The pnfsdskill(8) command will normally fail if there is no valid mirror
for the DS to be disabled. However, a system administrator may need to
disable a DS which does not have a valid mirror so that the nfsd threads
can be terminated. This patch adds a "-f" option to pnfsdskill(8) that
uses the kernel changes made by r336141 to implement this "forced" case
of disabling a DS.
This patch only affects the pNFS server.
This command can be used by a sysadmin to disable a malfunctioning pNFS server
mirrored DS. It is safe to use when a mirrored DS has already been disabled
via an I/O or network partitioning error.
