Resolving disk space issues for backup with LVM2

When I look to assisting clients with their near line and off-site backups, I used to come across the issue of "disk creep". This is where a disk gets full, so another disk (USB or Network Attached Storage) is purchased. Eventually you have a succession of 4 or more backup disks with no real backup.

So the approach I have started taking is to use the previous 4 disks as a backup for the new bigger disk.




The idea is that disk capacities have grown and grown because of the adoption of spintronics, we are now able to have 1TB, 2TB - 4TB disks - many times more than 7 years previously.

In this example we have a new 2TB drive, 2 x 500GB Sata drives, a 300GB PATA IDE and a 500GB Pata IDE


Here are the steps I take.

1. copy all data to new drive.
2. verify data using beyond compare
3. in this case make a joined up disk using the old disks ~1.8TB which should be enough to backup the new drive

Joining the "old" disks using LVM

Firstly I use the smallest drive to install a 6GB partition for Lubuntu 64 - a lightweight linux ditribution.
I then leave 2GB for swap and format the rest as a primary partition as ext4 (292GB)

I do this on the 300GB PATA then I format the other disks (500GB) as ext4.

My aim is to create a volume called /buv/buv1 which will be 1.8TB

buv stands for Back Up Volume - you can call it something different if you want.

I open a terminal on the Lubuntu Machine (Ctrl-Alt-T)

Second thoughts - perhaps I should have put the OS on one of the SATA drives then I could have duplicated the OS in case of failure of one device.

Making my dvd-ram writable in Debian

Firstly

apt-get install dvd+rw-tools udftools

Then I knew my dvdram drive was /dev/sr0

Then I formatted - not sure if I needed to do this

# format dvd-ram (optional)
dvd+rw-format -force=full -ssa=default /dev/sr0

then I issued

mkudffs /media/cdrom


However mine was /dev/sr0

Then I mounted

mount /dev/sr0

then I mount as per

mount /mnt/dvdram

http://www.panticz.de/node/355
http://mandrivausers.org/index.php?/topic/45839-mounting-and-formatting-dvd-ram/