How to set up a failover solution for the unblu application to maintain high availability
I would like to have a failover solution for the unblu application so that a high availability of service can be maintained.
A failover can be described as an operational process of switching between two nodes or severs, a master/primary and slave/secondary one, in the case of downtime or system failure. Unblu does not support load-balancing or clustering. Therefore, to maintain a failover solution you may follow one of the following ways; depending on your infrastructure and available resources:
- Hot Failover: here two or more parallel servers run continuously, but only one of them is active (in production). All others are in a hot standby state. The hot-standby servers are configured exactly the same as the active server and synchronized to take over the production system at any time.
- Warm Failover: a standby server, which is configured exactly the same as the active server, is quickly available in the event of production system failure to take over the production system at any time.
- Cold Failover: in the case of primary server failure, a secondary server is started up, configured as the primary one, and brought online.(So this server takes over the production system.)
If you would like to set up an automatic failover, you may consider the following as a guide (check-list):
- Get a secondary server: depending on which failover solution you wish to implement (Hot Failover/Warm Failover/Cold Failover).
- Synchronise the unblu server configuration between primary and secondary servers.
- Have some tools to monitor server status.
- In the event of system failure, depending on the failover solution, get the secondary server ready to take over the production system.
- Set up DNS Failover: depends on your infrastructure. You may need to configure/set your DNS to point to the new server.
- Perform some testing.