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We backup 1.5 PB of data per month to tape; What alternative solution would you suggest given 'cloud' in all its guises is too expensive?
by 6LLvveMx2koXfwn 3y ago
We backup 1.5 PB of data per month to tape; What alternative solution would you suggest given 'cloud' in all its guises is too expensive?
- jonatron 3y agoHow much is 1.5PB of tapes, and 1.5PB of hard drives?
- jpc0 3y agoI would hazard a guess that storing tapes takes up significantly less physical space than hard drives. I don't think hard drive based storage and tape bases storage have quite the same use case.
- dagw 3y agoI would hazard a guess that storing tapes takes up significantly less physical space than hard drives. An 18TB tape is basically the same size as an 18TB 3.5" hard drive.
- adrian_b 3y agoI doubt that this can be true. I am using older LTO-7 cartridges, with a raw capacity of 6 TB. The newer LTO cartridges must be compatible mechanically with the old cartridges, because the same drive must be able to read and write them. The LTO cartridges are smaller than 3.5" drives, they have maybe about 2/3 of the volume of a 3.5" HDD. Moreover, a tape cartridge is many times lighter than a HDD. I have suitcases with 20 tape cartridges that are as convenient to carry as any typical suitcase. A luggage carrying 20 HDDs would have a very noticeable weight, and its volume would be great not only due to the bigger HDDs, but it would require serious padding to avoid HDD destruction if the case were dropped accidentally.
- dagw 3y agoOK, you made me do the math. LTO tapes are 225 cm^3 and 3.5" HDDs are 245 cm^3 so I stand corrected. The weight point is a really good one as well as a HDD is 3 times the weight of a tape.
- dagw 3y agoTapes are roughly 3 times cheaper pr. TB than hard drives.
- wongarsu 3y agoAbout $8000 of LTO-9 tape, $21000 of Toshiba MG10 hard drives, $38000 of Seagate IronWolf Pro NAS hard drives.
- throw0101a 3y ago18TB(raw) LTO-9 tapes go for US$ 105: * https://tapeandmedia.com/lto-ultrium-9-tapes/ https://tapeandmedia.com/lto-ultrium-9-tapes/ If your data is compressible then you can of course store more. The drives themselves use Streaming Lossless Data Compression, but of course you can send them things like gzip, JPEG, MPEG files which are already compressed; SLDC: * https://www.ecma-international.org/wp-content/uploads/ECMA-321_1st_edition_june_2001.pdf https://www.ecma-international.org/wp-content/uploads/ECMA-3... LTO-10 is supposed to have 36TB raw and is estimated for perhaps 2024.
- comboy 3y agoI'm surprised HDD don't turn out to be less expensive option calculating in all infrastructure + man hours. Do you have a ballpark what's percentage cost difference for your use case?
- rtkwe 3y agoAt the PB scale you start running robotic tape machines that eliminate much of the human labor involved.
- londons_explore 3y agoWorth noting that many uses for hard drives are IO limited. Ie. you're running a database and keep a few hundred GB of hot records in RAM, tens of TB of medium records on SSD, and a few PB of rarely accessed records on hard drives. However, even those rarely accessed records often have more accesses per year than the hard drives can support - so you are forced to buy 400 drives instead of 200 drives and keep each half full. End result: There is a lot of 'almost free' space on the hard drives, as long as you are happy to only read/write the data very rarely.
- rtkwe 3y agoIf you're having such an IO bottleneck that you're doubling your HDD array to provide the necessary throughput how do you actually run backups or restores using those disks? Do you hope you only need it in off hours?