CentOS - Apr 2010 - how to reroute all ADSL traffic via another server on the internet?

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?

-- 
Kind Regards
Rudi Ahlers
SoftDux

Website: http://www.SoftDux.com
Technical Blog: http://Blog.SoftDux.com
Office: 087 805 9573
Cell: 082 554 7532

Rudi Ahlers sent a missive on?2010-04-28:
> 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?
>
In principal yes you can do this type of thing. You'll have to enable
ipforwarding on the gateway machine as a minimum.

Can you provide more information about your networking setup - ip addresses
and subnet masks, with an ascii drawing as well would help if you think it
relevant :-), then we can provide detailed answers :-)

Thanks

Simon.

Simon Billis sent a missive on?2010-04-28:
> Rudi Ahlers sent a missive on?2010-04-28:
> 
>> 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?
>> 
> 
> In principal yes you can do this type of thing. You'll have to enable
> ipforwarding on the gateway machine as a minimum.
> 
> Can you provide more information about your networking setup - ip
> addresses and subnet masks, with an ascii drawing as well would help
> if you think it relevant :-), then we can provide detailed answers :-)
> 
> Thanks
> 
> Simon.
>
Sorry miss read your post - you can do what you're after, but this is a
proxy in this case.... i.e. the remote box is acting as a proxy for your
adsl connected server. If you're wanting to route all the traffic from your
adsl connected box to the remote server, then I would look at using a VPN
between the boxes.... you might be able to use squid on the remote server to
be your proxy also.

S.

Rudi wrote:
>
> 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?
<snip>
I don't quite understand what you're asking. Do you mean
 <ADSL system><-><hosted system><->the 'Net
or do you mean
<the 'Net>-><hosted system>-><ADSL system>
?
That is, are you trying to offer Web, FTP (BAD idea, use sftp or scp), and
email from your ADSL-connected server, or do you want to connect to the
'Net via the hosted system?

      mark

On 04/28/2010 02:11 PM, Rudi Ahlers wrote:
> 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?
all you need is 'man ip'. Setup the right gateways on each machine, 
setup your ip policy into the right rules, route the rules from / to 
wherever you want.

- KB

From: Rudi Ahlers <rudiahlers at gmail.com>
> 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?
Maybe you wann have a look at: http://lartc.org/howto/

JD

>-----Original Message-----
>From: centos-bounces at centos.org 
>[mailto:centos-bounces at 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