In this tutorial, we’ll see how to set up a Database Availability Group (DAG) that makes the Exchange Highly Available (HA) databases available.
This feature of Exchange makes it possible to put the databases that host the mailboxes in high availability, the databases replicate in “real time”.
This solution ensures high availability of Exchange messaging services.
A DAG consists of at least two Exchange servers.
Personal opinion: it is essential for me to set up a DAG when we want to host its Exchange infrastructure, the DAG will help ensure the HA databases that also facilitates maintenance tasks. With a DAG, it is “feasible” to do daytime maintenance tasks on an Exchange infrastructure with no downtime.
Here are the prerequisites for setting up a DAG:
- 2 mini servers with the same version of Exchange and ideally the same level of patch.
- 2 network cards (LAN / Replication Networks), disable the DNS record for the network card dedicated to replication.
- the same number of disks / partitions with the same letters.
- sufficient volumetry on the disks to accommodate the databases.
- 1 server with a folder for quorum
Servers do not have to have the same CPUs and the same amount of memory. It is possible to mix VM / physical machines..
The following tutorial: Exchange 2016: Installation and Configuration will guide you through the installation.
In the administrative console, both Exchange servers must be present: