Resize backing store

[Jeff Brown]

Apologies in advance if this be a stupid question, as everything I've 
read seems to suggest it's impossible.

Slowly running out of space on a 200GB root partition.

Is it possible to create a snapshot - leaving the QCOW2 image 
'quiescent' - resize it using 'qemu-img resize' - then pivot the 
snapshot back? (Then shutdown, attach the storage to another bootable 
OS, and run fdisk and resize2fs.)

Everything I've read says to shutdown the VM; but besides the real 
possibility of the snapshot blockcommit being corrupted when pivoted 
into the newly resized backing store, I don't see why it shouldn't work. 
And save some significant downtime.

Please can someone advise if this is actually possible, or if I'm 
wasting my time?

Thanks!

-- 
Jeff Brown
Future Foundation
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