nfsstat [ interval ]
nfsstat [ -c ] [ -t ] -h [ ip_address | host_name ]
nfsstat -l [ -t ]
nfsstat -z
If the interval argument is specified, nfsstat continuously displays the summary information for the following NFS requests: getattr, lookup, readlink, read, write, create, remove, and readdir/readdirplus. The first line of data displayed, and every 20th line thereafter, contains cumulative statistics. Each subsequent line shows incremental statistics for the interval (in seconds) since the last display.
Per-client statistics can also be collected and displayed by enabling the nfs.per_client_stats.enable options (using the options command - see na_options(1)) and invoking nfsstat with the -h or the -l options. Perclient statistics are collected for up to the first 256 NFS clients that have mounted the filesystem on the given filer.
-h Displays per-client statistics since last zeroed with the -z option (or since reboot if statistics have not been zeroed). The statistics are displayed on a per-client basis, with the IP address and host name (where available) of each client being displayed at the head of each client's block of statistics.
If an optional IP address or host name is specified with the -h option, only the statistics associated with this client are displayed.
-l Displays a list of the clients whose statistics have been collected on a per-client basis, along with the total NFS calls for that client since last reboot, or last zeroed with the -z option, the count being displayed both as the actual count and as a percentage of calls from all clients.
-z Zeroes (reinitializes) the current statistics. (However, statistics since boot are also retained.)
-c Includes reply cache statistics in the data displayed.
-t Displays the statistics since boot time, rather than since the last time they were zeroed.
The server RPC display includes the following fields, with separate values for TCP and UDP:
nullrecv The number of times an RPC call was not available when it was thought to be received.
nfsstat -l reports unexpected percentages, if the nfs.per_client_stats.enable option is enabled after the system has been running for a while (typically this option should be enabled at system startup time via the /etc/rc file). Resetting the statistics via the nfsstat -z command will clear this condition.
nfsstat -h and nfsstat -l list some clients that have made no NFS calls to the filer. Also, nfsstat -z clears the statistics, but does not clear the list of clients (for the per-client statistics). The same clients will continue to be listed with the nfsstat -h or the nfsstat -l options even though they may have made no NFS calls after the statistics were cleared.
The -h and -l options display the combined client information for both the takeover filer and the failed filer.
The NFS statistics are cumulative. That is, a giveback operation does not zero out the NFS statistics. After giving back the failed filer's resources, the takeover filer does not subtract the statistics about NFS operations it performed on behalf of the failed filer when it was in takeover mode.