Serviceguard NFS Toolkit A.11.31.02, A.11.11.06, and A.11.23.05 Administrator's Guide

NOTE: If you enable the File Lock Migration feature, an NFS client (or group of
clients) may hit a corner case of requesting a file lock on the HA/NFS server and
not receiving a crash recovery notification message when the HA/NFS package
migrates to an adoptive node. This occurs only when the NFS client sends its initial
lock request to the HA/NFS server and then the HA/NFS package moves to an
adoptive node before the FLM script copies the /var/statmon/sm entry for this
client to the package holding directory.
The probability of hitting this corner-case problem is not very high, because the
SM file copy interval is very short (by default, five seconds). The chances of an
NFS client (or group of NFS clients) sending its initial lock request (it must be the
initial request, since this request generates the /var/statmon/sm file) to the
HA/NFS server and having the package migrate within this same five seconds
window are extremely unlikely.
If you repeatedly experience a problem with this corner-case scenario, reduce the
copy time interval by setting the PROPAGATE_INTERVAL parameter to a lower
value.
Editing the NFS Monitor Script (nfs.mon)
The NFS monitor script, nfs.mon, contains NFS-specific monitor variables and
functions. The nfs.mon script is an optional component of HA/NFS. The hanfs.sh
file specifies whether the NFS monitor script is used. The following steps describe how
to configure the NFS monitor script:
1. To monitor the File Lock Migration script (nfs.flm), set the
NFS_FILE_LOCK_MIGRATION variable to 1, and set the NFS_FLM_SCRIPT name
to match the hanfs.sh script value for this variable:
NFS_FILE_LOCK_MIGRATION=1 NFS_FLM_SCRIPT="${0%/*}nfs1.flm"
Configuring a Serviceguard NFS Package 35