If a computer is not directly accessible from the computer on which dirvish is running, it is still possible to backup that computer using ssh through a third (middle) computer. An example of when this can occur is when the target to be backed up is behind a firewall or gateway.
http://samba.anu.edu.au/rsync/firewall.html gives the basic information that I used to setup dirvish to do this. I used method one, but the other methods would probably work also.
Suppose you have three computers as follows:
Computer A - the dirvish backup server
Computer B - the gateway - gateway.mydomain.com
- Computer C - the remote computer that you need to backup to A. Computer C is on a LAN behind B, and can only be accessed directly by other computers on its 10.0.0.* network. Suppose its IP address is 10.0.0.30.
Setup the dirvish default.conf as follows:
client: username@10.0.0.30 <<BR>> rsh: ssh username@gateway.mydomain.com ssh <<BR>>
- ..
This will cause rsync to be run with the -e option as follows:
rsync -e "ssh username@gateway.mydomain.com ssh" username@10.0.0.30
This will ssh to gateway.mydomain.com and ssh from there to 10.0.0.30, creating sort of a poor-man's tunnel over which the data will be transferred. To get this working, you will obviously need to setup ssh keys to allow computer A to login to computer B without any prompts and to allow computer B to login to computer C without any prompts.