This browser is no longer supported.
Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(275.2, 57.00000000000001%, 36%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EM%3C/text%3E%3C/svg%3E)
Hello
I have Microsoft Exchange 2016 with DAG configuration , I have 4 Exchange nodes and DAG members in HO , I am planning to implement new Exchange 1 node in DR with Different subnets than HO and configure Dial tone recovery in DR site.
Is it doable?
If HO became down shall i rely on DR Exchange server with Dial tone DB to continue my work and move my MX record to DR site?
I need to know what is the best practice to this scenario?
I don't want to join the Exchange DR node to the DAG.
I recommend you add the DR server to the DAG or not use a dial tone in this scenario
You can do what you planning of course, . Assuming that DR server has the capacity for the number of users, that will work.
However The DAG isnt really an issue here with Dial Tone Databases, however how do you plan to recover all the data from the Dial Tone database once service is restored to the DAG? That wont really work well.
My problem i have only 1 node in DR and 4 nodes in HO , the quorum will be effected if the link between HO and DR became down and the whole cluster/DAG will be down.
Can you avise?
Hi, The Quorum will not be affected if link goes down. You will have 5 nodes, 4 in the primary data center, so you will still have quorum.
If you went this way, you should implement DAC Mode:
and do a datacenter switchover if ever required ( the entire primary data center is down)
If you can't do this, then I wouldnt set up a single stand-alone DR server at all honestly.
The Quorum will effect as if i have any downtime in HO and all the 4 nodes will not be accessible so the quorum will be affected,
I want to have a DR solution in case the network/connection between HO and DR became down
Hi, as mentioned, I would add the DR node to the existing DAG then. I do not recommend dial tone in this scenario.
How many nodes shall i add to DR?
Personally, I would add at least 2 if you can.
so if i add 2 nodes in DR so total vote will be 4+3+1=8
quorum=8/2+1=5
If the HO is down also still cannot achieve the quorum.
please correct me if i am wrong and where is the role for Dynamic quorum?
You have 4 nodes now, if you add 2 , you have 6 nodes, not 8.
The File Share Witness is not counted as unless needed, i.e. you have less than half the nodes.
If the primary goes does down, then you have to use the datacenter switchover doc to bring the quorum up in the DR center:
Dynamic Quorum works if you lose nodes one or or two at a time and quorum can be automatically maintained, however , the primary data center suddenly goes down and you lose all 4 nodes at once, dynamic quorum will not have the time to be invoked and won't apply
https://practical365.com/windows-server-2012-dynamic-quorum/