I am trying to expand the size of a xen disk. I found instructions on a google search, but they don't seem to be complete. I first logged into the physical server, and expanded the .img file that the virtual server is using. I then log into the virtual server and use fdisk to resize the partition, using all of the available space. The instructions then tell me to "add this disk to another xen guest so that you have a non mounted filesystem disk available. You cannot execute these commands from within the xen guest you are trying to expand." Once I have done this, it tells me to fdisk -l to locate the disk, and use resize2fs to resize the disk. There are no instructions on how to add the disk to another xen guest, and I am not quite sure what I am trying to do there.

If I try to resize2fs it gives me a disk in use error. I think I need to access the partition from another xen OS and then run the resize2fs command. Any idea how I would do that?

I figured out that I need to go into the physical server and add the disk to a different xen server, and select the correct .img file as the new disk. At that point, I can see the "partition" with fdisk, but when I try to resize2fs, I get a "bad magic number in superblock" error.

I discovered that the filesystem was linux LVM, so I changed it to that, but I am still getting a bad superblock error, I also tried alternate superblocks 8193, 16..., etc and no dice.