5 ms·

We stopped using tape just because datasets are too large. Fulls and differentials are not feasible at petascale. With LTO7 - a petabyte takes over a month to b

We stopped using tape just because datasets are too large. Fulls and differentials are not feasible at petascale. With LTO7 - a petabyte takes over a month to backup with a single drive. You need 50 or so to pull it in a day, assuming your storage can do 15GB/sec sustained.

fjsolwmv 9y ago
50 is not a large number. What's the problem?
- conception 9y ago
  50 tape backup drives is not a large number for less than a single rack of storage? Buy one rack of storage and two racks of tape backup for it? That seems... not great. Even outside of managing hundreds and hundreds of tapes.
- fencepost 9y ago
  I think he means that you'd need 50 tape drives with the backup running simultaneously across all of them to run the backup in a day - fortunately that's not how backups get run, you generally aren't running full backups every time, you run a full then do incremental or differential backups starting from that point with periodic full backups. The point I caught from the article that most people are bypassing is that tape provides a fully disconnected and unreachable (by attackers) backup, where many online backup systems are using software and systems that may be reachable from the systems being backed up. In the worst case of a motivated knowledgeable skilled attacker that could mean an attacker having the ability to wipe backups as well as live systems.
  - conception 9y ago
    This is a good point. It really depends on so many factors what a good solution is for one's dataset.
hmschreck 9y ago
What do you use instead?
- conception 9y ago
  We have fulls in the cloud - and the initial seed took forever but we have a big pipe that made it feasible. And then do file system diffs, checksumed with an index file. An object store would probably be a better solution for those without a giant pipe. With an aggressive HSM policy of moving data to it. But there are so many factors in terms of what sort of data you have and what you're doing with it, change rate etc. Our data is very WORSE (write once and read seldom if ever). So use tends to die off pretty quickly after 6 months or so which allows us to keep most data on near-line indefinitely.
  - rsync 9y ago
    "We have fulls in the cloud - and the initial seed took forever but we have a big pipe that made it feasible." We (rsync.net) now have multiple customers that have allocated 1+ PB of storage and are using our 10gb connections[1] for the initial sync. It's 1.2[2] cents per GB, per month but it's fully online, live, browseable storage - not a nearline/offline solution like glacier/nearline. We'd be happy to serve you ... [1] We use Hurricane Electric (he.net) for our connectivity in Denver, Fremont and Hong Kong. [2] and dropping ...
    - conception 9y ago
      Hey Rsync Folks, We've actually looked at you but we are a non-profit and something like Oracle being $0.001/GB offsets the offlineyness of it because costs rule for us. But, love your service and recommend it to those that have a better fit than us.
    - sliken 9y ago
      1.2 cents per GB per month sounds great. Unfortunately http://rsync.net/pricing.html http://rsync.net/pricing.html cheapest rate is 4 center per GB per month, and that's only for over 10TB.
linksnapzz 9y ago
People can and do use tape-backed archivers for multipetabyte datasets-I'm one of them. HPSS was pretty mach made for this, although it is not a "backup software" in the same way as Networker, commvault, bacula etc. http://www.hpss-collaboration.org/ http://www.hpss-collaboration.org/
- conception 9y ago
  Yeah, I think there is still a play for LTFS and using tape for datasets, but for classic backup at scale? Seems untenable.

fjsolwmv 9y ago

50 is not a large number. What's the problem?

conception 9y ago
50 tape backup drives is not a large number for less than a single rack of storage? Buy one rack of storage and two racks of tape backup for it? That seems... not great. Even outside of managing hundreds and hundreds of tapes.
fencepost 9y ago
I think he means that you'd need 50 tape drives with the backup running simultaneously across all of them to run the backup in a day - fortunately that's not how backups get run, you generally aren't running full backups every time, you run a full then do incremental or differential backups starting from that point with periodic full backups. The point I caught from the article that most people are bypassing is that tape provides a fully disconnected and unreachable (by attackers) backup, where many online backup systems are using software and systems that may be reachable from the systems being backed up. In the worst case of a motivated knowledgeable skilled attacker that could mean an attacker having the ability to wipe backups as well as live systems.
- conception 9y ago
  This is a good point. It really depends on so many factors what a good solution is for one's dataset.

hmschreck 9y ago

What do you use instead?

conception 9y ago
We have fulls in the cloud - and the initial seed took forever but we have a big pipe that made it feasible. And then do file system diffs, checksumed with an index file. An object store would probably be a better solution for those without a giant pipe. With an aggressive HSM policy of moving data to it. But there are so many factors in terms of what sort of data you have and what you're doing with it, change rate etc. Our data is very WORSE (write once and read seldom if ever). So use tends to die off pretty quickly after 6 months or so which allows us to keep most data on near-line indefinitely.
- rsync 9y ago
  "We have fulls in the cloud - and the initial seed took forever but we have a big pipe that made it feasible." We (rsync.net) now have multiple customers that have allocated 1+ PB of storage and are using our 10gb connections[1] for the initial sync. It's 1.2[2] cents per GB, per month but it's fully online, live, browseable storage - not a nearline/offline solution like glacier/nearline. We'd be happy to serve you ... [1] We use Hurricane Electric (he.net) for our connectivity in Denver, Fremont and Hong Kong. [2] and dropping ...
  - conception 9y ago
    Hey Rsync Folks, We've actually looked at you but we are a non-profit and something like Oracle being $0.001/GB offsets the offlineyness of it because costs rule for us. But, love your service and recommend it to those that have a better fit than us.
  - sliken 9y ago
    1.2 cents per GB per month sounds great. Unfortunately http://rsync.net/pricing.html http://rsync.net/pricing.html cheapest rate is 4 center per GB per month, and that's only for over 10TB.

linksnapzz 9y ago

People can and do use tape-backed archivers for multipetabyte datasets-I'm one of them. HPSS was pretty mach made for this, although it is not a "backup software" in the same way as Networker, commvault, bacula etc. http://www.hpss-collaboration.org/ http://www.hpss-collaboration.org/

conception 9y ago
Yeah, I think there is still a play for LTFS and using tape for datasets, but for classic backup at scale? Seems untenable.