What is the recommended GUI configuration to set up a fisheye backup schedule that retains the most recent backup only? Specifically, what value should I store in the backup file date pattern field for Fisheye
I'm sorry but this is not possible. As informed by the https://confluence.atlassian.com/display/FISHEYE/Backing+up+and+restoring+FishEye+datadocument, "Be aware that scheduled back ups can fill up disks unless you regularly move or delete old archives", so this needs to be managed outside the application.
There's a feature request for this you can see at https://jira.atlassian.com/browse/CRUC-6498but it is marked as "Won't fix", as it was preferred to leave the backup management to the customers to ensure thatFishEye doesn't get in a state where critical backups have been erased.