Continentalclusters Version A.06.01 Release Notes, September 2007 (T2346-90009)

Continentalclusters Version A.06.01 Release Notes
Known Problems and Workarounds
Chapter 1 19
The default behavior of LVM is to retry access forever following a
failure. There are a number of ways to recover from this application
hang problem:
— Reboot the node. The package will then move to another node in
the cluster.
— Fix the problem so that one or more PV Links is restored. The
application will then continue normally.
— It is also possible to change the default LVM behavior so that it
will not retry forever. There is an lvchange option that will
establish a timeout value which will cause LVM to return an
error to the application if the access to the array has failed and
the timeout period has expired. The command uses the following
format:
lvchange -t <seconds> /dev/<vgname>/<lvname>
This command must be run from one host, on all logical volumes
in the package volume groups. A starting timeout value of 60
seconds is suggested; the timeout must not be set to less than 60
seconds.
Once the lvchange -t command is run on a host, all other hosts
will automatically inherit the new timeout value for the logical
volumes. View the current timeout value by running the lvdisplay
command and checking the value listed for “IO Timeout
(Seconds)”. If the value is displayed as “default,” then LVM will
use the default behavior and retry forever.