CAUSE 1
The key on the FMS was using a DHE-DSS-AES256-SHA cipher. The key on another FMS at the site that was not showing the same problem was using a AES256-SHA cipher.
CAUSE 2
The key file is missing in the key store.
RESOLUTION 1
A self-signed certificate is being used.
The output of the "openssl s_client -connect hostname:8443 -debug -showcerts" command indicates that the protocol used by the self-signed certificate is TLSv1 and the cipher is DHE-DSS-AES256-SHA
Regenerate the self-signed certificate on the FMS using RSA encryption; for more information refer to How to generate a new self-signed certificate for the Foglight Management Server (4378707).
RESOLUTION 2
The key file is missing in the keystore, only the certificate is available.
Solution 4254114 provides the detailed steps to import a 3 party certificate.