mmfsadm command
The mmfsadm command is intended for use by trained service personnel. IBM® suggests you do not run this command except under the direction of such personnel.
Note: The contents of the mmfsadm command output might vary from release to
release, which could obsolete any user programs that depend on that output. Therefore, we suggest
that you do not create user programs that invoke the mmfsadm command.
The mmfsadm command extracts data from GPFS without using locking, so that it can collect the data in the event of
locking errors. In certain rare cases, this can cause GPFS or the node to fail. Several options of this command exist and might be
required for use:
- cleanup
- Delete shared segments left by a previously failed GPFS daemon without actually restarting the daemon.
- dump what
- Dumps the state of a large number of internal state values that might be useful in determining the sequence of events. The what parameter can be set to all, indicating that all available data should be collected, or to another value, indicating more restricted collection of data. The output is presented to STDOUT and should be collected by redirecting STDOUT. For more information about internal GPFS™ states, see the mmdiag command.
- showtrace
- Shows the current level for each subclass of tracing available in GPFS. Trace level 14 provides the highest level of tracing for the class and trace level 0 provides no tracing. Intermediate values exist for most classes. More tracing requires more storage and results in a higher probability of overlaying the required event.
- trace class n
- Sets the trace class to the value specified by n. Actual trace gathering only occurs when the mmtracectl command has been issued.
Other options provide interactive GPFS debugging, but are not described here. Output from the mmfsadm command is required in almost all cases where a GPFS problem is being reported. The mmfsadm command collects data only on the node where it is issued. Depending on the nature of the problem, the mmfsadm command output might be required from several or all nodes. The mmfsadm command output from the file system manager is often required.
To determine where the file system manager is, issue the mmlsmgr
command:
mmlsmgr
Output similar to this example is displayed:
file system manager node
---------------- ------------------
fs3 9.114.94.65 (c154n01)
fs2 9.114.94.73 (c154n09)
fs1 9.114.94.81 (c155n01)
Cluster manager node: 9.114.94.65 (c154n01)