Handling CLSDST(PASS)
A back-end system can end a network session with a z/OS® Communications Server CLSDST(PASS) request.
This indicates that the back-end will reestablish a session with the front-end using a different PLU name (a third-party PLU). The front-end system detects reestablishment of the session by receiving an unsolicited bind request; so when the back-end system ends a session, it is important for it to indicate that an unsolicited bind is to be expected.
Note: To determine whether a lost session was caused by a CLSDST(PASS)
request, a FEPI application can issue a FEPI INQUIRE CONNECTION command.
If the value of LASTACQCODE is X'32020000', the back-end
system issued a CLSDST(PASS) to unbind the session.
The three most likely scenarios are described in the following sections.