I've had this happen before. Here are the notes I jotted down
for the next time it happens:
________________________

Troubleshooting problems.

The servers communicate to eachother through an encrypted password.
Sometimes, if the TSM password is corrupted or if someone pokes around
in the wrong place in the Web GUI, it cross-server communications can
get messed up. Here are the steps to get it working again. 
NOTE: This does not work with TSMDMZ1, as the firewall will not pass
this traffic. You must still change your TSM password on the DMZ host
individually. 


Log onto MASTER TSMHOST and do a "q server" to see who he "manages". 

Check to see if they are still communicating. 
q subscriber 

On MASTER TSMHOST update the cross-server password to whatever you like
on all the servers on the list. 
update server SERVERNAME serverpassword=NEWPASSWORD 

Tell all the "managed" servers what MASTER TSMHOST's new password is. 
all: update server tsmserv1 serverpassword=NEWPASSWORD 

Get the managed servers to try to communicate. 
update subscribers 

Check in a minute to see if it is now communicating properly. 
q subscriber 
Additional hints: 

One of the most helpful screens when troubleshooting cross-server
communications is found in this help file. Learn it and it will save you
some headaches. 

        tsm: TSMSERV1A>help ANR0454E
        
------------------------------------------------------------------------
-------
-------
        ANR0454E Session rejected by server server name, reason:
        ANR0454E Session rejected by server server name, reason:
rejection reason.

        Explanation: The server has attempted to open a session with the
shown
        server. The session was rejected for the indicated reason.

        System Action: The operation fails.

        User Response: Check both the servers for any additional
messages that might
        further describe the reason the session was rejected. For a
reason of
        AUTHENTICATION FAILURE, ensure that all passwords have been set
correctly on
        both servers. The password for the server (set by SET
SERVERPASSWORD on
        server X) and the password in the server definition (set by
DEFINE or UPDATE
        SERVER X SERVERPASSWORD=) are the same password. For a reason of
        VERIFICATION FAILURE, use the QUERY SERVER command to determine
that the
        HLADDRESS and LLADDRESS of the target server are correct. If
they are not,
        correct them with the UPDATE SERVER command. If they are
correct,
        resynchronize with the target server by issuing the UPDATE
SERVER
        FORCESYNC=YES. For a reason of COMMUNICATION FAILURE ensure that
the target
        server is available and that TCPIP is available on both servers.
For a
        reason of NO RESOURCE, ensure that the receiving server is
enabled, has
        sufficient DB, LOG, and memory resource to support the source
server
        session. For a reason of INTERNAL ERROR, use the messages on the
target
        server to determine the problem and contact your service
representative.
        Retry the failing operation.

______________________

Ben