Good morning,
We are experiencing an issue with our Commvault environment related to copying data to tape, and I am hoping someone can help explain the behavior or suggest a fix.
Currently, our Commvault system is configured to take weekly FULL backups of all file shares and VMs every Thursday. Once these full backups complete, they automatically copy to tape. This process itself works as expected.
The problem is the volume of data being written to tape.
Each week, I have to manually update the Copy Policy “From Date” to the Monday of the current week to ensure that only the most recent data is copied. If I forget to do this, the amount of data copied to tape increases significantly.
For example:
January 2026
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Week 1: I set the copy date to Monday 5th January. On Thursday, approximately 100 TB is written to tape (usually completing by the following Wednesday).
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Week 2: I forget to update the date. On Thursday, it again attempts to copy around 100 TB.
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Week 3: I forget to update the date again. At this point, the tape copy never completes and appears to be copying Week 2 + Week 3 data, effectively doubling the amount.
If I cancel the tape copy and still don’t reset the date to the current Monday, the amount of data continues to grow exponentially. When we first noticed this issue, Commvault was attempting to copy 1.6 PB to tape, which far exceeds our available tape capacity.
What I don’t understand is why the system behaves this way. I would expect it to simply copy the latest completed weekly full backup, rather than re-copying older data repeatedly.
This configuration was originally set up by a third-party support company, and although they have investigated it, we’ve never been able to resolve the issue. As a workaround, we are forced to manually adjust the copy date every week, which is obviously not ideal.
Could someone please advise why this is happening, or suggest a better configuration to prevent older data from being repeatedly copied to tape? I can provide screenshots and any additional information if required.
Commvault version: 11.36.80
Thanks in advance.
