I was reviewing a paper on vCenter availability for 6.0 and it listed a watchdog service which monitors “VPXD” (the vCenter Server service) on the vCenter Server Appliance. I had seen the service before but never really looked in to it. With 5.5 the watchdog service (/usr/bin/vmware-watchdog) was only used to monitor vpxd and tomcat but in 6.0 the watchdog service seems to monitor some more services. I did a “grep” of vmware-watchdog within the 6.0 appliance and the below is the outcome, it shows the services which are being watched:
ps -ef | grep vmware-watchdog root 7398 1 0 Mar27 ? 00:00:00 /bin/sh /usr/bin/vmware-watchdog -s rhttpproxy -u 30 -q 5 /usr/sbin/rhttpproxy -r /etc/vmware-rhttpproxy/config.xml -d /etc/vmware-rhttpproxy root 11187 1 0 Mar27 ? 00:00:00 /bin/sh /usr/bin/vmware-watchdog -s vws -u 30 -q 5 /usr/lib/vmware-vws/bin/vws.sh root 12041 1 0 Mar27 ? 00:09:58 /bin/sh /usr/bin/vmware-watchdog -s syslog -u 30 -q 5 -b /var/run/rsyslogd.pid /sbin/rsyslogd -c 5 -f /etc/vmware-rsyslog.conf root 12520 1 0 Mar27 ? 00:09:56 /bin/sh /usr/bin/vmware-watchdog -b /storage/db/vpostgres/postmaster.pid -u 300 -q 2 -s vmware-vpostgres su -s /bin/bash vpostgres root 29201 1 0 Mar27 ? 00:00:00 /bin/sh /usr/bin/vmware-watchdog -a -s vpxd -u 3600 -q 2 /usr/sbin/vpxd
As you can see vmware-watchdog is ran with a couple of parameters, which seem to different for some services. As it is the most important service, lets have a look at VPXD. It shows the following parameters:
What the above parameters result in is the following: the service, named vpxd (-s vpxd), is monitored for failures and will be restarted twice (-q 2) at most. If it fails for a third time within 3600 seconds/one hour (-u 3600) the guest OS will be restarted (-a).
Note that the guest OS will only be restarted when vpxd has failed multiple times. With other services this is not the case as the “grep” above shows. There are some more watchdog related processes, but I am not going to discuss those at this point as the white paper which is being worked on by Technical Marketing will discuss these in a bit more depth and should be the authoritative resource.
** Please do not make changes to ANY of the above parameters as this is totally unsupported, I am mere showing the details for educational purposes and to provide a better insight around vCenter availability when it comes to the VCSA. **