verifying two zfs filesystem hierarchies

[Nikos Vassiliadis]

Hi,

I would like to verify that my pool is correctly stored on a disk
and haven't found a way to do so. I believe I can assume that
it is OK since all snapshot names appear identical to the original
pool. I was looking for something like "zfs send -R blah | sha256"
and "zfs send -R USBDISKCOPY/blah | sha256" but this doesn't work
for obvious reasons. Is there a tool that could do such a thing?

My two candidates are:
1) zpool scrub USBDISKCOPY (will verify the pool).
2) zfs send -R USBDISKCOPY/blah (will send the filesystem hierarchy
     effectively reading and verifying everything.

Since scrubbing is slower than sending I think of using "zfs send".

Thoughts? Any other ways?

Thanks in advance!
Nikos