This information was accessible using simple query commands from IBM service branch office terminals.
The 2915 was a small keyboard-display driven by a large electronic controller and data interchange unit, the IBM 2948.
The cost of this display system, with its large controller, prevented the 2915 terminals from being used in branch offices, so they were used in regional support centers instead.
The older RETAIN system continued to be used for several years afterwards, running in parallel with RETAIN/370, still connected to branch-office terminals.
In the mid-1970s, a RETAIN was expanded to permit multiple copies of the database to be hosted on geographically distributed systems.
RETAIN's custom-built Data Bank Manager, which served as the foundation for all RETAIN applications, and the IRIS search engine, was modified to support "mirroring" of file updates to take place automatically across the network, in a manner nearly invisible to the application programs, but which providing a high level of data integrity.
Most applications were developed by IBM programmers in Raleigh, NC, (moved to Boulder, Colorado, in 1976) with some work being done in North Harbour, UK.
The hardware diagnostic programs were written to allow control via a remote connection to applications on the RETAIN system that could be controlled by IBM specialists located at the IBM support center in Chicago, managed by Paul Rushton, and also including the original plant of manufacture of the CPU.