telnet to a port on RHEL 6 : Connection closed by foreign host after a few seconds
 

[root@10- ~]# telnet 78.bb.34.56 5672
Trying 78.bb.34.56
Connected to
Escape character is '^]'.
Connection closed by foreign host.

The connection gets closed after a few seconds.What exactly does that signify?

I'd appreciate any pointers.

Not much. A service of some type is running on the designated port but not compatible with the telnet protocol. Many use telnet as a quick check to test a running service. By the way the registered IANA service on port 5672 is ampq.