To install a ZenPack on Zenoss 5.1 and later, you are going to need to stop the zenoss services, restart a couple services that are needed to install the ZenPack, install the ZenPack, and then restart the Zenoss service.

Stop Zenoss.Core :

serviced service stop 

Make sure the service is stopped by running the following command.  When it reports back the Zenoss is Stopped, then continue.

 if ( serviced service status Zenoss.Core | awk '{print $3}' | grep -q Stopped) ; then echo "Zenoss is not running!" ; else echo "Zenoss is not Stopped!" ; fi

Or you can run this command, just make sure it says it is stopped.

serviced service status zenoss.core

Create a Snapshot

serviced service snapshot Zenoss.core

Start the following three services

serviced service start Infrastructure
zeneventserver
Zope

serviced service start Infrastructure
serviced service start zeneventserver
serviced service start Zope

Change directory to tmp, make sure you put the zenpack in /tmp

cd /tmp

Install the Zenpack

serviced service run zope zenpack-manager install *.egg

Example:

serviced service run zope zenpack-manager install ZenPacks.zenoss.MikroTik-1.1.1.egg

Restart the Zenoss Service

serviced service restart zenoss.core

Log into Zenoss and check it.