Greetings!
My recommendation would be to follow procedures in the guide attached to this post.
First, manually trigger a failover to the Standby:
- Forcing a Commander failover (page 6)
Next, if the Commander will be replaced with the same part:
- Replacing a stack member (page 7)
Alternatively, if the Commander will be replaced with a different part:
- Removing a stack member (page 6)
- Replacing a stack member (page 7)