Not really an original thing, but I keep forgetting it. Maybe it helps others.
When FreeSWITCH loads some modules such as mod_callcenter, mod_fifo or is not using any kind of ODBC it uses SQLite as database handler. SQLite stores its database in /var/lib/freeswitch/db (generally). Depending on your hard disk, the I/O may become a bottleneck.
So far the only way of creating a highly available cluster with a floating IP approach was using bare metal serves in any datacentre, until Digital Ocean arrived. As far as I know, Digital Ocean is the only VPS datacentre who provides floating IP services. Floating IP is very handy, it is the key to create a highly available cluster by moving a floating IP under demand among some selected servers.
I have already explained how to configure a FreeSWITCH HA Cluster. In this article, I will only explain how to configure the Digital Ocean's Pacemaker resource.
In this post, I am going to talk about how to configure FreeSWITCH in a high availability active-passive schema. The active-passive approach will share a floating IP between your VoIP switches and when one gets off-line, the passive one will take control over the IP and it will get the load. This article will assume the following: