Depending on the kind of backup interrupt you encountered, the old secondary storage system might be usable again as the tertiary storage system or you might need to assign a new system.
After adding the tertiary system, systemA has a SnapVault backup to systemC and systemC has a SnapMirror backup to system B (or systemD if systemB cannot be reused).
To add the old storage system as the tertiary, complete the following steps.