Forum Discussion
Chris_18327
Nimbostratus
NimbostratusHelp Needed for Health Check
Hello,
I am using F5 LTM to load balance our syslog servers. I would like to implement a health check to verify that syslogd is running on the remote host (Linux). I would appreciate any ideas that someone may have. My first thought is to ssh to the box and check for the syslogd process, but I am not sure of the best approach for this.
Any ideas or help will be much appreciated.
Thanks.
- The_BhattmanI think you hit it on the nose.
- dennypayne
Employee
If a tcp port check to the syslog port is not sufficient to tell whether syslogd is actually functioning correctly then I agree with cmbhatt. Just write a shell script which ssh's to the box, checks for syslogd (ps or whatever), and returns "UP" if it succeeds. Then just create an external monitor type that calls the script. I would back the default monitor interval off from 5 seconds to something a little less aggressive though.
A tip: the regular shell variables $1, $2 correspond to the pool member and port, respectively, and $3 is any argument called in the monitor definition in the GUI. But LTM is totally IPv6 internally, so $1 will be rendered with an extra "ffff" which may cause you headache wondering why the ssh to the pool member IP fails. I would take care of this by assigning the IP to a variable, stripping off the IPv6 stuff, and then performing ssh to the variable name:
MEMBER=`echo $1 | sed 's/::ffff://'` 2>/dev/null
has worked for me before.
Hope that helps!
Denny - dennypayneI just found Deb's excellent article which goes into more detail about external monitors: (Click here)
Denny
