Lustre 1.6 Operations Manual

Note – If your system is upgraded from 1.4.x to 1.6.x, you can mount the Lustre
client on both Lustre versions. If the file system was originallycreated using Lustre
1.6.x, then you will not be able to mount the fildsystem created using an earlier
Lustre version.
13.2.3 Starting Clients
You can start a new client with an old MDT by using the old format of the client
mount command:
client# mount -t lustre ://client
You can start a new client with an upgraded MDT by using the new format and
pointing it at the MGS, not the MDT (for co-located MDT/MGS, this is the same):
client# mount -t lustre :/
Old clients always use the old format of the mount command, regardless of whether
the MDT has been upgraded or not.
13.2.4 Upgrading a Single File system
tunefs.lustre will find the old client log on an 1.4.x MDT that is being upgraded
to 1.6. (If the name of the client log is not "client", use the lustre_up14.sh script,
described in Step 2 and Step 3.)
1. Shut down the MDT.
mdt1# lconf --failover --cleanup config.xml
2. Install the new Lustre version and run tunefs.lustre to upgrade the
configuration.
There are two options:
■ Rolling upgrade keeps a copy of the original configuration log, allowing
immediate reintegration into a live file system, but prevents OSC parameter
and failover NID changes. (The writeconf procedure can be performed later to
eliminate these restrictions. For details, see Running the Writeconf Command.)
■
mdt1# tunefs.lustre --mgs --mdt --fsname=testfs /dev/sda1
i.--writeconf begins a new configuration log, allowing permanent modification
of all parameters (see Changing Parameters), but requiring all other servers
and clients to be stopped at this point. No clients can be started until all OSTs
are upgraded.
13-4 Lustre 1.6 Operations Manual • September 2008