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LTO-9 tapes can be easily found on Amazon in many countries, made by IBM, HP, Quantum or Fuji. The vendor does not matter, whichever happens to be cheaper at t

LTO-9 tapes can be easily found on Amazon in many countries, made by IBM, HP, Quantum or Fuji. The vendor does not matter, whichever happens to be cheaper at the moment is fine. For the tape drives, the internal drives can be cheaper by around 10%, but I prefer the tabletop drives, because they are less prone to accumulate dust, especially if you switch them on only when doing a backup or a retrieval. The tape drives have usually very noisy fans, because they are expected to be used in isolated server rooms. I believe that the cheapest tape drives from a reputable manufacturer are those from Quantum. I have been using a Quantum LTO-7 tape drive for about 7 or 8 years and I have been content with it. Looking now at the prices, it should be possible to find a tabletop LTO-9 drive for no more than $5000. Unfortunately, the prices for tape drives have been increasing. When I have bought an LTO-7 tabletop drive many years ago it was only slightly more than $3000. The tapes are much cheaper and much more reliable than hard disks, but because of the very expensive tape drive you need to store a few hundred TB to begin to save money over hard disks. You should normally make at least two copies of any tape that is intended for long-term archiving (to be stored in different places), which will shorten the time until reaching the threshold of breaking even with HDDs. Even if there are applications that simulate the existence of a file system on a tape, which can be used even by a naive user to just copy files on a tape, like copying files between disks, they are quite slow and inefficient in comparison to just using raw tape commands with the traditional UNIX utility "mt". It is possible to write some very simple scripts that use "mt" and which allow the appending of a number of files to a tape or the reading of a number of consecutive files from a tape, starting from the nth file since the beginning of a tape. So if you are using only raw "mt" commands, you can identify the archived files only by their ordinal number since the beginning of the tape. This is enough for me, because I prepare the files for backup by copying them in some directory, making an index of that directory, then compressing it and encrypting it. I send to the tape only encrypted and compressed archive files, so I disable the internal compression of the tape drive, which would be useless. I store the information about the content of the archives stored on tapes (which includes all relevant file metadata for each file contained in the compressed archives, including file name, path name, file length, modification time, a hash of the file content) in a database. Whenever I need archived data, I search the database, to determine that it can be found, for instance in tape 63, file 102. Then I can insert the corresponding cartridge in the drive and I give the command to retrieve file 102. I consider much better the utility "mt" of FreeBSD than that of Linux. The Linux magnetic drive utilities have seen little maintenance for many years. Because of that, when I make backups or retrievals they go to a server that runs FreeBSD, on which the SAS HBA card is installed. When a tabletop drive is used, the SAS HBA card must have external SAS connectors, to allow the use of an appropriate cable. I actually reboot that server into FreeBSD for doing backups or retrievals, which is easy because I boot it from Ethernet with PXE, so I can select remotely what OS to be booted. One could also use a FreeBSD VM on a Linux server, with pass-through of the SAS HBA card, but I have not tried to do this. My servers are connected with 10 Gb/s Ethernet links, which does not differ much from the SAS speed, so they do not slow much the backup/retrieval speed. I transfer the archive files with rsync over ssh. On slow computers and internal networks one can use rsync without ssh. I give the commands for the tape drive from the computer that is backed up, as one line commands executed remotely by ssh. The archive that is transferred is stored in a RAMdisk before being written on the tape, to ensure that the tape is written at the maximum speed. I write to the tape archive files that have usually a size of up to about 60 GB (I split any files bigger than that; e.g. there are BluRay movies of up to 100 GB). The server has a memory of 128 GB, so I can configure on it a RAMDdisk of up to 80 GB without problems. This method can be used even with a slow 1 Gb/s or 2.5 Gb/s network, but then uploading a file through Ethernet would take much more time than writing or reading the tape. There is one weird feature of the raw "mt" commands, which is poorly documented, so it took me some time to discover it, during which I have wasted some tape space. When you append files to a partially written tape, you first give a command to go to the end of the written part of the tape. However, you must not start writing, because the head is not positioned correctly. You must go 2 file marks backwards, then 1 file mark forwards. Only then is the head positioned correctly and you can write the next archived file. Otherwise there would be 1 empty file intercalated at each point where you have finished appending a number of files and then you have rewound the tape and then you have appended again other files at the end.

netrap 2y ago
Only Sony or Fuji actually make tapes. The rest are rebranded.
- adrian_b 2y ago
  True, but the rebranded tapes are frequently cheaper than Fuji or Sony.
alchemist1e9 2y ago
A lot very interesting details in your reply - thanks. I have this question: If you aren’t budget constrained today and had to set it all up again. What would you do? While I’m a Linux guy, I’ll happily run BSDs when appropriate, like for pfSense, and if it really has better mt tools or driver for LTO-9 drives due to the culture/contributors being more old school, then I’d just grab a 1U server to dedicate for it run a BSD and attach the drive to that. You seem to have extensive practical hands on experience and while I was doing tapes 20 years ago this will be first time I’m hands on again with it since then. So I need to research most reliable drive vendors and state of kernel drivers and tools, just as you are alluding to. Pretend you have $50K if needed (doubt it). 2PB existing data, 1PB/year targeted rate, probably 10-20%/year acceleration on that rate. with a data center rack location, 20Gb/s interconnect via bonded 10Gb NICs to storage servers (45drives storinators) and then an office center cabinet/rack/desk (your choice) and will put a tape drive holding at least 8 tapes in data center, planning for worst case of 100TB a month and data center visits to swap in new tapes shouldn’t be too frequent. Any details on what you would do would be interesting.
- adrian_b 2y ago
  Like I have said, it is not necessary to dedicate a full-time FreeBSD server for this, you can use either a Linux server that is rebooted temporarily in FreeBSD or a FreeBSD virtual machine on the Linux server. Around $5000 to $6000 should be enough for a LTO-9 tabletop tape drive plus a suitable SAS HBA card and SAS cable. The card must have matching SAS connectors and SAS speed with the tape drive. More money will not bring anything extra until a much higher amount is reached, which would be enough to buy a tape autoloader/library, which would eliminate the necessity for a human to insert and remove the cartridges into the tape drive when needed. I am not sure if $50K is enough for a tape autoloader. Tape autoloaders/libraries are worthwhile only for very big organizations where the amount of data that is continuously written or read to or from the tapes is very large. For a small business or for an individual a tape autoloader is certainly not worthwhile, because the tape drive will be in use at most a small fraction of every day. 1 PB/year is less than 3 TB/day. This can be written on a single tape in a little more than 2 hours. Even with a simple non-pipelined implementation of the file uploading with the writing on the tape, the backup can be done in less than 4 hours. Even writing 2 copies can be done in less than 8 hours. The backup can be done mostly or completely overnight. For a much bigger amount of data one could buy several tape drives, before starting to think about an autoloader. Also it is possible to pipeline the network transfers with the tape writing, for a backup speed higher by around 50%. If money would not be a problem and if the data needs to be archived for a long term, so that multiple copies are desirable, I would buy 2 tape drives, to be able to write 2 copies simultaneously. This would also halve the time for archiving the initial 2 PB of existing data, which will take several months, so a speed-up would be desirable. Having 2 drives will also increase the reliability, as the system will continue to work if one becomes defective. With only 3 TB written per day, a LTO-9 tape, which has a capacity of 18 TB, will be enough for 6 days. So unless a backup must be restored, the operator would need to change the tape only once per week. This is a moderate amount of data, easy to handle with a single drive, even if two are preferable for redundancy and for higher speed. I do not understand your reference to a "a tape drive holding at least 8 tapes in data center". If you mean an autoloader, from what you describe it does not seem that the very big expense for an autoloader would be justified. The LTO tapes are best stored in suitcases that can contain 20 cartridges, i.e. when using LTO-9 that is 360 TB. Therefore 3 suitcases store more than 1 PB, i.e. a year of data according to your example. The suitcases should be stored in a secure safe or cabinet. They are usually made to be stackable. I have assumed that your 1 PB is of already compressed data. If the data is compressible than the requirements for the usage time of the drives and for the storage volume would be much smaller. I have forgotten to mention that after I compress and encrypt the archived files, I add redundancy with a Reed-Solomon code, e.g. with the par2 program. If I choose e.g. a redundancy of 5%, then a file retrieved from the magnetic tape could have defects of up to 5% of its size, while the original data could still be extracted from it.

netrap 2y ago

Only Sony or Fuji actually make tapes. The rest are rebranded.

adrian_b 2y ago
True, but the rebranded tapes are frequently cheaper than Fuji or Sony.

alchemist1e9 2y ago

A lot very interesting details in your reply - thanks. I have this question: If you aren’t budget constrained today and had to set it all up again. What would you do? While I’m a Linux guy, I’ll happily run BSDs when appropriate, like for pfSense, and if it really has better mt tools or driver for LTO-9 drives due to the culture/contributors being more old school, then I’d just grab a 1U server to dedicate for it run a BSD and attach the drive to that. You seem to have extensive practical hands on experience and while I was doing tapes 20 years ago this will be first time I’m hands on again with it since then. So I need to research most reliable drive vendors and state of kernel drivers and tools, just as you are alluding to. Pretend you have $50K if needed (doubt it). 2PB existing data, 1PB/year targeted rate, probably 10-20%/year acceleration on that rate. with a data center rack location, 20Gb/s interconnect via bonded 10Gb NICs to storage servers (45drives storinators) and then an office center cabinet/rack/desk (your choice) and will put a tape drive holding at least 8 tapes in data center, planning for worst case of 100TB a month and data center visits to swap in new tapes shouldn’t be too frequent. Any details on what you would do would be interesting.

adrian_b 2y ago
Like I have said, it is not necessary to dedicate a full-time FreeBSD server for this, you can use either a Linux server that is rebooted temporarily in FreeBSD or a FreeBSD virtual machine on the Linux server. Around $5000 to $6000 should be enough for a LTO-9 tabletop tape drive plus a suitable SAS HBA card and SAS cable. The card must have matching SAS connectors and SAS speed with the tape drive. More money will not bring anything extra until a much higher amount is reached, which would be enough to buy a tape autoloader/library, which would eliminate the necessity for a human to insert and remove the cartridges into the tape drive when needed. I am not sure if $50K is enough for a tape autoloader. Tape autoloaders/libraries are worthwhile only for very big organizations where the amount of data that is continuously written or read to or from the tapes is very large. For a small business or for an individual a tape autoloader is certainly not worthwhile, because the tape drive will be in use at most a small fraction of every day. 1 PB/year is less than 3 TB/day. This can be written on a single tape in a little more than 2 hours. Even with a simple non-pipelined implementation of the file uploading with the writing on the tape, the backup can be done in less than 4 hours. Even writing 2 copies can be done in less than 8 hours. The backup can be done mostly or completely overnight. For a much bigger amount of data one could buy several tape drives, before starting to think about an autoloader. Also it is possible to pipeline the network transfers with the tape writing, for a backup speed higher by around 50%. If money would not be a problem and if the data needs to be archived for a long term, so that multiple copies are desirable, I would buy 2 tape drives, to be able to write 2 copies simultaneously. This would also halve the time for archiving the initial 2 PB of existing data, which will take several months, so a speed-up would be desirable. Having 2 drives will also increase the reliability, as the system will continue to work if one becomes defective. With only 3 TB written per day, a LTO-9 tape, which has a capacity of 18 TB, will be enough for 6 days. So unless a backup must be restored, the operator would need to change the tape only once per week. This is a moderate amount of data, easy to handle with a single drive, even if two are preferable for redundancy and for higher speed. I do not understand your reference to a "a tape drive holding at least 8 tapes in data center". If you mean an autoloader, from what you describe it does not seem that the very big expense for an autoloader would be justified. The LTO tapes are best stored in suitcases that can contain 20 cartridges, i.e. when using LTO-9 that is 360 TB. Therefore 3 suitcases store more than 1 PB, i.e. a year of data according to your example. The suitcases should be stored in a secure safe or cabinet. They are usually made to be stackable. I have assumed that your 1 PB is of already compressed data. If the data is compressible than the requirements for the usage time of the drives and for the storage volume would be much smaller. I have forgotten to mention that after I compress and encrypt the archived files, I add redundancy with a Reed-Solomon code, e.g. with the par2 program. If I choose e.g. a redundancy of 5%, then a file retrieved from the magnetic tape could have defects of up to 5% of its size, while the original data could still be extracted from it.