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Re: [PLUG] Self-hosted online backups?
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Sorry for top-posting; on my blackberry.
Has anyone suggested boxbackup yet? Client/server model, key-based authentication and encryption, client-side compression iirc (to save on b/w), and best of all: free/opensource.
(lack of GPG due to message sent via blackberry device)
-----Original Message-----
From: Richard Freeman <r-plug@thefreemanclan.net>
Date: Fri, 04 Dec 2009 12:15:50
To: Philadelphia Linux User's Group Discussion List<plug@lists.phillylinux.org>
Subject: Re: [PLUG] Self-hosted online backups?
Gordon Dexter wrote:
> Well it seems that part of JP's dilemma is what program to use. He
> seems to require that the backup is:
> a) always encrypted on the backup server
> b) space/bandwidth efficient
>
Lots of solutions provide either of these in isolation - finding both is
harder.
First, if you encrypt on the client side then you immediately limit
space efficiency from storing sparse files (finding identical files from
different hosts/etc and transmitting/storing them only once). The
server doesn't know what any of the files actually are, so it can't tell
if they're identical. Two identical files from different clients will
have different keys and thus they won't be the same. Even if you knew
two files were the same you couldn't store only one copy unless the
clients had access to each other's decryption keys for a restore or at
least trusted each other enough to share a session key.
However, a client can keep track of what was sent to the server, so it
can be efficient with regard to incremental backups, and possibly even
sending only modified parts of individual files.
If the server can decrypt everything (maybe it is sent SSL over the net,
but the client trusts the server), then there are a lot of other
options. A client wouldn't upload files the server already has - it
would just register a copy of the file, and so on.
The best model depends on your requirements like anything. The trust
model for the clients/servers has a big impact. You might trust the
clients but not the server. A service provider might even trust the
server but not the clients (the server might not want to tell clients if
a given file is already in the store - it would just accept the file and
then secretly store it in a sparse manner). For some people storage is
cheap, and for some people bandwidth is cheap. Some people care about
only hardware failure, and some people care about loss of an entire
facility (fire/flood/etc).
The important thing is to UNDERSTAND your needs, and UNDERSTAND the
limitations and advantages of the solution you choose.
___________________________________________________________________________
Philadelphia Linux Users Group -- http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion -- http://lists.phillylinux.org/mailman/listinfo/plug
___________________________________________________________________________
Philadelphia Linux Users Group -- http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion -- http://lists.phillylinux.org/mailman/listinfo/plug
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