From 56db46d9a5fbb4dc2726b5723754a4afe7b5419d Mon Sep 17 00:00:00 2001 From: Arshad Hussain Date: Fri, 19 Mar 2021 14:57:36 +0530 Subject: [PATCH] LUDOC-373 manual: Add section on Lustre xattrs This patch adds a section on lustre attrs Signed-off-by: Arshad Hussain Change-Id: I29c888390490701b1bafbfc078a2d3ddcf3cb42c Reviewed-on: https://review.whamcloud.com/42108 Tested-by: jenkins Reviewed-by: Andreas Dilger --- UnderstandingLustre.xml | 39 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 38 insertions(+), 1 deletion(-) diff --git a/UnderstandingLustre.xml b/UnderstandingLustre.xml index 7769017..5bace3b 100644 --- a/UnderstandingLustre.xml +++ b/UnderstandingLustre.xml @@ -875,9 +875,46 @@ to utilize the full file system bandwidth. For more information about striping, see . + + Extended Attributes(xattrs) + Lustre uses lov_user_md_v1/lov_user_md_v3 data-structures to + maintain its file striping information under xattrs. Extended + attributes are created when files and directory are created. Lustre + uses trusted extended attributes to store its + parameters which are root-only accessible. The parameters are: + + + + trusted.lov: + Holds layout for a regular file, or default file layout stored + on a directory (also accessible as lustre.lov + for non-root users). + + + + + trusted.lma: + Holds FID and extra state flags for current file + + + + trusted.lmv: + Holds layout for a striped directory (DNE 2), not present otherwise + + + + + trusted.link: + Holds parent directory FID + filename for each link to a file + (for lfs fid2path) + + + xattr which are stored and present in the file could be verify + using: + # getfattr -d -m - /mnt/testfs/file> -- 1.8.3.1