Proper DAG Site Resiliency

WFleck_parente
WFleck_parente used Ask the Experts™
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I'm having trouble wrapping my head around a clients DAG config.  They have a 5 Node DAG, 3 MBX servers in Primary Site and 2 MBX in Secondary site, no FSW.  Cluster Quorum is Node Majority.  When Primary site goes down, DAG copied in Secondary site goes Offline as Quorum is lost. What can I configure to have the DAG Copies in the Secondary site to stay operational?  Even if I put a FSW in the Secondary Site, the Cluster will ignore is because it's a 5 node cluster.
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IvanSystem Engineer

Commented:
Hi,

is secondary site in another  AD site or same site as Primary?

Regards,
Ivan.

Author

Commented:
Yes, the secondary site is another AD site.
Hardik DesaiIT Architect and Trainer

Commented:
What do you mean by Primary site down? Is the network link connecting the 2 sites is down or the systems hosting Exchange DB in primary site are down.

If the link is down, the node in primary site will continue to work as is, there will only be increase in copy queue length.

If the systems hosting the active DB in primary site are down, the quorum is lost. Now as there are only 2 DAG nodes left in the secondary site, you will need to set FSW and then manually bring the DBs online using recovery methods.

Remember, HA is always automatic, DR is manual.
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Author

Commented:
There was a controlled shutdown at the primary site where the DAGs were failed over to the Secondary site and the 3 MBX servers in at the Primary site were shut down.  As stated, in this test, there are only 2 nodes left in the DAG and quorum is lost.  I know that a FSW would need to be setup in the Secondary site and the DBs brought up manually in a true DR situation.  

The thing I was wondering about but was is there another way to keep DBs online in a controlled test at the primary site where the DAGs were failed over to the Secondary site and the 3 MBX servers in at the Primary site were shut down?
IT Architect and Trainer
Commented:
You have to manually initiate DR is absence to quorum (FSW or extra node).

Author

Commented:
Thank you for you assistance.

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