help troubleshooting inconsistencies in back up sizes

[gaw zay]

Hello list,

I'll first describe my set up:

server1 : live server
server2 : backup
server3 : backup of the backup

so the data set is copied in this order
server1->server2->server3

they are not done at the same time so there would be no collisions.

I use this shell script to back up:

for i in a b c d e f g h i j k l m n o p q r s t u v w x y z `seq 0 9`; do
        /usr/local/bin/rsync -a -z -W --delete /mailhome/$i/ user at backup:/mailhome/$i
done

question one would be does this look correct?

now here is the heart of the problem:
on server1 the partition is 121G
on server2 it's 110G
on server3 it's 118G

so I assume I have multiple problems here. I don't see --progress as being
usable in my case since I have such a large amount of files, how can I
debug what the differences are between these 3 body of files that doesn't
involve actually checking them individually? I basically want to be
informed of errors of any kind (io, permissions) as my logging of
stderr/stdout doesn't show anything, which makes me think many the problem
is my command line but it sure looks ok to me. I'm using version 2.6.3 of
rsync btw.

Thank you.

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