It looks like there is already a solution for this https://github.com/woblerr/pgbackrest_exporter we can try to use

Hi @Lalit Choudhary

Thank you for the report and feedback.

Yes, anyone can add any additional metrics through TextFileCollector from any script.. we did the same in GAS team, we had our own backup solution and that was creating Textfiles for PMM to read.. and we had alerts based on those..

They are trying to use some external backups script ? Or they are using a backup solution what we provided?

Per the original request from the customer (what I’m reading from SN), it was more about “monitoring their Backup Tool “ and warning when there are some errors happening.
The user is using pgbackrest and wants to know when there will be an error from it.

Theoretically, it can be some additional TextFileCollector approach to expose errors and scrape them to PMM.

@Tibor Korocz (Percona) , @Charly Batista JFYI