Resolution:
This warning message which would appear in the RTserver trace file indicates that Logical Connection Name could not be properly expanded and therefore the rtserver-to-rtserver connection that it was meant to represent did not get created.

This will lead to a mis-configuration of your RTserver cloud and possibly unexpected message routing.

The complete set of trace messages (with a trace_level of Info1) would look something like this:
TAL-SS-10099-I Connecting to other RTserver processes.
TAL-SS-10101-I Constructing connect element list.
TAL-SS-10087-I Adding 'mynodename:5102' to connection element list.
TAL-SS-00179-W Could not expand lcn &ltmynodename:5102>: 'doesn't exist'.
TAL-SS-10088-I Failed to expand server name. &ltmynodename:5102>.

   This problem is the result of a typo/misunderstanding in the rtserver.cm files. Specifically in the definition of the server_names option. A fully qualified logical connection name (LCN) is defined as
   &ltprotocol>:&ltnode>:&ltaddress>  
As documented this LCN can be shortened to either
  &ltprotocol>:&ltnode>
   &ltprotocol>, or
   &ltnode>

However, the LCN cannot be shortened to
  &ltnode>:&ltaddress>
This representation cannot be parsed correctly as SmartSockets tries to use the &ltnode> as a protocol and therefore looks for a registered link-driver to implement that protocol.
    
Note that based on the catalog number, TAL-SS-00179-W, this event is treated as a warning rather than as an error and therefore the system continues to run, and you do not receive any additional alert to tell you that your system is potentially compromised.