can i install Exchange 2010 DAG with any other exchange componenets

  • Thread starter john.yassa
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i need to aks if i can install exchange 2010 DAG with any other exhcnage component as CAS or HUB on the same server

or the DAG has to be on server alone joined the domain

john yassa

Matt Huxtable

The DAG can co-exist with the Hub Transport and Client Access roles quite happily. This means you can now create a redundant Exchange deployment using just two Exchange Servers, both of which run the DAG, CAS and HT roles.

However if you have the CAS on the DAG members, you won't be able to use Windows Network Load Balancing (WNLB) on the server to load balance and failover your CAS servers. Failover Clustering will be installed on the DAG members to provide the underlying framework for the DAG, and you can't use WNLB and clustering services on the same server.

For CAS failover you will therefore need to use one of:
a hardware load balancer in front of the CAS boxes (f5, Cisco, Barracuda etc) publish the CAS boxes through a Forefront TMG array, which will load balance the HTTP traffic. It won't load balance the Outlook MAPI traffic though, so for that you'll need a separate load balancer or to force all Outlook users into Outlook Anywhere mode internally, so they connect via the TMG array over HTTP. the "poor man's" solution - which is two round robin DNS records with a low TTL (~5 minutes). You then remove one of the DNS records when a server fails

I personally prefer the hardware load balancer approach because most load balancers support additional affinity options compared with WNLB and they can support internal MAPI traffic.


Gulab Mallah

I Agree, you can have multiple role installed on the same server

Gulab | Skype: gulab.mallah

Jonas Andersson [MCITP]

It's NOT recommended to have both DC role and Exchange roles installed on same server

Jonas Andersson MCTS: Microsoft Exchange Server 2007/2010 | MCITP: EMA 2007/2010 | MCSE/MCSA Blog:
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