When a z/OS image fails, Control‑M/Enterprise Manager running on either Unix or Windows NT detects the connection failure to IOAGATE through its keep-alive mechanism, and attempts to reconnect to IOAGATE. When IOAGATE and CTMAS are restarted on a backup image using the DVIPA associated with IOAGATE, Control‑M/Enterprise Manager will successfully reconnect to IOAGATE on the new image.

IOAGATE running in conjunction with the CTMAS can be moved to any z/OS image in a Sysplex without being tied to the z/OS image in which the main Control‑M Monitor is running. This is because CTMAS communicates with Control-M through files such as the Active Jobs file (AJF), IOA Conditions file, and Control‑M Resources file, as well as through Shouts and GRS (the ENQ/DEQ mechanism).

Although multiple IOAGATE instances can be started in parallel anywhere in a Sysplex to support other applications, only one instance of IOAGATE used in conjunction with CTMAS can exist in the Sysplex, using the CTMPLEX facility. For more information on CTMPLEX, see the Control‑M chapter in the INCONTROL for z/OS Administrator Guide.