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bhattisatish | 3 months ago
I have two NAS servers (both based on Synalogy). But I need something where I can back it up and forgot about it till I want to restore the stuff. I am looking at a workflow of say, weekly backup to tape. Update the index. Whenever I want to restore a directory or file, I search the index, find the tape and load the same for retrieval.
NAS can be used for continuous backup (aka timemachine and timeshift). And archival at a weekly level.
mm0lqf|3 months ago
I've got a HP StorageWorks Ultrium 3000 drive (It's LTO-5 format) connected to one (LSI SAS SAS9300-4i), in my NAS/file server (HP Z420 workstation chassis). Don't go lower than LTO-5 as you will want LTFS support.
About £150 all in for the card and drive (including SFF-8643 to SFF-8482 cables etc..) on EBay
Tapes are 1.5TB uncompressed, and about £10/each on Ebay, you'll also want to pick up a cleaning cartridge.
I use this and RDX (1TB cartridges are 2-4 times the price, but drives are a lot cheaper, and SATA/USB3, and you can use them like a disk) for offline backup of stuff at home.
embedding-shape|3 months ago
However, is there no open formats? The whole LTO ecosystem of course reeks of enterprise, and I'd expect by now at least one hardware hacker had picked together some off-the-shelf components to build something that is magnitude cheaper to acquire, maintain and upgrade.
progbits|3 months ago
At least with drives you can run regular health checks a corruption scans. Tape is good for large scale but you must have automation that keeps checking the tapes.
adrian_b|3 months ago
However, there is little need to check the tapes, because the likelihood of them developing defects during storage is far less than for HDDs.
Much more important than checking the tapes from time to time is to make multiple copies, i.e. to use at least duplicate tapes that are stored in different places.
Periodic reading is strictly necessary only for SSDs, and it is useful for HDDs, because in both cases their controllers will relocate any corrupted blocks. For tapes it is much less useful. There is more risk to damage the tape during an unnecessary reading, e.g. if the mechanism of the tape drive happens to become defective at exactly that moment, than for the tape to become defective during storage.
The LTO cartridges are quite robust and they are guaranteed for 30 years of storage after you write some data on them.
In the past there have existed badly designed tape cartridges, e.g. the quarter-inch cartridges, where the tape itself did not become defective during storage, but certain parts of the cartridge, i.e. a rubber belt, which was necessary to move the tape, disintegrated after several years of storage. Those have disappeared many years ago.
adrian_b|3 months ago
The problem is that while the tapes are at least 3 times cheaper than HDDs, and you have other additional advantages, e.g. much higher sequential reading/writing speed and much longer storage lifetime of the tape, the tape drives are extremely expensive, at a few thousand $, usually above $3k.
You can find tape drives for obsolete standards at a lower price, but that is not recommended, because in the future you may have a big tape collection and after your drive dies you will no longer find any other compatible drive.
Because the tapes are cheap, there will be a threshold in the amount of data that you store where the huge initial cost of the tape drive will be covered by the savings from buying cheap tapes.
That threshold is currently at a few hundred TB of stored data.
I use an LTO tape drive and I have recovered its cost a long time ago, but I have more than 500 TB of data.
However, only a third of that is actual useful data, because I make 2 copies of each tape, which are stored in different locations. I am so paranoid because it is data that I intend to keep forever and I have destroyed all the other supports on which it was stored, e.g. the books that I have scanned, for lack of storage space. An important purpose of the digitization has been to reduce the need for storage space, besides reducing the access time.
I keep on my PC a database with the content of all tapes, i.e. with all the relevant metadata of all the files that are contained inside the archive files stored on the tapes.
When I need something, I search the database which will give me the location of the desired files as something like "tape 47 file 89" (where "file 89" is a big archive file, typically with a size of many tens of GB). I insert the appropriate tape in the drive and I have a script that will retrieve and expand the corresponding archive file. The access time to a file averages around 1 minute, but then the sequential copying speed is many times higher than with a HDD. Therefore, for something like retrieving a big movie, the tape may be faster overall than a HDD, despite its slow access time.
There are programs that simulate a file system over the tape, allowing you to use your standard file manager to copy or move files between a tape and your SSD. However I do not use such applications, because they reduce a lot the performance that can be achieved by the tape drive. I handle frequently large amounts of data, i.e. the archive files in which I store data on the tapes are typically around 50 GB, so the reduced performance would not be acceptable.
doe88|3 months ago