I have the same question. Have two Exchange 2016 servers in a DAG both running on Windows Server 2012R2. Need to get the Exchange databases on servers running Windows Server 2016. Can’t add new Exchange server to DAG if different OS. Can I create new DAG, add new Exchange servers and migrate databases? If so, how to configure subnets?

I would like to create a new DAG and a mailbox database on the 2016 servers and then move any mailboxes that must remain on prem to the new DAG. I would then decommission the 2010 Exchange servers as they are approaching end of life.

I would like to setup a the new 2016 DAG without and administration point. The 2016 servers have been created with 2 nics each and with the correct settings for the replication NIC.

The replication subnet on all 4 servers is the same, example 192.168.1.0/24.

Question 1 – If i create the 2016 DAG using the same replication subnet, is that going to mess up the existing 2010 DAG?

Question 2 – Do you recommend setting up the DAG manually or letting Exchange auto configure.

Thanks in advance for your feedback.

You need to enable DataCenterActivation mode for this to work correctly. But this will require a (small) manual task to enable smooth/correct failover.

E.g. if (AD)site A goes down, your mailboxes will be mounted on your passive Exchange servers, but exchange will not mark the servers in Site A as down. You should then run ‘stop-databaseavailabilitygroup -identity -ActiveDirectorySite ‘Site A’

this will enable full functionality of Site B even without access to the FSW and no hiccups when Site A comes back online. after Site A is deemed fully only again, you can run ‘restore-databaseavailabilitygroup -ActiveDirectorySite ‘Site A’

I have an existing 2 node DAG (1 on-prem and 1 on DR site). How can I accomplish adding a 3rd node to the existing DAG? How do I properly setup the new Exchange server 2016 as a member of the existing DAG?

I am looking for a clear definitive answer on this one. I have a 2 node DAG and a FSW. Node A and FSW are in primary datacenter, Node B is in secondary datacenter. We recently moved all of our DBs active copies to the secondary datacenter on Node B.

We then lost our primary datacenter, so Node A and FSW went completely dark. What would the expected behaviour be here for the mounted DBs in secondary datacenter? As one DAG member was offline along with FSW, shouldn’t these active DBs have dismounted automatically?

I am told they remained mounted from the console/GUI perspective but we had user complaints they couldn’t access email. I am seeing contradicting information on what will happen if you lost the link between your 2 DCs and your active DBs are on a different site to the FSW?

I’m reading your post(s) about DAG, I read also on other sites (your posts are always clear and well explained).
A DAG seems to be useful if we want to provide high availability for users, on the primary office site, using a quorum witness.

In case I have only one exchange server on the primary Office site, and would like a second Exchange server in a DR site (no users on that site), is it possible to have a DAG that will have both servers (ExchangeOffice and ExchangedDR) as members ? Sites have different IP range, Sites have their own domain controler named DC.domain.local and DR.domain.local.

Will this configuration assure me that users will have access to their emails in case the ExchangeOffice server goes down (slower acces because of the inter-site link) ?

In case the Office site goes down, with no more quorum (located at the office that is no longer working) will the ExchangeDR database start with an unreachable quorum ? Is the solution (I think you mentioned it) of having a Quorum on a shared folder on azure the solution so quorum will always be reachable ?

I think this is what you mentioned as “site resilience”, so I basically supposed there is one DAG with members on two different sites but I doubt it is as easy as that.

thank you if you can just clarify this point so I will stop beeing stuck for nothing.

Terry

Customer have a Primary Exchange, and would like to have another in DR site, the intranet bandwidth is about 30mbps. ( wireless connection between 2 sites )

possible to run it ?

Is it worth sticking a new server on there or just pointless replication?

thanks…