iSCSI Linux (Centos 5.4)

[RichIbizaSport]

Hi guys, I'll admit I'm not too experienced with Linux but I'm giving it a shot.

The bigger picture is that I'm writing a bash script to shutdown and copy virtual machines overnight to a central scsi array (raid 5).

Anyway, I'm having slight issues setting up iSCSI

I'm testing on 3 machines, all with centos 5.4

(1)Server
(2)Desktop
(3)Desktop

I have a Dell server in our server room with a powervault (raid 5) connected via scsi. I formatted the disk as ext3.

This is then mounted in /iSCSI , this can be seen and writen to on (1). I then installed iSCSI with yum. Got it setup and running.

On (2) and (3) I have the iSCSI initiator setup, they can connect to the target (1) fine

They see the disk with
fdisk -l
but I get: Disk /dev/sdb doesn't contain a valid partition table.

I can format it from each machine. But I need to share this resource, not wipe it everytime I add a machine.

When I've formatted it from (2) I can write to it, but the files won't appear on (3) or the target (1)

Am I missing something blatently obvious?

Thanks

 

[FirebarUK]

Don't mount it from the target (server). If you've mounted it you've already created a filesystem presumably. It could be that you're getting issues with concurrent access to the ext3 filesystem. Perhaps consider presenting each desktop with their own partition to avoid future issues.

 

[memyselfandi]

I would have thought that for the setup you describe, with multiple concurrent access to the same filesystem, your better bet would be to use NFS.

 

[stockhausen]

Use Samba?

I can't say that I know much about iSCSI but as with the response above, why use iSCSI rather than Samba?

 

[FirebarUK]

Sounds like a learning experience, hence iSCSI. As said though, NFS would work well also.

 

[RichIbizaSport]

All very valid points. To be honest it is more an experiement than anything else. But the eventual goal is still to backup some of our infrastructure servers (vms) over night.

But thinking about it, it does seem rather a waste of time. What is the actual purpose of iSCSI? I guess there are some kind of scsi enclosures which connect directly to the network with no operating system as such? Presumably replacing the need for expensive fibre channels.

Can't believe I didn't realise there would be no advantage to using this over smb (in this situation).

Oh well, it was fun . Thanks guys.