Resolution:
Description:
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When you specify "localhost:port" or just "port" for listen port parameter, for example: "listen = tcp://localhost:7222" or "listen = tcp:7222",  you will notice some changes in the EMS server log when starting the EMS 6.3 server.

Resolution:
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EMS 6.3 supports IPv4, IPv6 and mixed IPv4/IPv6 environments.  When you specify "localhost:port" or just "port" for listen port parameter, for example: "listen = tcp://localhost:7222",  the EMS 6.3 server will treat it as "any" address of the default interface and  try to listen to both IPv6 and IPv4 with this 'any' address on the given port.

EMS 6.3 shows  0.0.0.0 for the "any" address of default interface for IPv4 and [::] for the "any" address of default interface for IPv6.

The EMS server will try IPv6 and IPv4. If it fails to setup a listen port for *one* of the addresses it will issue an error message indicating the failure reason and a warning message. If it fails to setup the listen port for both addresses it will fail to start.

When the listen port for both IPv6 and IPv4 addresses start successfully, the EMS server shows the following log entry:

2012-03-07 14:33:27.598 Accepting connections on tcp://{hostname}/[::]:9222.
2012-03-07 14:33:27.598 Accepting connections on tcp://{hostname}/0.0.0.0:9222.

Here are two examples:

1). If the IPv6 address is not supported on this system, the listen port for IPv6 address fails to start, while the listen port for IPv4 address does start. The EMS server shows the following log entry upon starting up:

2012-03-07 13:46:25.078 SEVERE ERROR: Unable to open socket for listening: 97 (Address family not supported by protocol).
2012-03-07 13:46:25.078 WARNING: Unable to accept connections on tcp://{hostname}/[::]:7222 - Error 201 - Initialization failed
2012-03-07 13:46:25.078 Accepting connections on tcp://{hostname}/0.0.0.0:7222.

2). If the listen port for the IPv4 address is already being used while the listen port for IPv6 address starts up, the EMS server shows the following log entry upon starting up:

2012-03-08 10:13:56.574 ERROR: Binding connection to TCP port 7222 failed:98 (Address already in use).
2012-03-08 10:13:56.574 WARNING: Unable to accept connections on tcp://optimist.na.tibco.com/0.0.0.0:7222 - Error 201 - Initialization failed
2012-03-08 10:13:56.574 Accepting connections on tcp://{hostname}/[::]:7222.

Changes for the default interface when starting an EMS 6.3 server.