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My office is currently in the process of reviewing our current backup scheme. We are currently debating on moving to tape for our nightly backup and I'm curious to see the feedback of some of the forum users based on previous experiences. I'll try to be as clear and concise as possible regarding equipment, software, etc. I'll be quick to address any configuration questions that may arise.

 

The current scheme works as follows: five artists' G4/G5s (all running current retro clients under 10.4.6) backup nightly via our network to a concatenated 240GB drive on a G4/450DP (also running 10.4.6 and the current version of retro). This same machine also has an UltraSCSI card with a small raid connected that we use as a file server (only 120GB - the RAID and card were freebies). The nightly backup consists of backing up each artist's Client folder. Retrospect is set to backup to a file and creates a separate snapshot file, matching is set to replace existing files so that each night we only back up new/modified files, compression is turned off (since it would compress via software and is painfully slow). This works fine, until we begin to run out of space and need to recycle the HD. Typically, an artist's Client folder will be between 20-80GB during a typical work week, mulitply that by the five artists and you get an idea of the amount of data we're backing up. We've honestly just started using the G4 and concatenated drive due to some new hardware upgrades, so we've yet to test the limitations of this system - but my boss figured as long as we're switching things up, we might as well look into other options. Prior to last week all the machines were backing up to a 160GB Firewire drive - when we had enough space.

 

Here's the scenario - ideally we'd like to have an alternating tape back up so that one tape can be offsite in the event of fire, tornado, whatever. I've had experience with this type of system in the past where three tapes are used in alternating succession with the previous days tape on site, the day before that is off site, and the third day is in the drive awaiting modified/new files. However, given the amount of data we'll need to store on one tape it's becoming apparent that this may stretch our budget a bit further than we're prepared to go. So far, the only "budget-concious" solution I've found is a Quantum DLT-V4 which supports 160/320 data (non-compressed/compressed). But finding media for it that supports 160/320 (80/160 is the norm) is kind of difficult. Add to that the fact that we'd like to keep perhaps two or three sets of three tapes in rotation and I begin to worry about finding media in the future should our initial media begin to fail. I've also looked into LTO solutions, but those appear to be out of our price range, and perhaps a bit overkill. Previous formats (DAT,etc.), obviously don't provide the amount of storage per tape that we'll need.

 

Keep in mind that the primary purpose will be to provide a nightly back up of working projects on the artist's machine and have an offsite copy of those projects that is no more than two days old. Given those parameters, the solution described above seems to be our best (and most economical) bet. We're currently satisfying need number one with the internal concatenated drive, so I'm wondering if the 2K we looking at investing in the tape solution is worth having that one offsite copy? Are there any options I've overlooked? Are there other solutions that may provide similar results without the added cost of going to tape?

 

Any suggestions, advice or comments from previous experience are greatly appreciated.

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I've got one comment and a recommendation. Comment: We did have a fire about a year ago. Our floor of our office building was condemned, demolished to bare concrete, and rebuilt. We lost all computers but no data because of our offsite backups and Retrospect, and our important documents weren't lost either because of our fire-resistant filing cabinets. I don't know about you, but the cost of the computers is nothing compared to the value of our data. We were back up and running Monday morning in temporary offices after the Friday night fire. We are thankful for Retrospect and offsite backups.

 

Recommendation: You really need an autoloader. It will change your life and make tape swapping automatic. Exabyte has a very nice 1u 10-slot VXA autoloader solution (both firewire and SCSI - we have the SCSI) that is a good choice for small businesses the size of yours and ours. See:

Exabyte VXA products

Exabyte also has LTO solutions and other high-capacity solutions. I have no connection with Exabyte other than being a satisfied user of their product on our server.

 

The older VXA model (still being sold) is their VXA-2 1x10 1u PacketLoader, which has a VXA-2 drive (80/160 with X23 tapes) and a 10-slot autoloader. If you use one slot for a cleaning cartridge, you then have 9 slots for backup tapes, and we are seeing about 110 to 120 GB (compressed) per VXA-2 X23 tape using Retrospect 6.1 Workgroup on our Xserve G5 2.0 GHz SP with ATTO UL4D SCSI card. It's a bit unclear what your nightly backup needs are, your numbers seem to indicate about 400 GB per week or so, which seems to point to 4 or 5 tapes per backup set, so it would seem possible for you to have two backup sets in the autoloader, certainly if you don't reserve a cleaning cartridge slot.

 

The newer model is their VXA-320/172 1x10 1u PacketLoader, which has an interesting marketing approach. It's the same autoloader as for the VXA-2 drive, and the drive in the VXA-320/172 is firmware-updatable to be 320 GB per tape (compressed) (as the VXA-320 drive) or half of that (172 GB compressed - as the VXA-172 drive). So small businesses can buy the VXA-172 model with autoloader and then, as capacity needs increase, pay the firmware upgrade fee and get a double-capacity unit without any equipment changeout. Your capacity needs would certainly be met by the VXA-320, and you would have some capacity headroom as your needs grow.

 

A few people are seeing DOA units from Exabyte, but they are quickly swapped out and replaced. We haven't had any problem, and the Exabyte support has been great. The price for the VXA-2 with autoloader (SCSI) and ethernet remote admin interface is $1725.70 (USD) ($1409.95 SCSI without ethernet remote admin interface) and VXA-320 with autoloader and ethernet remote admin interface is $2299.00 (only available in SCSI with remote admin). The VXA-172 (SCSI, doesn't come with ethernet remote admin) is $1491.55. Only the VXA-2 with autoloader is available as FireWire, not the VXA-320/172. There's also an upgrade kit for the VXA-2 autoloader to replace the drive with a VXA-320. These prices are at MacConnection (which is where we got ours), other people have them too. So such a solution would seem to be around your $2K budget that you state. X23 tapes (80/160/320 GB) are readily available from MacConnection and are about $64 each. The same tapes are used in the VXA-2 and VXA-320/172 drives. We have found the remote ethernet admin interface to be useful when trying to figure out just what the heck Retrospect was doing when we had some wierdness, but it's not necessary in daily use.

 

A concern I would have, though, is that you are using a G4 / 450 DP for your backup computer, and that's a bit underpowered to pump data to these high-capacity drives. It maxes out our Xserve G5 2.0 GHz SP with ATTO UL4D SCSI card when Retrospect is doing its backups. So, if you continue using your G4 / 450 DP as the backup computer, you may see less than optimal capacity on the tapes because your server won't be able to pump the data fast enough to get full capacity. At a minimum, you might need a high performance SCSI card (I'd suggest ATTO), so be prepared for that possible budget hit if your capacity seems low.

 

If the Mac Retrospect had D2D2T (we are hopeful that this feature will appear in a future version - it's already there in the Windows Retrospect) then the backup window would be shorter and you wouldn't have as much trouble pumping the data to the tape drive. But that's the future, not now.

 

If you do go the autoloader route, see my comments about barcodes in another thread on these forums:

Barcodes

 

Just my suggestions, good luck, best regards,

 

Russ

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Thanks for the comments - I had considered the autoloader route, but thought it would be too expensive. However, looking at the examples that you provided, it appears to be on par with some of the single tape solutions I've been looking at. We do have an UltraSCSI card in the G4 currently - I'm not sure that would help the speed or not.

 

As far as our nightly back up needs, once the first back up is complete, updating each night should be a breeze for retrospect. Only on extremely busy weeks where several new large projects are started or in progress would there be any substantial update for Retrospect to make. Once the whole client folder is backed up (the whold 20GB or whatever) after that only new and updated files will be added. I'm hoping that one back up set can hold us for two weeks, then bring in another set (again, I'm hoping that each set contains 2-3 tapes, one offsite). After two weeks, the previous set is recycled and the current two weeks goes offsite. Retrospect would only be copying the entire client's folder every other week - in between that it would be incremental updates. I hope this makes sense.

 

I do like the idea of the autoloader though - I'll do some more research and see what I can come up with for the boss. Thanks for autoloader info, you've saved me quite a bit of time on the research end.

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Quote:

We do have an UltraSCSI card in the G4 currently - I'm not sure that would help the speed or not.

 


Yea, I saw that in your configuration in your first post, but noted that it was driving your RAID:

Quote:

This same machine also has an UltraSCSI card with a small raid connected that we use as a file server (only 120GB - the RAID and card were freebies).

 


Two comments/warnings on that:

 

(1) Our Xserve G5 came with Apple's UltraSCSI card (really, a rebranded LSI Logic 22320 Dual-Channel Ultra 320 SCSI). Never worked right with Retrospect, the autoloader would often fail to appear after boot unless I went in and did a manual device scan in Retrospect. Once it appeared, it would work fine until next reboot. We don't reboot the server except for OS updates, but I got tired of having to remember this, replaced the card with an ATTO UL4D, and the problems disappeared.

 

(2) I think that there is something funny when Retrospect has its tape drive on the same SCSI channel as a heavily-used OS disk drive - ours is a SoftRAID RAID 1 mirror (10,000 RPM Seagate Cheetah LVD SCSI) of our OS volume/LUN (a RAID 5 LUN on an Apple Hardware RAID card). We saw Retrospect hang about once a week when it did its initial device scan before doing the first backup. The problems disappeared when we moved the Retrospect tape drives onto their own SCSI channel of the ATTO UL4D. It's my suspicion that Retrospect caused some sort of a reset on the SCSI channel that caused a disk transfer or seek interrupt to get dropped, but it was so hard to reproduce that the precise cause is not known.

 

So, if you've only got a single-channel SCSI card, you may see this issue. Because it's timing related (you have to get the reset at exactly the right (wrong) moment), you may not see it on your G4 / 450 DP.

 

Oh, one other thing. If you run the numbers, and if you are like us and never re-use tapes (when they fill up, they are archived - we need to be able to go back to any snapshot in the past), the VXA-320 pays for itself (over the VXA-2 or VXA-172) in a couple of autoloader fills because of the double density over the VXA-2 / VXA-172 density on the same X23 tapes.

 

Good luck.

 

Russ

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Thanks Russ - I think we're leaning toward the single tape configuration of the VXA-320. Simply becuase we have no room to set up a rack-mount style piece of equipment. And, after evaluating the logs, I'm fairly positive we'll manage to fit each nightly session on a single 320 cartridge. The SCSI card has two external channels and three internal channels (two Ultra, one narrow). Again, space is at a premium - that G4 is packed to the gills inside, otherwise I'd consider an internal VXA-320. I also think we will end up recycling our tapes - we don't have any real need to access data much further back than a few weeks. In fact, there's never been a case in which we needed anything other than the previous days version of a file. On a rare occassion a completed job will get lost - but this is rare, finished projects are moved onto a firewire drive (that also gets backed up) and once a week we burn and catalog DVDs of completed projects. Those completed projects are then removed from the artist's mac. But that's a totally seperate process from our nightly back up. You've been a huge help, I appreciate you taking the time to help us out.

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Quote:

I think we're leaning toward the single tape configuration of the VXA-320. Simply becuase we have no room to set up a rack-mount style piece of equipment.

 


Ok. As you can appreciate, it's a different choice for those of us who already had to go the rack route for our Xserve G5.

 

Don't count on being able to fit 320 GB on an X23 tape, though. As I mentioned, we are seeing about 110 to 120 GB per 160 GB (compressed) X23 tape on VXA-2. I spoke with an Exabyte tech, and he indicated that most people see about 80% capacity improvement (not 100%) with the VXA-320 over the VXA-2 with real-world files, so I'd expect about 200 GB (compressed) on an X23 tape if we moved to VXA-320. For us, the upgrade decision would be made on the cost savings of tape (VXA-320 upgrade would pay for itself in a couple of months).

 

Exabyte does sell some sort of a case with feet for the autoloader unit so you could put it on a table rather than a rack. But it's a big guy, and it's not light. Even though only 1u high, it's standard rack width and about 30 inches deep. Maybe you could put big legs on it and use it as a coffee table.

 

I really can't emphasize strongly enough, though - an autoloader will change your life. No more missed backups because you forgot to swap the tape, etc. They just happen. And, if you are out of town or at home, you can VPN into your firewall, ARD over to your server, fire up Retrospect, and retrieve some file in the autoloader from backup that you just have to have. Been there, done that.

 

Good luck.

 

Russ

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