Resolution:
(W)arning message:
local_rtserver_unique_subject : {SRV.SMR./_remote_rtserver_unique_subject} TAL-SS-15169-W TsmrCbServerSrvGmdClientSubjectSetSubscribe: can't find subject </subject>. not adding any gmd clients from server </_some_other_rtserver_unique_subject>

Explanation:
Indicates that a remote_rtserver is telling the local_rtserver to add a new RTclient to an existing LB/GMD publisher from some_other_rtserver, but this local_rtserver does not have a publisher for the subject listed. This can be caused by a RTclient application disconnecting that was publishing at one time.