Question: Can a 2008 SQL instance be used as the witness for a 2005 database mirroring setup?

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Can a 2008 SQL instance be used as the witness for a 2005 database mirroring setup?

Databases to be mirrored are currently running on 2005 SQL instances but will be upgraded to 2008 SQL in the near future. I have not tried this, need mirroring setup and was hoping to get a jump on the future upgrade.

My answer:

Yes, a SQL 2008 machine can act as witness for 2 SQL 2005 machines. When upgrading the systems from SQL Server 2005 to SQL Server 2008, the witness can be upgraded at any time (first, last, or in the middle).