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I currently have one on-premises Exchange 2010 Std server sitting on a Windows 2008 R2 Entreprise. The server is backed-up on tape and now I've been asked to add an off-site replication for businness continuity and disaster recovery. The setup is fairly small: about 20 mailboxes on one database.

High availability is not a requirement, I just need to be able to manually activate the off-site server if something really bad happens on the main site.

We have already have a domain controller on a remote site and I was planning to add another one with Exchange 2010 Std/Windows 2008 Ent, setup an active/passive DAG an replicate my database. Since this would be a two node setup, I would also use a file server on the main site as the witness.

My main concern is that I only have one NIC on the remote server, so there would only be one connection between the two nodes. This is a WAN 20 Mbits/s symetrical connection through an IPSec VPN, the ping is well below 100ms (usually <10ms).

I've read many articles on the subjects but all of them assume that you have two NICs on each server. Would a single-NIC connection be an issue in my case?

What about DAC in a two-nodes setup? Would that fit my requirement thatthe off-site node should only active manually?


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I've run similar setups to the one you described - only having the single NIC I've not had any issues – Aceth Jan 9 '13 at 12:42
@Aceth thanks for the feedback! – Guillaume Jan 9 '13 at 13:17
No problem glad to help :) – Aceth Jan 10 '13 at 10:47
up vote 2 down vote accepted
  1. Number of NICs: This is really a question of number of networks, not network adapters. The recommended way is to have a completely separate, dedicated network for replication. It's not an requirement.
  2. To run DAC with two Exchange nodes you'll need a witness fileshare (which should be put at the main site). This way the database will always stay up at HQ (most votes).
share|improve this answer
Thanks for the answer pauska! – Guillaume Jan 9 '13 at 13:22

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