h1. BackupsResearch

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h2. Doing the backup of partitions or other block devices

h3. adb shell cat pipe

"Old versions of the EFS backup instructions":https://redmine.replicant.us/projects/replicant/wiki/BackupTheEFS/17 used the following command:
<pre>
adb shell "cat /dev/block/platform/*/by-name/EFS > /EFS.img"
</pre>

At some point or under some condition, this stopped working and the backup were corrupted.

h3. adb shell cat adb pull

<pre>
adb shell "cat /dev/block/platform/*/by-name/EFS /dev/block/platform/*/by-name/EFS" > /EFS.img" EFS.img
adb pull /EFS.img ./
</pre> 

Doing in in two stage like that seem to be widely used in other instructions (like the ones found in XDA forums).

Normally cat should produce a valid backup, however it might be better to use dd for extra safety.

On Replicant 6.0 0004, the recoveries for the following devices have 'dd':
* Galaxy Nexus
* Galaxy SIII

h3. adb pull the block device

The following should also work:
<pre>
adb pull /dev/block/mmcblk0p3 ./EFS.img
</pre>

The advantage is that it can also backup huge partitions like the user data partition or Replicant system partition.

h3. Also see

* This backup app might be a good option for Replicant 9 or 10: https://github.com/stevesoltys/backup