Putting Exchange into Maintainence Mode and bringing it back online again

** Fornote: This operation is for Exchange members which are not in a DAG - the process for a DAG requires additional steps that will be covered in a future post. **

We firstly drain the messages queues - i.e. all current messages in the queue will be sent, although new ones will be rejected temporarily:

Set-ServerComponentState  -Component HubTransport -State Draining -Requester Maintenance

Although we can also re-direct messages to another server temporarily:

Redirect-Message -Server -Target mbox02.mydomain.com

And finally we shutdown / suspend the Exchange services:

Set-ServerComponentState -Component ServerWideOffline -State Inactive -Requester Maintenance

You can now perform the necessary maintenance on the server - whether it be mailbox database restore, restart for updates etc.

When we are finished we start the Exchange services back up:

Set-ServerComponentState -Component ServerWideOffline -State Active -Requester Maintenance

And finally start the mail queue again:

Set-ServerComponentState -Identity -Component HubTransport -State Active -Requester Maintenance