my company are currently discussing our HA and DR strategy for one of our core systems that's going to run on a MS SQL2008 server. The RPO is 0% lost transactions and the RTO has to be at an absolute minimum.
We have two servers that have solid state drives in them at our main datacenter. We've created a cluster for the servers using VSA and HP technologies. We have SQL running on the cluster. We're happy with this as our HA solution and with fail-over time. It's been proposed that we couple this SQL cluster with SQL mirroring to our DR site.
We're currently in the processing of extending our network to our DR site. Everything will run on the same subnet. I'm in discussions with our networking team and trying to figure out if we should create a third node of our cluster at the DR site and use that instead of mirroring.
They're reluctant to do this stating the following:
"if the VSa gets isolated the site will go down"
"there is no transparent failover"
"clustering doesn't accomodate for database corruption"
The corruption isn't a concern to me as we'll be doing daily DBCC checks on a staging database. The other two points I'm not sure if they're correct.
Can someone give me some advice on the pros and cons of these two solutions please?
Thanks in advance for the assistance.