add support for raid4/5/6 journal device 1.10.1 Fix data corruption on reshape request 1.11.0 Fix table line argument order (wrong raid10_copies/raid10_format sequence) 1.11.1 Add raid4/5/6 journal write-back support via journal_mode option 1.12.1 Fix for MD deadlock between mddev_suspend() and md_write_start() available 1.13.0 Fix dev_health status at end of "recover" (was 'a', now 'A') 1.13.1 Fix deadlock caused by early md_stop_writes(). Also fix size an state races. 1.13.2 Fix raid redundancy validation and avoid keeping raid set frozen 1.14.0 Fix reshape race on small devices. Fix stripe adding reshape deadlock/potential data corruption. Update superblock when specific devices are requested via rebuild. Fix RAID leg rebuild errors. 1.15.0 Fix size extensions not being synchronized in case of new MD bitmap pages allocated; also fix those not occurring after previous reductions 1.15.1 Fix argument count and arguments for rebuild/write_mostly/journal_(dev|mode) on the status line.”…””}”hj¼sbah}”(h]”h ]”h"]”h$]”h&]”höh÷uh1hæhŸh¶h M|hj«hžhubeh}”(h]”Œversion-history”ah ]”h"]”Œversion history”ah$]”h&]”uh1h¡hh£hžhhŸh¶h Mxubeh}”(h]”Œdm-raid”ah ]”h"]”Œdm-raid”ah$]”h&]”uh1h¡hhhžhhŸh¶h Kubeh}”(h]”h ]”h"]”h$]”h&]”Œsource”h¶uh1hŒcurrent_source”NŒcurrent_line”NŒsettings”Œdocutils.frontend”ŒValues”“”)”}”(h¦NŒ generator”NŒ datestamp”NŒsource_link”NŒ source_url”NŒ toc_backlinks”j6Œfootnote_backlinks”KŒ sectnum_xform”KŒstrip_comments”NŒstrip_elements_with_classes”NŒ strip_classes”NŒreport_level”KŒ halt_level”KŒexit_status_level”KŒdebug”NŒwarning_stream”NŒ traceback”ˆŒinput_encoding”Œ utf-8-sig”Œinput_encoding_error_handler”Œstrict”Œoutput_encoding”Œutf-8”Œoutput_encoding_error_handler”jüŒerror_encoding”Œutf-8”Œerror_encoding_error_handler”Œbackslashreplace”Œ language_code”Œen”Œrecord_dependencies”NŒconfig”NŒ id_prefix”hŒauto_id_prefix”Œid”Œ dump_settings”NŒdump_internals”NŒdump_transforms”NŒdump_pseudo_xml”NŒexpose_internals”NŒstrict_visitor”NŒ_disable_config”NŒ_source”h¶Œ_destination”NŒ _config_files”]”Œ7/var/lib/git/docbuild/linux/Documentation/docutils.conf”aŒfile_insertion_enabled”ˆŒraw_enabled”KŒline_length_limit”M'Œpep_references”NŒpep_base_url”Œhttps://peps.python.org/”Œpep_file_url_template”Œpep-%04d”Œrfc_references”NŒrfc_base_url”Œ&https://datatracker.ietf.org/doc/html/”Œ tab_width”KŒtrim_footnote_reference_space”‰Œsyntax_highlight”Œlong”Œsmart_quotes”ˆŒsmartquotes_locales”]”Œcharacter_level_inline_markup”‰Œdoctitle_xform”‰Œ docinfo_xform”KŒsectsubtitle_xform”‰Œ image_loading”Œlink”Œembed_stylesheet”‰Œcloak_email_addresses”ˆŒsection_self_link”‰Œenv”NubŒreporter”NŒindirect_targets”]”Œsubstitution_defs”}”Œsubstitution_names”}”Œrefnames”}”Œrefids”}”Œnameids”}”(j×jÔj¾j»jåjâj”j‘j?j<j¨j¥jÏjÌuŒ nametypes”}”(j×‰j¾‰jå‰j”‰j?‰j¨‰jÏ‰uh}”(jÔh£j»hÇjâjÁj‘jèj<j—j¥jBjÌj«uŒ footnote_refs”}”Œ citation_refs”}”Œ autofootnotes”]”Œautofootnote_refs”]”Œsymbol_footnotes”]”Œsymbol_footnote_refs”]”Œ footnotes”]”Œ citations”]”Œautofootnote_start”KŒsymbol_footnote_start”KŒ id_counter”Œcollections”ŒCounter”“”}”…”R”Œparse_messages”]”Œtransform_messages”]”Œtransformer”NŒinclude_log”]”Œ decoration”Nhžhub.