This expressway cluster is in a partitioned state

[RL5901]

We have not used our Expressways in a while. We have version 12.5.7.  I am tasked with getting them running again. When I gained access to the two Expressway-Cs I see a message:

Warning: This Expressway cluster is in a partitioned state. Do not make any configuration changes until the cluster is operating normally. See Clustering page.

When I go to the Clustering Configuration page I see the following:

Next to the primary...

Next to the secondary...

Both Expressway-Cs are on the configuration page. Cluster database status is "Active". Cluster Address Mapping is OFF. Both Expressway-Cs are accessible through the Admin Web GUI. 

I have been trying to find a reference to this message in documents online and have found none. Is anyone familiar with the message or what the instructions are to fix it? 

[TechLvr]

Have you rebooted your secondary Exp C? A reboot usually clears these types of issues. 

[RL5901]

I have tried both a restart and a reboot of the secondary Expressway-C and neither cleared the message. But I believe I might know what could be the problem. The Expressway-C secondary under Clustering shows "Certificate: Invalid" next to the Expressway-C primary, now (post reboot). 

[TechLvr]

@RL5901 

On the clustering page, can you set the "TLS Verification mode" to "Permissive" and reboot your expressway C cluster again? This way the peers won't check each other's certificates for clustering. 

If you do have a requirement to enable TLS between Exp C nodes, you will have to fix the certificate issues. When you generate a CSR, on each node, let the CN name be your Exp C cluster FQDN, and the Subject Alternate Name be the FQDN of your expressway C.