Re: [OpenIndiana-discuss] Tape backup
After the embezzlement debacle, and a couple of complete turnovers (except for me) of the IS staff, my (new) boss and I went to a class specifically about backups. They were saying that not only do we need to keep your normal daily, weekly and monthly backups; we should also keep snapshots of our data for years upon years. They were saying we should do this not only for financial data, but for any data, because you might have a disgruntled employee decide to monkey with your data, and it may take years upon years to discover it. While it would most likely be significantly more difficult to restore that old data -- especially if the tampering were done to a database -- at least you would have some opportunity to recover your uncorrupted information. Just food for thought. On Mar 17, 2013, at 4:36 PM, Doug Hughes wrote: > On 3/17/2013 6:23 PM, Reginald Beardsley wrote: >> Tape as an archival medium has significant issues. Reading poorly stored >> tapes is a "one try" proposition w/ no assurance of success. The first high >> volume commercial application for digital tape was seismic data acquisition >> for the oil industry. The oil companies had very detailed cleaning and >> retensioning schedules w/ a large staff to perform them on the tape >> archives. Absent that level of care, reading old tapes is very difficult and >> requires great skill. Old tape is NOT fun to work with. >> >> High capacity tape drives and tapes are not cheap either. Blank LTO tape is >> almost as expensive as SATA disk. A ZFS based remote replicating server >> using triple parity RAIDZ is probably cheaper than tape. For extremely >> large volumes and long archival periods, optical tape is probably the best >> choice. But then you're probably working for the government. >> >> I would strongly urge comparing the cost of a ZFS backup server w/ daily >> snapshots to the cost of conventional tape backup. I think you'll be quite >> surprised at the implications. >> > > reading old disks is a just as significant if not more of an issue, by my > estimation. Try to find a machine that you can do low voltage differential > disks with these days. That was only 15 years ago. what about SMD? The > controllers keep changing over time. Also, after a disk has been in use for a > significant period of time (say years), the lubrication on the platters tends > to evaporate a little bit so that when you leave it off for a long period of > time (days/weeks) it will stick to the heads and the platters. Tape doesn't > have that issue. > > An LTO5 tape is about $30 each, better in quantity. 1.5TB, more depending > upon compression. That's an enterprise quality tape with much longer shelf > life than a cheap deskstar disk if cared for properly. Even the cheap 1TB > disks are $70. That's almost a 3X advantage. There's still a place for tape > for archival, and yes, you do have to care for it properly, just like you > have to care for everything else. But, cared for properly, tape should still > outlive disk. > > But, used it in its proper place. zfs snapshots make a lot of sense for > online backups! > > > > ___ > OpenIndiana-discuss mailing list > OpenIndiana-discuss@openindiana.org > http://openindiana.org/mailman/listinfo/openindiana-discuss > ___ OpenIndiana-discuss mailing list OpenIndiana-discuss@openindiana.org http://openindiana.org/mailman/listinfo/openindiana-discuss
Re: [OpenIndiana-discuss] Tape backup
On 3/17/2013 6:23 PM, Reginald Beardsley wrote: Tape as an archival medium has significant issues. Reading poorly stored tapes is a "one try" proposition w/ no assurance of success. The first high volume commercial application for digital tape was seismic data acquisition for the oil industry. The oil companies had very detailed cleaning and retensioning schedules w/ a large staff to perform them on the tape archives. Absent that level of care, reading old tapes is very difficult and requires great skill. Old tape is NOT fun to work with. High capacity tape drives and tapes are not cheap either. Blank LTO tape is almost as expensive as SATA disk. A ZFS based remote replicating server using triple parity RAIDZ is probably cheaper than tape. For extremely large volumes and long archival periods, optical tape is probably the best choice. But then you're probably working for the government. I would strongly urge comparing the cost of a ZFS backup server w/ daily snapshots to the cost of conventional tape backup. I think you'll be quite surprised at the implications. reading old disks is a just as significant if not more of an issue, by my estimation. Try to find a machine that you can do low voltage differential disks with these days. That was only 15 years ago. what about SMD? The controllers keep changing over time. Also, after a disk has been in use for a significant period of time (say years), the lubrication on the platters tends to evaporate a little bit so that when you leave it off for a long period of time (days/weeks) it will stick to the heads and the platters. Tape doesn't have that issue. An LTO5 tape is about $30 each, better in quantity. 1.5TB, more depending upon compression. That's an enterprise quality tape with much longer shelf life than a cheap deskstar disk if cared for properly. Even the cheap 1TB disks are $70. That's almost a 3X advantage. There's still a place for tape for archival, and yes, you do have to care for it properly, just like you have to care for everything else. But, cared for properly, tape should still outlive disk. But, used it in its proper place. zfs snapshots make a lot of sense for online backups! ___ OpenIndiana-discuss mailing list OpenIndiana-discuss@openindiana.org http://openindiana.org/mailman/listinfo/openindiana-discuss
Re: [OpenIndiana-discuss] Tape backup
Tape as an archival medium has significant issues. Reading poorly stored tapes is a "one try" proposition w/ no assurance of success. The first high volume commercial application for digital tape was seismic data acquisition for the oil industry. The oil companies had very detailed cleaning and retensioning schedules w/ a large staff to perform them on the tape archives. Absent that level of care, reading old tapes is very difficult and requires great skill. Old tape is NOT fun to work with. High capacity tape drives and tapes are not cheap either. Blank LTO tape is almost as expensive as SATA disk. A ZFS based remote replicating server using triple parity RAIDZ is probably cheaper than tape. For extremely large volumes and long archival periods, optical tape is probably the best choice. But then you're probably working for the government. I would strongly urge comparing the cost of a ZFS backup server w/ daily snapshots to the cost of conventional tape backup. I think you'll be quite surprised at the implications. Have Fun! Reg ___ OpenIndiana-discuss mailing list OpenIndiana-discuss@openindiana.org http://openindiana.org/mailman/listinfo/openindiana-discuss
Re: [OpenIndiana-discuss] Tape backup
We have several buildings in our monastery that are all connected with fiber. I have a backup server in one of the buildings that is geographically separated enough from the building that houses our server room that it is highly unlikely that any fire or natural disaster that we're ever likely to encounter here in the mountains would ever take out both buildings. We still do tape backups, but this is our primary backup system. It's still on the same LAN, so theoretically, it's still vulnerable to attack that way; but all of the shares are hidden, and if I really wanted to, I could limit access to it through only the servers that back their data up to it. It's a lot handier to restore files from it than it is from tape. It's not a good solution for long term storage, but while you are revising your backup routine, you might want to consider something like this if you are not already doing it. Oh, and as long as you have old tapes, don't forget to hold onto a drive for them that you can install in a system if you ever need to restore data from them. I knew someone who got bit by that once. Ouch! Finally, we had an accounting manager in an organization I once worked for that was embezzling large amounts of money. He caught on to the fact that they were on to him. Since he knew where the backup tapes were, and had access to them, they conveniently disappeared. It made prosecuting him significantly more difficult. They were still able to get him for taking over $300,000 (back in the 1990's), but they never were able to determine just how much he had taken. It was most assuredly *much* more than that. And he was such a "nice" guy, too... And don't forget to safeguard important software install disks and licenses. HTH On Mar 15, 2013, at 3:16 PM, Achim Wolpers wrote: > Hi! > > I considere to backup my data on a tape drive off my OI box. Now I face a > couple of questions: > > 1. Which drive is recommended to work with OI? I'd like to use 800GB tapes > 2. Since I plan to use the tapes for long time backup, is the a way to store > the data with some kind of redundancy (like RAID-Z), so that when parts of > the tape might get corrupted over time, the data can still be restored? > > Thanks, > Achim > ___ > OpenIndiana-discuss mailing list > OpenIndiana-discuss@openindiana.org > http://openindiana.org/mailman/listinfo/openindiana-discuss > ___ OpenIndiana-discuss mailing list OpenIndiana-discuss@openindiana.org http://openindiana.org/mailman/listinfo/openindiana-discuss
Re: [OpenIndiana-discuss] Tape backup
On 2013-03-15 22:16, Achim Wolpers wrote: Hi! I considere to backup my data on a tape drive off my OI box. Now I face a couple of questions: 1. Which drive is recommended to work with OI? I'd like to use 800GB tapes 2. Since I plan to use the tapes for long time backup, is the a way to store the data with some kind of redundancy (like RAID-Z), so that when parts of the tape might get corrupted over time, the data can still be restored? I've read that NDMP was provided in OpenSolaris and is an "open" protocol to handle backups in an interoperable manner. Possibly it can wrap ZFS backups even if they need to be split over many tapes. I have no experience with it and haven't read more, so can't really elaborate or even say if it is what might help you. Cursory googling came up with a couple of interesting articles: http://www.oracle.com/technetwork/articles/systems-hardware-architecture/ndmp-whitepaper-192164.pdf http://dtrace.org/blogs/eschrock/2012/02/28/data-replication-building-a-better-ndmp/ HTH, //Jim ___ OpenIndiana-discuss mailing list OpenIndiana-discuss@openindiana.org http://openindiana.org/mailman/listinfo/openindiana-discuss
Re: [OpenIndiana-discuss] Tape backup
We used to use DDS DAT tapes, and with the advent of ZFS we decided that this is really not the best idea. We store spinning rust (aka Hard disks) in a water-proof fire-proof safe which is reckoned to survive > 2 hours in a fire. we offline a disk from an active mirrored pool, physically remove it, then "replace" it with a fresh disk, storing the physical in the safe. The cost per Megabyte, the access speed, and the reliability of this system, for us at least, made significant sense. Especially with the use of snapshots and instant access; We won't go back to tape, not under any circumstances. Jon PS. we have experience of extracting information from tape over 12 years old ... You'll also need to be aware that zfs send doesn't understand end-of-tape ... you'll need to use cpio or similar. On 15 March 2013 21:16, Achim Wolpers wrote: > Hi! > > I considere to backup my data on a tape drive off my OI box. Now I face a > couple of questions: > > 1. Which drive is recommended to work with OI? I'd like to use 800GB tapes > 2. Since I plan to use the tapes for long time backup, is the a way to store > the data with some kind of redundancy (like RAID-Z), so that when parts of > the tape might get corrupted over time, the data can still be restored? > > Thanks, > Achim > ___ > OpenIndiana-discuss mailing list > OpenIndiana-discuss@openindiana.org > http://openindiana.org/mailman/listinfo/openindiana-discuss ___ OpenIndiana-discuss mailing list OpenIndiana-discuss@openindiana.org http://openindiana.org/mailman/listinfo/openindiana-discuss
[OpenIndiana-discuss] Tape backup
Hi! I considere to backup my data on a tape drive off my OI box. Now I face a couple of questions: 1. Which drive is recommended to work with OI? I'd like to use 800GB tapes 2. Since I plan to use the tapes for long time backup, is the a way to store the data with some kind of redundancy (like RAID-Z), so that when parts of the tape might get corrupted over time, the data can still be restored? Thanks, Achim ___ OpenIndiana-discuss mailing list OpenIndiana-discuss@openindiana.org http://openindiana.org/mailman/listinfo/openindiana-discuss
