{"id":3357,"date":"2022-12-20T17:02:26","date_gmt":"2022-12-20T20:02:26","guid":{"rendered":"http:\/\/lode.uno\/linux-man\/index.php\/2022\/12\/20\/btrfsselectsuper-man8\/"},"modified":"2022-12-20T17:02:26","modified_gmt":"2022-12-20T20:02:26","slug":"btrfsselectsuper-man8","status":"publish","type":"post","link":"https:\/\/lode.uno\/linux-man\/2022\/12\/20\/btrfsselectsuper-man8\/","title":{"rendered":"BTRFS−SELECT−SUPER (man8)"},"content":{"rendered":"

BTRFS\u2212SELECT\u2212SUPER<\/h1>\n

NAME<\/a>
SYNOPSIS<\/a>
DESCRIPTION<\/a>
OPTIONS<\/a>
SEE ALSO<\/a> <\/p>\n

\n

NAME <\/a> <\/h2>\n

btrfs-select-super \u2212 overwrite primary superblock with a backup copy<\/p>\n

SYNOPSIS <\/a> <\/h2>\n

btrfs\u2212select\u2212super<\/b> \u2212s number <\/i><\/p>\n

DESCRIPTION <\/a> <\/h2>\n

Destructively overwrite all copies of the superblock with a specified copy. This helps in certain cases, for example when write barriers were disabled during a power failure and not all superblocks were written, or if the primary superblock is damaged, eg. accidentally overwritten.<\/p>\n

The filesystem specified by device<\/i> must not be mounted.<\/p>\n

Note<\/big>
Prior to overwriting the primary superblock, please make sure that the backup copies are valid!<\/b><\/p>\n

To dump a superblock use the btrfs inspect\u2212internal dump\u2212super<\/b> command.<\/p>\n

Then run the check (in the non\u2212repair mode) using the command btrfs check \u2212s<\/b> where \u2212s<\/i> specifies the superblock copy to use.<\/p>\n

Superblock copies exist in the following offsets on the device:<\/p>\n

\u2022 primary: 64KiB<\/i> (65536)<\/p>\n

\u2022 1st copy: 64MiB<\/i> (67108864)<\/p>\n

\u2022 2nd copy: 256GiB<\/i> (274877906944)<\/p>\n

A superblock size is 4KiB<\/i> (4096).<\/p>\n

OPTIONS <\/a> <\/h2>\n

\u2212s|\u2212\u2212super <\/i><\/big><\/p>\n

use ‘superblock\u2019th superblock copy, valid values are 0 1 or 2 if the respective superblock offset is within the device size<\/big><\/p>\n

SEE ALSO <\/a> <\/h2>\n

btrfs\u2212inspect\u2212internal<\/b>(8), btrfsck check<\/b>(8)<\/big><\/p>\n

\n","protected":false},"excerpt":{"rendered":"

btrfs-select-super \u2212 overwrite primary superblock with a backup copy <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[5,52,485,4],"class_list":["post-3357","post","type-post","status-publish","format-standard","hentry","category-8-administracion-del-sistema","tag-5","tag-administracion","tag-btrfs-select-super","tag-man8"],"gutentor_comment":0,"_links":{"self":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/posts\/3357","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/comments?post=3357"}],"version-history":[{"count":0,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/posts\/3357\/revisions"}],"wp:attachment":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/media?parent=3357"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/categories?post=3357"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/tags?post=3357"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}