Abstract: A computer complex is provided with a mechanism for message delivery and redelivery in a controlled manner through the use of distributed shared memory. This provides a mechanism for overall computer system complex operation from a plurality of consoles which are registered or identified to the system and which particularly enhances capabilities for remote operation. In this way the complex can be made to look like a single system. Direct communication between any pair of systems is provided, say, by channel-to-channel adapters. Message information is maintained in each system which can also communicate with shared storage to establish update level information regarding locally maintained message information.