-----Original Message----- From: centos-bounces@centos.org [mailto:centos-bounces@centos.org] On Behalf Of Rudi Ahlers Sent: Wednesday, 28 April 2010 11:11 PM To: CentOS mailing list Subject: [CentOS] how to reroute all ADSL traffic via another server on theinternet?
Hi all,
Does anyone know, if it's possible to reroute all (i.e. HTTP / FTP / DNS / SMTP / POP3 / IMAP / etc) from an ADSL connected machine via another server, which is currently hosted with IS and has full internet access?
i.e. Can I setup another machine, on a different public IP than the dynamic ADSL IP as default gw? OR do I need todo something on that machine to work as a router for such a setup?
Both servers in this case is CentOS linux, but I'm sure that won't make a big difference?
You could use GRE tunnelling, which is supported by Linux and Cisco among others.
You could set up a GRE tunnel between your two sites, assign a /30 for the link, and route most traffic over the GRE interface (Minus the IP Address of your remote site - it must be routed via your internet connection).
This will behave as a point-to-point link between your sites.
Check out the ip(8) command, in particular the ip tunnel commands.
But, something like this should be a nice start:
ip tunnel add Tunnel0 mode GRE remote 1.2.3.4
ifconfig Tunnel0 10.10.10.1 netmask 255.255.255.252
ip route add 1.2.3.4/32 via 6.7.8.9
Cheers,
Dan