[Borgbackup] Newbie Questions

[Thomas Waldmann]

> In order to synchronize my home directory on PC1 with home on PC2, I
> plug the external drive into PC2, "borg mount" to /tmp/borg and then use
> rsync from the mounted directory to my real home directory on PC2.

That should be fine if you use rsync correctly for your use case (esp.
using or not using the -a -H --delete options, read the man page).

Be aware that borg mount does not support all metadata, but it might be
good enough for what you need. If you need ACLs, xattrs, bsdflags or fs
specific attributes, borg mount might be not good enough (just try it).

> Since I travel to dangerous places there is also the possibility that
> both laptops and the external drive are stolen.  Before any travelling,
> I plan to use borgbackup with the cloud service rsync.net  If anything
> happens I will buy a new laptop and use the cloud service to restore the
> new laptop.

At least for that repo, I'ld suggest using repokey.

It might be also less problematic for using your usb drive repo from 2
machines.

Of course use a good passphrase, so that when you lose your repo disk,
the thief can not use your repokey.

> 1.  When I set up the borg respository on my external drive I used "$
> borg init --encryption=keyfile  localrepo"  The borg documentation says
> I should back up my key.  However, I just installed borgbackup on PC2
> and was able to read my data without ever being asked for a key, just
> the passphrase.

Then you either used no encryption (none) or repokey or you have the
keyfile on PC2 also.

If that is not the case, file a bug on github, please.

> 2.  I am comfortable with computer science data structures.  I do not
> understand the "chunking" that is used in "borg create". Please, if you
> can, point me to some documentation that explains this in some detail.

Chunking means to cut bigger files into smaller pieces (borg defaults to
~2MiB) before storing them into the repository. There should be some
words about it in our docs. See also rolling hash / buzhash.


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