butc actually uses a signed int32 so the tape capacity could be doubled to 4TB fairly easily (I have misplaced the patch somewhere but I could find it). That isn't quite 6.25TB but your compression ratio seems "optimistic" so it might be enough until the next generation of LTO.
https://lists.openafs.org/pipermail/openafs-info/2013-May/039580.html On Mon, 2015-05-18 at 13:26 -0400, Jeffrey Altman wrote: > Russ, > > All of the backup protocol messages are limited to sizes that max out at > 2TB (2^32 1KB blocks). > > I am not aware of anyone that is actively maintaining the backup suite > shipped with OpenAFS. > > I recommend that the University of Pittsburgh communicate with its > commercial support provider to request an estimate for designing, > implementing, and testing the necessary changes. Changes to the backup > suite protocols do not require submission through a standardization > process (unlike other AFS3 RPC suites). > > Jeffrey Altman > > > > > On 5/18/2015 12:48 PM, Howard Jr, Russell A wrote: > > Over the summer, we are upgrading our tape library from LTO-4 to LTO-6 > > and would like to take advantage of the full capacity of the new tapes. > > > > > > > > The tapeconfig documentation indicates that the max tape size supported > > is 2TB. Is this still the case? > > > > > > > > Our current drive is LTO-4 with a native uncompressed capacity of 800 GB > > and a compressed capacity of 1.6TB. For our current backups, we > > specified the tape capacity in the tapeconfig file as 1600G. This has > > allowed us to utilize the full capacity of the LTO-4 tapes. Our new > > tape drive will have a native uncompressed capacity of 2.5TB and a > > compressed capacity of 6.25TB. > > > > > > > > If the 2TB limit is still in place, we would like to request that it be > > increased to at least 6.25TB (or larger to support future tape capacity > > increases). Once our new tape drive arrives, we are willing to test any > > patches to help facilitate an increase in the tape size limit. > > > > > > > > -- > > > > Russ Howard > > > > Systems/Programmer III > > > > Computer Science Department > > > > University of Pittsburgh > > > > 6209 Sennott Square > > > > 412-624-8834 > > > > > > > _______________________________________________ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
