Problems with connections to CICS Transaction Server.
If a TCP/IP subsystem fails, the CICS® Transaction Gateway tries to reconnect to TCP/IP when it becomes available again. However, if multiple TCP/IP stacks are in use on the z/OS® system the CICS Transaction Gateway cannot detect that a TCP/IP subsystem has failed unless all the TCP/IP stacks to which it is bound fail. Consider using the TCP/IP environment variable _BPXK_SETIBMOPT_TRANSPORT to control which TCP/IP stacks the CICS Transaction Gateway can bind to; for more details see the z/OS Communications Server: IP Configuration Guide, SC31-8775.