Suggestions for backup design
I've got to implement overnight backups for 31 Macs, 5 iBooks and 3 PCs, across a 10MBit LAN on a weekly basis (approximately 22.5 GB storage transferred a night) What am I going to need in the way of server capabilities (I'd like a Mac for security reasons), and will thin ethernet carry this sort of transfer reliably? Does anyone have a recommendation for the sort of storage device for this much stuff? Help! Rich -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
Re: Suggestions for backup design
on 11/17/00 4:51 AM, Rich Grenyer at [EMAIL PROTECTED] wrote: I've got to implement overnight backups for 31 Macs, 5 iBooks and 3 PCs, across a 10MBit LAN on a weekly basis (approximately 22.5 GB storage transferred a night) What am I going to need in the way of server capabilities (I'd like a Mac for security reasons), and will thin ethernet carry this sort of transfer reliably? Does anyone have a recommendation for the sort of storage device for this much stuff? Ethernet will carry the transfer reliably. At optimal speeds, it would take about seven hours to back up 22.5Gb over a 10Mbit line, and that does not include Retrospect's preparation and comparison routines. A more reasonable timespan would probably be more like 15-20 hours, depending on your hardware and overall network utilization. So, you really have to decide *when* to backup rather than *what* or *if* to backup. If all of the computers are unused and running over the weekend, you could do a full (or recycle) backup over the weekend and normal backups each night of the week. Otherwise, you could split your clients into seven groups and each night do a full backup of one group and partials of the rest. For a 10Mbit LAN, just about any PowerPC Mac, preferably PCI, will be plenty of horsepower; just be sure to get a backup device that will hold at least a week's worth of data on one tape/disk. I recommend the Ecrix VXA drive, but there are several good cost-vs.-capacity comparisons in the list archives, so you can make your own call there. Jon L. Gardner '89, Computer Systems Manager mailto:[EMAIL PROTECTED] Texas AM University Dept. of Food Services http://food.tamu.edu/ Tel 979.458.1839 * Fax 979.845.2157 * Hip 979.229.4323 PGP public key available at http://food.tamu.edu/pgp/jon.html "Republicans may be 'the stupid party,' but at least the average conservative gun-nut can put a nice clean shot through the correct hole on his ballot from 200 yards." (Columnist Mark Steyn, London Daily Telegraph, 10/12/2000) -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
Re: Suggestions for backup design
I agree with Mr. Gardner on this as well. Something else to consider though is that 22.5MB is the total you have now, but when you do incrementals onto the same media, that total can get much higher depending on the data that changes. For example, I have a user that edits photo's that are between 200MB and 900MB in size. If I backup the 900MB file on Monday night, she changes it on Tuesday, Retrospect will then back it up again on Tuesday night. And no, it does not erase the previous version. I've had users that upgraded their systems (Win98 to Win2k recently) that when Retrospect goes out there to back it up, the whole thing looks new. Just a warning. I've learned to deal with it, but me having to "deal with it" vs just letting it go is just a matter of having more backup capacity. I'd recommend getting at least double of what you really need, but bigger is better. I used to backup 40 Macs over LocalTalk. It took 2 weeks of nightly backup to complete a single Level 0 (L0=Full/new backup) backup on all systems. We then went to 10BaseT (hub) and it cut it down to 3 days for L0. We then went to 10/100 switches where about 1/3 of the machines were 100Mbit and the rest still at 10Mbit and it cut the time down to about 1 night + 1 hour. Our backups run from 6pm to 6am, so that would be 13 hours. Now we have a mostly 100Mbit network, but the number of machines being backed up has grown to 120. It takes about 14 hours still, but there is a lot more data out there now. A bit of history...when I was backing up over LocalTalk, the largest hard disk we had in any Mac was 500MB. Now 500MB won't even hold most of the System Folders! Largest single drive right now in our Macs is 50GB I believe. We have two backup systems. One is Windows NT running Retrospect and using a DLT autoloader. The other is a Mac with a DLT 20/40 on it backing up 11 machines, all of them are on switched 100BaseT. on 11/17/00 4:51 AM, Rich Grenyer at [EMAIL PROTECTED] wrote: I've got to implement overnight backups for 31 Macs, 5 iBooks and 3 PCs, across a 10MBit LAN on a weekly basis (approximately 22.5 GB storage transferred a night) What am I going to need in the way of server capabilities (I'd like a Mac for security reasons), and will thin ethernet carry this sort of transfer reliably? Does anyone have a recommendation for the sort of storage device for this much stuff? Ethernet will carry the transfer reliably. At optimal speeds, it would take about seven hours to back up 22.5Gb over a 10Mbit line, and that does not include Retrospect's preparation and comparison routines. A more reasonable timespan would probably be more like 15-20 hours, depending on your hardware and overall network utilization. -- -- To subscribe:[EMAIL PROTECTED] To unsubscribe: [EMAIL PROTECTED] Archives:http://list.working-dogs.com/lists/retro-talk/ For urgent issues, please contact Dantz technical support directly at [EMAIL PROTECTED] or 925.253.3050.
