no free space error for tape backups
We use 6.25TB capacity tapes, but when the AMS states that the tapes have around 2TB of occupied space, we start to get "no free space" errors; our only solution so far has been to move the tapes to the FREE pool and back; this morning we actually are using a tape that only shows 1.265TB of occupied space;
Is 6.25 Tb uncompressed capacity or some 'advertised' with compression? Acronis use its own compression and native capacity values are used.
Here is a statement by HP: "C7976A HP LTO 6, LTO6, LTO-6, Ultrium 6 tapes can hold up to 2.5TB of native or uncompressed capacity with up to 6.25TB of compressed data". We have Normal selected for the compression level in the Backup options of 11.5 Advanced. The tape we inserted this morning was sitting at 1.265TB of occupied space per AMS. The backup that threw-up this "no free space" error would have consumed only 615MB as it was a differential. The stats at the top of the Tape Vault archive history screen shows an overall compression ratio of 1:1.5
Yes, it doesn't look normal even for 2.5 TB of native capacity. I can only suggest to update to the latest update (4) which includes many tape-related fixes, but it may as well not help.
We do have the current version. There was one setting that I changed which may be the culprit. We have the Acronis pool set to move the tapes to the Rewritable pool once they full. In the Rewritable pool, we had the box checked to move the tapes back to the Acronis pool when full. I unchecked that option and will know the results of this change this Friday. Perhaps the tapes didn't get recognized in the Rewritable pool correctly with that option checked. I will update this post on Friday with the results. Thanks.
The setting change described above did not solve the issue. I have an active support request with Acronis now. I will update this post with new details once they are received from Acronis Support. Thanks.
This topic can be closed as we are in a "wait and see" mode with Acronis Support on this issue. We are waiting to see what happens when a tape gets closer to the 2TB occupied space threshold that has triggered this issue recently. Thanks.