Recently, I was troubleshooting a VCD 10.4 installation with three cells which experienced very slow response times during operations such as Power on/off a VM.

Looking throw the log files soon revealed messages such as:

ERROR | ActiveMQ BrokerService[] Task-15 | TransportConnector | Could not accept connection from tcp://:47990 : javax.net.ssl.SSLHandshakeException: Received fatal alert: certificate_unknown

To resolve this issue, we’ve checked if the certificate is expired by running the following command on one of the cells:

/opt/vmware/vcloud-director/bin/cell-management-tool jms-certificates --status

The following part of the command result shows, that all of the 3 cells didn’t had a valid certificate:

To generate new certificates, we’ve run the command:

/opt/vmware/vcloud-director/bin/cell-management-tool jms-certificates --certgen --force

Afterwards, we restarted all cells:

service vmware-vcd restart

This fixed the issue in this environment.