SQLisAwE5OmE (9/13/2014)
When setting up mirroring with witness server, what exactly the role of a quorum?
Quorum is the process by which the current resource owner is logged within a set configuration. It's there to prevent a situation where more than 1 owner attempts to control a resource, in this case, a mirrored database.
SQLisAwE5OmE (9/13/2014)
Yes, if the witness and mirror disconnect from the principal it will go offline to protect the database.
SQLisAwE5OmE (9/13/2014)
I was in the impression, that if DR and Witness goes down, PROD still will be up and only downside is that mirroring will be disconnected and in suspended mode and the log will grow on the PROD side
Only if you don't have a witness, the database mirroring documentation is pretty clear about the ramifications of using a witness server. It has its benefits but also some restrictions
SQLisAwE5OmE (9/13/2014)
however, I was reading about the setup with witness server, and I read something like PROD will have downtime as well.
Yes, if the mirror and witness connections to the principal are lost, the principal runs exposed and goes offline.
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