Challenge:  A city government office was running critical property tax workloads on an N-4 mainframe, end-of-service DASD, and an unsupported back-level version of z/OS. The N-4 system was not capable of running supported software. There was no disaster recovery (DR) strategy other than an on-premises SAN-based VTS copy of their data. Their newly hired CIO realized if the system responsible for managing tax revenue failed, it was career limiting.

Objective: Eliminate risk in the event of a system outage and unsupported hardware and software.

Industry: Government

Solution: PSR Mainframe Hosting


The client had been operating for some time with an unsupported DASD and making in-house repairs with used parts on a DS6800. When PSR became involved, the immediate threat was a failed DASD controller, which put all the data at risk of loss, including critical property tax records.

There was no viable tested DR strategy in place. While the mainframe was under a maintenance agreement, it was oversized, inflating both IBM MLC and maintenance expenses. Longer term, all their software was unsupported and in need of upgrades.


PSR proposed mainframe production hosting and disaster recovery. The PSR team utilized a system capable of running both the client’s current unsupported version of z/OS as well as currently supported versions.

PSR was able to utilize the city’s existing VTS for the migration to PSR’s site, which involved establishing VTS replication to PSR. This quickly eliminated the client’s single-site location risk while also allowing PSR to build a duplicate system for testing.

The hosted system was remotely tested by the client for over 30 days. Once satisfied, the production migration workload was moved to PSR. VTS data replication to PSR’s DR site in Tennessee was established, where a mainframe system is available in the event of a disaster.


The client has been running on a hosted system at PSR for several years. The client’s resiliency was immediately improved, TCO reduced, and software supported. Over time, PSR refreshed the VTS, added DASD capacity, and implemented Global Mirror to further improve RPO and RTO.

PSR also provided systems programming services and assisted the client in upgrading to supported software versions. PSR has maintained a flat hosting fee since 2018, and the client recently renewed their hosting agreement for an additional three years with PSR.