Hi,

I am interested in doing automatic incremental backups of files on my linux boxes. The idea is to do this over the web (offsite) in some secure manner between 2 RH7.2 systems. I have looked but have not found anything on the subject that is not commercial (lots of commercial options though..). Maybe a vpn? Any suggestions greatly appreciated.

Saludos.

I would definetly use VPN because you don't want your backups going across the internet unencrypted. I would also suggest using CIPE for your VPN. Its easier to configure then other VPNs and its very secure. Once you have CIPE setup you can ping the other machine as if it was on your LAN. Then to backup to the other machine I would use the dump command. Something like:

dump 0uBf 500000 hollywood:/dev/nrf0 /dev/hda7

This would do a backup of /dev/hda7 onto the tape drive(/dev/nrf0),or whatever, on the machine hollywood. Man dump for more info.

Unison over ssh works well:

http://www.cis.upenn.edu/~bcpierce/unison/

It can also check for changes so that you dont have to back up a whole dir to ensure one file is safe

Thank you both for your quick response. I have already set up a vpn using cipe and the Unison link sounds promising. If I may:

Running a vpn between the linuxes, could I "link" both private networks? I mean, if I have a windows machine behind each Linux could I see the other machine on my network neighbourhood? Again, I have set up the vpn and can ping from one linux to the other but dont know how to proceed.

Saludos.

I guess, and don't quote me on this, you could put another nic card in the linux machines acting as the CIPE servers. Cipe servers are basically encrypted routers so you could just treat them like one and hook up the other boxes to the CIPE server.

Ive done this using the "remote announce" directive in samba. Just have the remote announce address on each machine set to the local cipe address of the other machine.

man smb.conf:

remote announce (G)
This option allows you to setup nmbd(8) to periodically announce
itself to arbitrary IP addresses with an arbitrary workgroup
name.

This is useful if you want your Samba server to appear in a
remote workgroup for which the normal browse propagation rules
don't work. The remote workgroup can be anywhere that you can
send IP packets to.

Sorry I didnt respond earlier.
Unison is excellent for synchronizing files over the internet. I found it to be simple to use. However, I found rsync better suited for my needs...I only wanted to "mirror".

As for the 2d. question, remote announce is deffinitely the way to go. Tnx for your help. I honestly should have read the samba documentation as it very clearly explains it all in the chapter "Cross Subnet Browsing". Maybe this will help someone else....