Topic: dar2 backups and drives changing

[icemannz]

Hi all,
I am hoping some guru from here can give me an answer to this interesting issue.
I have a SME 7 box newly created with 2 sata drives inside it.
They are in a mirror and working well

I also have a removable drive caddy plugged in.
It has a sata cable connecting it to the motherboard that doesn't change.
I setup the Dar2backup system and initially it worked ok.

Then the users will swap out the drive caddy for another one.
Drive is identical make size etc...
The issue is that the drive assignment changes,
on one drive it will be sdc and then when they change the drive it will be sdd, so the backup will fail.

I don't understand how this happens because it uses the same sata cable and as far as i understand, the Dar2backup system only mounts the drive when it is doing a backup.
So if they swap out the drive caddy and change it for anohter one, how do I stop the drive assignment changing from sdc to sdd.

Any help is appreciated.

[piran]

Any help is appreciated.

...guessing but might be similar to:
http://wiki.contribs.org/USBDisks

[icemannz]

Hi all, I have tried what was suggested in the paper on USB drives but it won't work for Dar2Backup because it will only try the first entry in the FSTAB file. So if I have more than one drive mouning using a label command, then it will find the first entry that points to the mount point and try to mount that drive.
If the drive is the first one it will work but if it is one of the others it won't work.

So I have a drive caddy which allows you to pull out the drive while the machine is running and swap the caddy for the next one.
But what I am finding is that some drives come up as sdc and some come up with sdd.
So when the backup runs it will only find the first entry in fstab and if that drive is connected it will work but not for the others.

I can't imagine that others are not having this issues.
I also can't see how the machine is showing one drive as sdc and the other as sdd as they cannot be both connected at the same time, the drives are all the same and they connect using the same sata connector.

Any more ideas

[piran]

Any more ideas

Get your wallet out and speak to the developers.
AFAIK 'hot swap' functionality isn't supported...

[icemannz]

Ok then,
How do others backup there SME Servers, surely the easiest way is to use external esata or usb drives.
If Dar2Backup doesn't support removable drives being changed, how do we best perform these types of backups ?

[piran]

I can't help you. You do it your way. Bye.

[janet]

icemannz

Firstly hot swapping of drives is not supported by the underlying operating system/kernel. It has nothing to do with the features of the backup contrib eg dar2. You will have to wait until upstream sources ie CentOS  fully incorporate that functionality and sme server uses that version of CentOS. I haven't looked to see if CentOS 5.x, and therefore if sme 8.x, supports hot swap.
Even if you use a hot swap caddie the concept won't work, as the underlying OS does not support that piece of hardware.

....surely the easiest way is to use external esata or usb drives.

Nothing wrong with eSATA drives, but you will have to power down the server when you swap a drive.

The only viable option is to use external USB drives, which you can add or remove on a powered up sme server.

If Dar2Backup doesn't support removable drives being changed, how do we best perform these types of backups ?

All the popular backup contribs as well as the default sme backup, can backup to a connected USB drive. See the backup category in the Contribs section linked from the Wiki main page, note there is a Wiki link at top of these forums.

Your question really seems to be how do I hot swap eSATA drives, sorry you cannot, not yet at least.

If you must use your hot swap caddies etc, you might consider backing up to a workstation that has an OS and hardware that supports hot swap drives, and then run backups using the backup to workstation option from the server manager.

[shawnbishop]

Hi

I sue 4 x 2TB USB drives for my backups, I have installed the USB Contrib that allows me to identify the USB drives by the UUID number, when they are plugged in they get mounted to a drive automatically..

Only problem I have had with it that it mounts them read only.

Shawn