Lustre 1.6 Operations Manual

The following computation is used to determine which offsets in the file are affected:
[(C*N + X)*S, (C*N + X)*S + S - 1], N = { 0, 1, 2, ...}
where:
C = stripe count
S = stripe size
X = index of bad ost for this file
Example: for a file with 2 stripes, stripe size = 1M, bad OST is index 0 you would
have holes in your file at:
[(2*N + 0)*1M, (2*N + 0)*1M + 1M - 1], N = { 0, 1, 2, ...}
If the filesystem can't be mounted, there isn't anything currently that would parse
metadata directly from an MDS. If the bad OST is definitely not starting, options for
mounting the filesystem anyway are to provide a loop device OST in its place, or to
replace it with a newly formatted OST. In that case the missing objects are created
and will read as zero-filled.
How-To: New Lustre network configuration
Updating Lustre's network configuration during an upgrade to version 1.4.6.
Outline necessary changes to Lustre configuration for the new networking features
in v. 1.4.6. Further details may be found in the Lustre manual excerpts found at:
https://wiki.clusterfs.com/cfs/intra/FrontPage?action=AttachFile&do=get&target=
LustreManual.pdf
Backwards Compatibility
The 1.4.6 version of Lustre itself uses the same wire protocols as the previous release,
but has a different network addressing scheme and a much simpler configuration for
routing.
In single-network configurations, LNET can be configured to work with the 1.4.5
networking (portals) so that rolling upgrades can be performed on a cluster. See the
'portals_compatibility' parameter below.
When 'portals_compatibility' is enabled, old XML configuration files remain
compatible. lconf automatically converts old-style network addresses to the new
LNET style.
If a rolling upgrade is not required (that is, all clients and servers can be stopped at
one time), then follow the standard procedure:
D-22 Lustre 1.6 Operations Manual • September 2008