[j45degrees]

I have a situation where there are 30 Macs, mostly running OS9 on a variety of G3s and 4s. Currently everyone puts critical files on a small server for nightly back up and only two machines accounting for about 120 GB get a total back up every night using Retrospect.

The move to OSX will likely be over the next 24 months. The total disk space of all the machines is around 550 GB. I'd love to get a server that would back up all the machines then archive from the serve. Is a total back up doable on a nightly basis? What makes the most sense for a situation like this these days?

[Deal]

I can only guess what the end result will be on your network. But here is my situation.

I have a 500mhz G4 server running ASIP. Retrospect backs up to an AIT-2 library that holds four 50/100 cartridges. I use between 4 and 5 tapes per set. It backs up 3 servers including itself.

About half of the data is local the rest is backed up over ethernet (100). When it appends data it gets done by morning. When starting a new storage set it is often still running well into the next day.

I would say, with that amount of data over a network you should maybe implement more than one system to backup that data. On client systems you can backup just their data folder and let them know that's all that's getting backed up.

Shortly I will be going to an Xserve with their recommended 15cartridge library. If things change dramatically I will repost.

[utidjian]

Do the math... lets simplify it: 550GB from a single machine to another machine... that is about 5500GigaBits of network traffic... so over a Gigabit/second network that would take approximately 5500 seconds or 5500/3600 = 1.5 hours (approx). Now, on the surface this seems doable. BUT, in reality, you don't get full Gigabit capacity... your client machines are probably 100Mbit/s at best... so it will take at least 15 hours... this would be network traffic, flat out, for 15 hours under ideal conditions. In reality it would take even longer.

Next is the problem of the backup system. Most good quality single drive tape libraries will do about 10MBytes/second... cheaper ones about 1-3MBytes/sec. So to write 550GBytes to tape will take about about 100 seconds per Gigabyte of data then 55,000 seconds to write the entire 550GBytes of data that translates to 15.3 hours approximately of the tape drive working flat out... Hardly a workable solution.

What most people do when they have 30 clients is create a standard disk image for each type of client. Basically just drag and drop a cpy of Macintosh HD to the network drive on the server. You shouldn't have more than perhaps 4 or 5 of these images. Total disk space shoulr be between 10 and 50G depending on how many apps are installed.

Then all you have to do is worry about backing up the users data.

[j45degrees]

Originally posted by utidjian:
What most people do when they have 30 clients is create a standard disk image for each type of client. Basically just drag and drop a cpy of Macintosh HD to the network drive on the server. You shouldn't have more than perhaps 4 or 5 of these images. Total disk space shoulr be between 10 and 50G depending on how many apps are installed.

Then all you have to do is worry about backing up the users data.

Makes sense to me. Thanks to both of you for the feedback. It's much appreciated.

[geekstud]

Originally posted by utidjian:
What most people do when they have 30 clients is create a standard disk image for each type of client. Basically just drag and drop a cpy of Macintosh HD to the network drive on the server. You shouldn't have more than perhaps 4 or 5 of these images. Total disk space shoulr be between 10 and 50G depending on how many apps are installed.

Then all you have to do is worry about backing up the users data.

If you locate all user data on a central file server already, you'll reduce the network traffic to zero for backups if the backup system is on that file server. Keeping user data on local systems is generally a poor approach to data management for a workgroup.

I just finished a project for a client that involved using two Apple G4 server systems. The primary file server is configured with a Promise Technology 320 GB (available) RAID 0+1 external disk array (8 x 80 GB ATA drives, each on a separate ATA channel, SCSI interface to host). The backup setup server is configured with another Promise 768 GB (available) RAID 5 external array (8 x 120 GB ATA drives, same hardware as above). The backup server (which will be located in a different part of the facility) runs Retrospect server, connecting to the primary file server running a Retrospect client, and uses the RAID 5 array to store multiple "warm" rotating filesystem-based backup sets. Separate "cold" backups to 120 GB Firewire hard disks will be rotated to offsite storage. Tape is so... old. ;-)

Cheers,

-Nathan