instead, you should have used parted(8) or similar to expand the
partition, then used resize2fs(8) to expand the file system on this
partition to its new size.


So I'm trying parted on a new, clean volume created from the snapshot, attached to /dev/sdm  As I explained before, I can't do

$ parted /dev/sdm

[root@domU-12-31-39-0E-B2-61 ~]# parted /dev/sdm
Error: Error initialising SCSI device /dev/sdm - Invalid argument


I CAN do parted on the path:

$ parted /dev/sdm1
GNU Parted 1.8.1
Using /dev/sdm1
Welcome to GNU Parted! Type 'help' to view a list of commands.

But then i get this error:

(parted) resize 1 0 500GB
Error: The location 500GB is outside of the device /dev/sdo1.

Which is course is true ...

(parted) print                         
                                  
Disk /dev/sdm1: 21.5GB
Sector size (logical/physical): 512B/512B
Partition Table: loop

Number  Start   End     Size    File system  Flags
 1      0.00kB  21.5GB  21.5GB  ext3    


So I'm not sure where to go from here...

thanks!
Dan