Managing Serviceguard NFS for Linux, March 2009

• Execute any external script specified. In NFS lock_migration.sh is executed if lock
migration is enabled in the package configuration file.
• The NFS script initiates the NFS monitor script to check periodically on the health of NFS
services, if you have configured your NFS package to use the monitor script.
NOTE: After completing the above sequence, the NFS server is active, and clients can
NFS-mount the exported file systems associated with the package.
Starting File Lock Migration
If you enable LOCK MIGRATION in the package configuration file. The script
lock_migration.sh present in usr/local/cmcluster/conf/scripts/tkit/nfs
directory in Red Hat and /opt/cmcluster/conf/scripts/tkit/nfs directory in SLES is
invoked. This script is executed as an external script.
The lock_migration.sh will in turn call the NFS control script with the lock_migration
parameter. The following is performed by the control script:
• Populates the /var/lib/nfs/sm directory on SLES and /var/lib/nfs/statd/sm
directory on Red Hat with the Status Monitor entries from the configured holding directory
of the package, and subsequently removes the entries from the holding directory.
• Kills any running copy of the NFS File Lock Migration synchronization script, nfs.flm.
• Restarts the lockd and sm-notify on SLES and rpc.statd on Red Hat using the package
IP. Restarting this daemon triggers a crash recovery notification event, whereby sm-notify/
rpc.statd sends crash notification messages to all clients listed in the /var/lib/nfs/
statd/sm directory on Red Hat and /var/lib/nfs/sm directory on SLES.
• Starts the File Lock Migration synchronization script, which periodically copies the SM
directory entries to the holding directory.
Halting the NFS Services
When called with the stop parameter, the control script does the following:
• Removes the package IP address from the LAN card on the current node.
• The package control script invokes the tkit_module.sh to run the NFS script and to halt
the NFS related process.
• The NFS script un-exports all file systems associated with the package so that they can no
longer be NFS-mounted by clients.
• The NFS script halts the monitor process.
• The NFS script halts the File Lock Migration synchronization script if you enable the File
Lock Migration feature. The NFS daemons are also halted to unmount the filesystem.
• Unmounts each file system associated with the package.
• Deactivates each volume group associated with the package.
NOTE: After completing the above sequence, the NFS package is inactive on the current
node and may start up on an alternate node or be restarted later on the same node.
How the Monitor Script works
The monitor script nfs.mon, located in the directory/usr/local/cmcluster/nfstoolkit
for Red Hat environments, and /opt/cmcluster/nfstoolkit for SLES environments), works
by periodically checking the status of NFS services using the rpcinfo command. If any service
fails to respond, the script exits, causing a switch to an adoptive node.
16 Serviceguard NFS for LINUX Introduction