Restarting MSC TCP/IP links after errors

If an IMS system or an MSC TCP/IP link terminates unexpectedly, you need to confirm that the MSC TCP/IP link has also been cleaned up properly in the remote IMS system.

In the event of a failure, IMS attempts to clean up the MSC TCP/IP links at both the local and remote site; however, if the failing IMS system is unable to notify the remote site of the failure, the remote site might not clean up the link.

To determine if a link has been cleaned up in the remote IMS system, you can issue either the type-1 format /DISPLAY LINK command or the type-2 format QUERY MSLINK NAME(linkname) command.
After an MSC TCP/IP link terminates at a local site, if the remote site does not also clean up the link, issue a /PSTOP LINK FORCE or an UPDATE MSLINK STOP(COMM) OPTION(FORCE) in the remote IMS system.
If the link is restarted in the local IMS system before either the link or socket connection is cleaned up at the remote site, the link or socket connection is cleaned up at the remote site during restart processing.
To restart a TCP/IP link after an IMS system is started, issue either an /RSTART command or the UPDATE MSLINK START(COMM) command.
To set a stopped MSC TCP/IP link to its coldstart status, issue either the type-1 format command /CHANGE LINK COLDSESS or the type-2 format command UPDATE MSLINK SET (SYNCOPT(COLDSESS)).
The link must be stopped first. When specifying the COLDSESS keyword, the SYNCSESS or FORCSESS keyword must also be specified.