[LUDOC-514] tar --acls option for proper POSIX ACLs backup/restore of MDTs

• Status: Resolved
• Project: Lustre Documentation
• Type: Improvement
• Priority: Major
• Reporter: Stephane Thiell
• Assignee: Lustre Manual Triage
• Resolution: Fixed
• Severity: 3

Description

Tar does only restore the following xattr if --acls is provided:

system.posix_acl_access
system.posix_acl_default

See: https://git.savannah.gnu.org/cgit/tar.git/tree/src/xattrs.c#n283

The documentation should be updated to mention --acls for MDT backup/restore, otherwise all POSIX ACLs are lost. I will submit a doc patch shortly.

Alternatively, one can use getfacl/setfacl to backup/restore ACLs.

Lastly, using -P / --absolute-names speeds up tremendously the extraction for trusted archive with hardlinks (like MDT backup archives).
See:

• https://mort.coffee/home/tar/
• https://www.gnu.org/software/tar/manual/html_node/absolute.html

 

Comments

[Gerrit Updater]

"Stephane Thiell <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/c/doc/manual/+/51599
Subject: LUDOC-514: add --acls and -P for MDT backup/restore
Project: doc/manual
Branch: master
Current Patch Set: 1
Commit: 610458bc82d5a51308e906d82527863e242c76f4

[Gerrit Updater]

"Andreas Dilger <[e-mail]>" merged in patch https://review.whamcloud.com/c/doc/manual/+/51599/
Subject: LUDOC-514: add --acls and -P for MDT backup/restore
Project: doc/manual
Branch: master
Current Patch Set:
Commit: da6e9fdcc2fcacc234ba9b472124d4d2a89d855a