Running Zarafa Community in a 2GB Linode Server

I am running ClearOS 7.2 on a basic Linode cloud server. As configured it has 1 cpu core and 2 GB of RAM. It works just fine most of the time. I have had three instances where I couldn't log into the server from my email application (thunderbird, webapp & outlook 2016). Using webapp I see a message 'Unknown MAPI Error: MAPI_E_DISK_ERROR'. If I reboot the server the error goes away. I sent a support request to Linode and received a response within two hours! The tech indicated the hardware checked out fine. The tech also suggested that the server is over-using its allotment of RAM and is dipping into SWAP. The next time it fails I will look to see if any of the zarafa servers have failed.

In the meantime, I don't need all of the zarafa servers. To reduce RAM usage I can manually stop the webapp service, the ical service, the search indexing and the quota service. A chkconfig --list shows zarafa-ical, monitor and search to be all off for all runlevels. Obviously they are starting. Is there a .conf where I can stop them from starting? Also, where can I stop the web server for webapp from starting on a reboot?

The main purpose of this ClearOS installation is to handle email. I will try to remove other servers and services to reduce the RAM footprint. It is not heavily used (2 email accounts at this time) but it needs to be reliable. Any suggestions helpful.