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I’m a little confused by this submission. CASTOR is the old system that has since been replaced by the CERN Tape Array since ~2020: https://cta.web.cern.ch/cta/

This is mentioned on the page but it’s easy to miss.

For the current status of tape storage at CERN see: https://indico.cern.ch/event/1471803/contributions/6967379/a...

For reference, most disk storage for physics data uses an in-house solution called EOS: https://eos-web.web.cern.ch/eos-web/

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Does tape array replace castor? Just from the names it sounds like tape array is the actual storage, and castor is an abstraction that automatically decides what's kept on disk and what's kept on tape

The abstraction isn’t really a thing any more. It was a nice idea but in practice it’s an operational nightmare not knowing if data is available and for how long it will be. For reference staging can take days during intense activity and you don’t want to loose performance randomly seeking around and switching between tapes.

The linked page seems to think it does.

"As of June 29th 2020, CTA, the CERN Tape Archive, started to be operated as the successor of CASTOR and gradually replaced it."

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