NEWBIE - Fibre question

[nate2345]

Hi Guys,

We're looking into fibre for our backup. We don't expect to go over 1 TB of data over the next 5 years. Therefore we don't think we need a SAN. However we would like todo full backups every night. Is there any reason not to go with a fibre switch and backup to an old computer (dell gx100) and put a fibre card and 2 400 GB hard drives?

Currently the largest server to backup is 20GB every night, which takes 4 hours for tape backup. There will be about 5 servers to backup.

Thanks for your help,
Nate

 

[comtec17]

You do not need a SAN, especially on old hardware. I state this because using old hardware will limit your backup speed due to the slowest part of the system. You should concentrate on changing your backup methods (from full nightly) to doing differentials or incrementals. This will 1. Save you money on tapes, 2. Reduce your backup window, and 3. Allow you more time to correct an issue shall it arise.

I think you are confused on the concepts of a SAN as you mention placing a Fibre Switch ($5000), an HBA (single attached, no redundancy, and $1200), and 2 x 400GB drives in an old workstation (not supported and you are backing up to disk via ATA, where is the Fibre disk or tape?).

A BAN (Backup Area Network) is used to offload a public LAN from backup traffic.

I think you may be wanting to put in a secondary LAN switch, a second NIC, and some ATA disk (not recommended, especially to an old workstation as it will be as slow as the slowest part of that machine which is usually the PCI bus). In this case you are creating a backup LAN, not SAN.

Last note, backup to disk is supposed to be used as a staging effort, not a permanent home for the data as the shelf life and meantime of tape is much longer than disk as well as more durable.

I hope this helps, if I misunderstood our question, please let me know.

 

[nate2345]

Thanks for your response.

What I was thinking was (tell me where/if I'm wrong):

Put a fiber card on the server to be backed up (serverA). Put a fiber card on an old computer (serverB) and place a fibre switch in between them. Connect serverA via fibre cable to the switch, and have a fibre link from the switch going to serverB. ServerB (the backup server) will have 1 or 2 400 gb drives. And back up in this way.

What's wrong with that scenario?

Nate

 

[Chacalinc]

What's wrong with that scenario?

your ServerB [red]IS NOT A NAS[/red]!! it doesn't work as you think. You could use that topology *only* if you are using IP over FC. Instead to spend a lot of money in a solution that doesn't work buy a Gigabit ethernet switch and a couple of Gigabit ethernet cards and make a *private LAN*.

Cheers.

Chacal, Inc.

 

[nate2345]

I thought that fibre works with ipaddresses to communicate? Is there a good site that would give me a good understanding of how fibre works and is implemented - I don't want to keep bothering you with these questions - unless you're ok with that.

Thanks
Nate

 

[Chacalinc]

I thought that fibre works with ipaddresses to communicate?

Nope.. Fibre Channel runs [blue]SCSI commands on Fibre Channel Protocol[/blue]

Google for SAN, FC, Fibre Channel, FC protocol, etc. wikipedia!

We are glad to help you, but read something or google first.

Chacal, Inc.

 

[p5wizard]

Don't want to confuse you more, but there ARE implementations of TCPIP on top of FCP as well (mostly vendor specific I guess).

But Chacal is right: for SAN - the protocol is SCSI3 (SCSI on top of FC)


HTH,

p5wizard