AIX 6.1 TL7 includes IBM Systems Director Common Agent (cas agent). It is installed as part of the System Management Client Software bundle which is part of the default install options.
Unfortunately, this new component introduce 2 small bugs including one that could fill up root filesystem (/).
After installing TL7 and at system reboot, the Director agent is automatically enabled.
meyawi.com@root:/> oslevel -s
6100-07-00-0000
meyawi.com@root:/> lssrc -s cas_agent
Subsystem Group PID Status
cas_agent 7667718 active
meyawi.com@root:/> lslpp -L cas.agent
Fileset Level State Type Description (Uninstaller)
----------------------------------------------------------------------------
cas.agent 1.4.2.32 C F Common Agent Services Agent
The subsystem wasn’t existing at previous level, for example at AIX 6.1 TL6 SP1 :
meyawi.com@root:/> oslevel -s
6100-06-01-1043
meyawi.com@root:/> lssrc -s cas_agent
0513-085 The cas_agent Subsystem is not on file.
Let’s see each bug case…
Bug 1 : CAS Agent is filling up root filesystem (/)
As you may have noticed, your root filesystem used space is growing and a strange file have been created in /dev directory.
meyawi.com@root:/> ls -ltr null*
crw-rw-rw- 1 root system 2, 2 May 12 19:10 null
-rw-r--r-- 1 root staff 45445 May 12 19:10 null 2>&1
Let's have a look at cas_agent startup script which is causing this issue.
meyawi.com@root:/> vi /var/opt/tivoli/ep/runtime/nonstop/bin/cas_src.sh
...
else
CAS_SRC_LOG=”/dev/null 2>&1”
fi
...
We could resolv this by editing the line above as follows for example :
meyawi.com@root:/> stopsrc –s cas_agent
0513-044 The cas_agent Subsystem was requested to stop.
meyawi.com@root:/> vi /var/opt/tivoli/ep/runtime/nonstop/bin/cas_src.sh
...
else
CAS_SRC_LOG=”/dev/null”
fi
...
meyawi.com@root:/> ls "/dev/null 2>&1"
meyawi.com@root:/> rm "/dev/null 2>&1"
meyawi.com@root:/> startsrc –s cas_agent
0513-059 The cas_agent Subsystem has been started. Subsystem PID is 8323268.
Reference :