Making IMS ready
Use the IMS /START command
with the DC keyword to make IMS ready to receive VTAM® logon or BIND SCIP (session
initialization) requests.
The DC keyword initiates IMS data communications processing, opens the VTAM access method control block
(ACB) if it is not already open, and enables the IMS VTAM logon
exit. Any logon requests received by VTAM before
the IMS /START DC command
is issued but after the ACB has been opened are queued in VTAM until the /START DC command
is completed. If VTAM is active
when IMS is initialized, and
the DFSDCxxx PROCLIB member keyword VACBOPN=INIT,
then the IMS VTAM ACB is opened. If DFSDCxxx PROCLIB member
keyword VACBOPN=DELAY, then the IMS VTAM ACB
open is delayed until the /START DC command is processed.
The /START
DC command also tells VTAM to
pass any queued VTAM logon
requests to IMS.