File system monitoring with fsmond (file system monitor daemon)

During boot up of the POSIX subsystem, the file system monitor daemon fsmond is automatically started via rc scripts and automatically ended at the shut down of the POSIX subsystem (see below). It monitors the critical file systems / (root) and /var.

The allocation percentage of these files systems is checked regularly every interval seconds by the daemon. If the threshold warnlimit value is exceeded, the warning POS4030 will be output on the console. If the threshold errorlimit value is exceeded, the acknowledge message POS4031 will be output to the console.

Syntax

fsmond[ -t interval][ -w warnlimit][ -e errorlimit]

-t interval

This option is used to set the length of the file system test period in seconds. The permitted value is between 1 and 3600. Default value is 120.

-w warnlimit

This option indicates the file system allocation percentage at which the warning message is to be output to the console. A warning message is output to the console if this value worsens during the next run of fsmond. The permitted value is between 1 and 99. Default value is 80.

-e errorlimit

This option indicates the file system allocation percentage at which an acknowledge message is output to the console. The permitted value is between 1 and 99. Default value is 90.

The value of errorlimit must exceed the value of warnlimit by at least 5.

Note

Allocation percentage

The allocation percentage for warnlimit and errorlimit (given in percentages) corresponds to the filling degree as output by the command call df -v (ratio of available to allocated blocks for privileged users).

rc scripts

The rc scripts for the automatic start/end of the daemon are as follows:
/etc/rc2.d/S14fsmond (starting)
/etc/rc0.d/K14fsmond (terminating)

Editing default values

If you want to run the daemon with values other than the default values, you must edit the daemon call in the rc script /etc/rc2.d/S14fsmond. Once you have edited the values, the POSIX subsystem must subsequently be terminated and restarted. If the values entered are inconsistent, the daemon will be terminated with an error message which will be output to the syslog logging file.

Test status

Examples showing tests to check if the daemon was started properly:

/ # /etc/rc2.d/S14fsmond status
fsmond is running (pid=25)

/ # /etc/rc2.d/S14fsmond status
fsmond is not running

/ # ps -ef |grep fsmond
ROOT    25     1  0 10:24:32 ?        00:00 [fsmond]

In case the daemon is not started, the error reason is normally given in the file /var/adm/syslog.

Advice on running the daemon

Generally speaking, the daemon should be started and ended automatically via the POSIX subsystem. In this case, the daemon runs as a background process under $SYSROOT.

It is possible to start and end a daemon using an rc script call but you should only do this exceptionally, e.g. when running a test:

/etc/rc2.d/S14fsmond stop
/etc/rc2.d/S14fsmond start

Console messages

%POS4030 FSMOND: WARNING! (&00)% ALLOCATION EXCEEDS WARNLIMIT ((&01)%) ON FILE SYSTEM "(&02)"

?POS4031 FSMOND: ATTENTION! (&00)% ALLOCATION EXCEEDS errorlimit ((&01)%) ON FILE SYSTEM "(&02)"

The POS4031 message can be answered with any entry, e.g. with tsn.

The daemon will remain in the waiting position until the POS4031 message is answered. Regular testing of other file systems will be suppressed.