backup

[James Wilkinson]

Vano Beridze wrote:
> I have a PC at work and I want to backup data on  a regular basis.
Very good idea.

> I want a simple backup of some files, to some file I think would be
> enough.

Well, you have lots of options here, depending on the size of the files.

One set of options is to copy files onto removable media: depending on
the size of the files, that could be floppy, a USB key, a CD-R or CD-RW,
a DVD-R/W, or tape. Depending on the media, you could either mount it
and copy the data onto it, use cdrecord, or tar. There's also the
possibility of using gzip to reduce size. [1]

Another set is to copy the files over the network. Depending on how fast
your network is, this could involve nfs to another local Unix-like
computer, smbfs to a Windows PC, or rsync (which cuts down on the amount
of data that needs to be copied every time, if it doesn't change much).

If you're copying to a computer on the public Internet, you should set up
an SSH or VPN tunnel (or just use sftp) to secure this. (Many people
report that sftp is considerably faster than NFS or SMB over high-latency
Internet links.

If you're happy with using the command line to do this, then you really
should look at putting it into a script. If you aren't going to need to
change media, then you should look at putting a reference to that script
into the system crontab. Then, apart from occasionally checking that it's
all working, you can just leave it going.

I'd recommend against copying onto the same computer. There's way too
many opportunities for the original and the backup to get destroyed at
the same time. Likewise, you really should make sure there is a certain
amount of distance between the original and your backups at all times
(which implies at least two sets of backup media).

I don't know how big your work is, but if you have any network
administrators, go have a chat with them. Most network backup programs
these days have Linux clients, so they may want to use that. Otherwise,
there may be somewhere suitable on a server for you to copy your data.

Think about *what* you want the machine to do, and then ask about *how*
to do it.

Hope this helps,

James.

[1] In my experience, bzip2 is too slow and doesn't give enough extra
compression to be worthwhile when backing up to local media.
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