As Kevin said you can put it anywhere as it's just a file share. There is no requirement to make sure the DAG operating system and FSW operating system versions match. The only thing I would say about putting the FSW on a domain controller is that you are giving the Exchange Trusted Subsystem group a lot of permissions in Active Directory (it has to be made a member of the local administrators group on the FSW server) - it may or may not be a concern in your environment.
From: xyz [mailto:x...@minneapolis.edu] Sent: 22 January 2011 03:05 To: MS-Exchange Admin Issues Subject: File Server Witness 2010 SP1 Greetings, We have EXCHANGE 2010 SP1 two host DAG on single site (no DAC). With only two DAG hosts, we clearly need the FSW on line on a "third" box for any major failover quorum. Per MS documents: We recommend that you use an Exchange 2010 Hub Transport server in the Active Directory site containing the DAG. This allows the witness server and directory to remain under the control of an Exchange administrator. In my case we manage the whole network and AD environment, so this is less of an issue. Installing a third EXCHANGE box is an option, but not sure I need to go this way right now - as there are workarounds - and managing another box just for FSW is something I hope to avoid. Could we install the FSW on one of our DCs? This would make management easier, as we always know DC status quickly. But not finding this in the MS documentation yet as to if this would be a concern. Thanks for any suggestions. Dana --- To manage subscriptions click here: http://lyris.sunbelt-software.com/read/my_forums/ or send an email to listmana...@lyris.sunbeltsoftware.com with the body: unsubscribe exchangelist --- To manage subscriptions click here: http://lyris.sunbelt-software.com/read/my_forums/ or send an email to listmana...@lyris.sunbeltsoftware.com with the body: unsubscribe exchangelist