Hi,
In existing environment, we have two cluster nodes with heartbeat.The system is able to do failover, but still there is a short downtime. We have a backend process that takes around 20 hours. There will be a problem even if the downtime is short.
Our company is working on improving HA on our existing environment. The question is that whether upgrade could provide Zero downtime for latest OS/SQL version.
Existing environment
- Windows Server 2012
- SQL Server 2008 R2