We are doing a POC at our customer.Exchange environment of customer is comprised of 4 mailbox server in a DAG.
mbx1, mbx2, mbx3, mbx4. The databases has been mounted only on two servers (mbx1 and mbx3).
We have create archiving on these two nodes but it is not possible to create tasks on the others.
So How can I doing fo create task on the remaining servers.
Take a look at this technote:
Using Exchange Server database availability groups
To ensure that the mailboxes you enable for archiving are always available to Enterprise Vault, you must set up archiving for all the DAG member servers. You must also target all the DAG member servers within one Enterprise Vault site.
To set up Exchange mailbox archiving for a DR-only server
When all DAG member servers are set up for archiving, database and server failovers do not interrupt mailbox archiving.
I hope this helps.