Backup boot SD card ( without unused space )

 bash

    
$ fdisk -l
Disk /dev/sda: 29.72 GiB .....
....
Device
/dev/sda1 ...
/dev/sda1 ...


  

So I first tried:

 bash

    
$ dd bs=4M if=/dev/sda conv=fsync status=progress | gzip > /path/path/foobar.gz


  

But this create a huge .gz file ! because it backup the unused space too :'(

If you know a ~simple command to just backup the used space I'm all ears.

I've discovered rpi-clone

Seem really great, too bad the github tab discussion has been not activated :/ and If the documentation is not clear enough, no way to ask the community.

EDIT: Actually it seem that it clone a SD to a full dest drive ! so not as destination file correct ??

in the README you can read:

rpi-clone-setup is for setting the hostname in /etc/hostname and /etc/hosts files.

It is run automatically by rpi-clone if -s args are given, but before your first clone using a -s option, test run rpi-clone-setup with:

rpi-clone-setup -t testhostname

So what is the purpose of the -s argument ? If you want to set another hostname into the destination backup ? why can we set fews ? Can we have few hostname for a same machine ???

and the -t argument is not even documented (if I'm not mistaken ..)

• Did you ever tried rpi-clone ?
• what's your 2cent about it ?
• does rpi-clone sda promt you to confirm the destination ?
• do know some thing else ?
• is it possible to output the backup as a file ?