Fix confirmed; I see in Katello 4.6 (I am at 4.6.2) the backup now works and does not fail on re-enabling the sync plan. Yay!
Starting the following service(s):
redis, postgresql, pulpcore-api, pulpcore-content, pulpcore-worker@1.service, pulpcore-worker@2.service, pulpcore-worker@3.service, pulpcore-worker@4.service, pulpcore-worker@5.service, p-worker@6.service, pulpcore-worker@7.service, pulpcore-worker@8.service, tomcat, dynflow-sidekiq@orchestrator, foreman, httpd, puppetserver, dynflow-sidekiq@worker-1, dynflow-sidekiq@works-queue-1, foreman-proxy
\ All services started [OK]
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re-enable sync plans:
- Total 1 sync plans are now enabled. [OK]
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Remove maintenance mode table/chain from nftables/iptables: [OK]
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Compress backup data to save space:
/ Compressing backup of Postgres DB [OK]
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Done with backup: 2023-02-07 14:15:46 -0600
**** BACKUP Complete, contents can be found in: /backups/katello-backup-2023-02-07-13-57-55 ****