Veritas Volume Manager 4.1 Administrator's Guide (HP-UX 11i v3, February 2007)

Administering DMP Using vxdmpadm
128 VERITAS Volume Manager Administrator’s Guide
Starting the DMP Restore Daemon
The DMP restore daemon re-examines the condition of paths at a specified interval. The
type of analysis it performs on the paths depends on the specified checking policy.
Note The DMP restore daemon does not change the disabled state of the path through a
controller that you have disabled using vxdmpadm disable.
Use the start restore command to start the restore daemon and specify one of the
following policies:
◆ check_all
The restore daemon analyzes all paths in the system and revives the paths that are
back online, as well as disabling the paths that are inaccessible. The command to start
the restore daemon with this policy is:
# vxdmpadm start restore policy=check_all [interval=seconds]
◆ check_alternate
The restore daemon checks that at least one alternate path is healthy. It generates a
notification if this condition is not met. This policy avoids inquiry commands on all
healthy paths, and is less costly than check_all in cases where a large number of
paths are available. This policy is the same as check_all if there are only two paths
per DMP node. The command to start the restore daemon with this policy is:
# vxdmpadm start restore policy=check_alternate [interval=seconds]
◆ check_disabled
This is the default policy. The restore daemon checks the condition of paths that were
previously disabled due to hardware failures, and revives them if they are back
online. The command to start the restore daemon with this policy is:
# vxdmpadm start restore policy=check_disabled [interval=seconds]
◆ check_periodic
The restore daemon performs check_all once in a given number of cycles, and
check_disabled in the remainder of the cycles. This policy may lead to periodic
slowing down (due to check_all) if there are a large number of paths available. The
command to start the restore daemon with this policy is:
# vxdmpadm start restore policy=check_periodic interval=seconds \
[period=number]
The interval attribute must be specified for this policy. The default number of
cycles between running the check_all policy is 10.