You have an Exchange Server 2013 organization that contains two servers. The servers are configured as shown in the following table.

EX1 and EX2 are members of a database availability group (DAG) named DAG1. You have a database named DB1 that replicates to EX1 and EX2.
EX1 fails.
You discover that DB1 does not mount on EX2.
You view the status of the mailbox databases as shown in the following table.

You need to ensure that the database attempts to mount on EX2 if EX1 fails.
What should you change?