Database table physical_library

What is the purpose of the physical_library table? How do we populate it? Where is it used? I see the logical_library table has a column for the physical_library_id. cta-admin ll ls does not mention physical library.

Dear Jeff,
Looks like you installed cta 4/5.10.0-1 and performed the schema upgrade to schema version 14.0.
This schema introduces new tables and new columns, from the new schema but as the third number indicates it: this is a pivot version.
Pivot versions do not use any of the new columns to be backward compatible with the previous schema: Tagging a new CTA release - EOSCTA Docs

You can see in the release notes that this option was added in v4/5.10.1-1 : ReleaseNotes.md · main · cta / CTA · GitLab

We should spend some time to review the upgrade path and how the new features of 4/5.10.x should be enabled.

Thank you for your feedback.

Hi Jeff,

To answer your question: the purpose of the physical_library table is to record the number of slots in each physical tape library. The logical libraries tell us how many tapes we have, but don’t tell us what our physical library occupancy is or how many slots we have free. It will be possible to associate logical libraries with a physical library which will allow us to monitor library occupancy.

This feature is for the purpose of long-term library monitoring and capacity planning. It has no effect on day-to-day operations. If you leave this table unpopulated, everything will continue to work.

The table is populated with the new cta-admin physicallibrary command (it is separate from logicallibrary which you mention above). We have not yet started using the feature in production but it will come later this year.

Cheers,

Michael

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