[Discuss] How do you backup "/" with rsync?

[Steven Kurylo]

> I have read recently that primary master and slave are concepts that are
> only relevant to PATA drives.  So for the pure SATA case (which applies for
> me) the default order of drive assignments seems even more problematic.

It will still scan that controller in the same order.  So usually
those sata ports are listed as 1-4, so linux will call them sd[a-d] if
they're all full.  If linux scans that controller first, the first
disk it finds will be sda.


> irwin at raven> ls -l /dev/disk/by-id/
> total 0
> lrwxrwxrwx 1 root root  9 2007-12-09 21:21 ata-ST3500630AS-9QG3XJPX-part1 ->
> ../../sdb1

You can just use /dev/disk/by-id/ata-ST3500630AS-9QG3XJPX-part1 in
your fstab, instead of /dev/sdb1.  udev guaranties this id to be
unique.  http://www.reactivated.net/writing_udev_rules.html#builtin

For example in my fstab I have

/dev/disk/by-id/usb-Apple_iPod_000A270010E07863 /media/ipod

So that my ipod always gets mounted in the same place.  You don't
actually have to write your own udev rules in this case.

> Is there a better source of internal information I can use to get the model
> and serial numbers of the two drives? If serial numbers are unavailable or
> cannot be used by udev to distinguish disks, then udev might be able to use
> the different controllers (ich9 SATA controller versus jmicron eSATA
> controller) to distinguish the two disks.

You use udevinfo to find out what information is available to udev
when identifying drives:
http://www.reactivated.net/writing_udev_rules.html#udevinfo

-- 
Steven Kurylo