Linux – Replacing a Hard Disk with a clone fails

As the owner of professional data recovery firm the proper way to rebuild a broken RAID like this would be to create clones or images of each drive. Never work with the originals. Once you have images of the drives you would need to recreate the RAID in some kind of software like X-Ways. Be sure to keep the correct order of the drives! It can be quite complicated rebuilding RAID ARRAYS, and if the data is important you should label the drives and send them out to a reputable company, but most RAID recoveries are not cheap.

A volume group can have multiple physical disks (or in your case, partitions).

First you need to have space on your larger disk (/dev/sda).

You did not mention that in your post, but based on your question, I would assume that you can make space and then add a new partition that we shall call: /dev/sdaX

EXTENSION AFTER UPDATE:

You can make space on your /dev/sda with simply merging the volume groups, but you don't want to do that - as you stated in your original post. What you need to do is actually more simple than that.

Follow these steps:

Step -5: reduce your physical volume on /dev/sda5 to make space for a new partition:

pvresize /dev/sda5 -L 1500G

Step -4: Use parted to reduce the size of /dev/sda5 to 1600G (yes, a little bit bigger than we used in pvresize!)

Step -3: Use parted to create a new partition, /dev/sda6, with the new available space (it will be around 400G).

Step -2: Check if the kernel could automatically detect the partition change. See if /proc/partition matches the new state (thus, /dev/sda6 is visible). If not, you need to reboot. (Probably it will.)

Step -1: You can make /dev/sda5 to be as big as it can again:

 pvresize /dev/sda5

Step 0: Format /dev/sda6 to a physical volume:

pvcreate /dev/sda6

From this point, /dev/sda6 is our /dev/sdaX.

EXTENSION END

First: you should give /dev/sdaX to the volume group tiffany-vg:

vgextend tiffany-vg /dev/sdaX

Second: you should move all of your data between the (already) two physical volumes of the volume group tiffany-vg:

pvmove tiffany-vg /dev/sdb3 /dev/sdaX

Third: you should remove /dev/sdb3 from the tiffany-vg volume group:

vgreduce tiffany-vg /dev/sdb3

NOTE: The second step above will be a little bit critical, be curious. If it is a root partition, better to do that from a rescue disc. Good luck!

IF YOU SIMPLY MERGED THE VOLUME GROUPS

Step 1: You can simply merge the xen-vg into your tiffany-vg:

vgmerge tiffany-vg xen-vg

Step 2: Move all of your data from /dev/sdb3 to /dev/sda5:

pvmove tiffany-vg /dev/sdb3 /dev/sda5

Step 3: Remove /dev/sdb3 from your new, big volume group:

vgreduce tiffany-vg /dev/sdb3

But beware: here your old, xen-vg volume group ended his life, and all of its volumes are moved below /dev/tiffany-vg. You need to change every reference to them in the system configs ( it is unlikely you needed to change anything out of /etc/fstab).

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