Are Multiple Witnesses possible in a mirroring scenario

Question

Hello and thanks in advance for your reply's.

We have 2 locations we want to mirror from/to and provide for complete disaster recovery. Let's call Corp. location A and the Distribution Center location B. I would like to implement mirroring with high-safety as follows. This way if either location goes down, automatic fail over will occur to the other location. It is possible in a mirrored scenario for both the Principal and Witness to fail and go down simultaneously.

Server 1: A(Principal)

Server 2: A(Witness)

Server 3: B(Mirror)

Server 4: B(Witness)

Is this possible and what special configurations must occur to make this work.

Regards, 

Answer 1

AFAIK you cant set up multiple witnesses for single mirroring session. So, you could either 'secure' witness by setting it up on cluster environment, or you could try setting up witness monitoring where you would check for the witness availability and issuing failover in proper scenario.

So, if principial and witness go down at the same time, dont think you have automatic failover option out of the box.

 

MC

Answer 2

No, you can only have 1 witness. Should you be unable to achieve a quorum between the principal and the mirror, the principal and the witness, or the mirror and the witness your principal will be suspended.

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Answer 3

No - only 1 witness, 1 principal and also only 1 mirror.

Answer 4

No not possible you must have only one witness.