One PC connecting to multiple ISPs at once via one ADSL modem?

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ant1b0dy

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I understand that using a pppoe connection allows you to connect to different ISPs using the same ADSL modem and line. Is it possible to connect to 2 different ISPs from the same PC and have certain traffic routed through the one connection and other traffic through another?

Thanks
 
ant1b0dy said:
I understand that using a pppoe connection allows you to connect to different ISPs using the same ADSL modem and line. Is it possible to connect to 2 different ISPs from the same PC and have certain traffic routed through the one connection and other traffic through another?

Thanks
Click to expand...

Can be done - I have posted on this topic a few times:

http://mybroadband.co.za/vb/showthread.php?t=36773

and

http://mybroadband.co.za/vb/showthread.php?t=36667

The "trick" is in the routing.

EDIT: happy to assist where I can - just ask specific questions (and accept that I am a n00b at this too!)
 
You know - if it were not for Telkom, and we all had fast, unshaped, uncapped ADSL we would never have learnt these things....

Necessity is the mother of invention.
 
I don't see multihomed routing working since the gateways won't have static addresses.

AFAIAA, and if I understand ant1b0dy's requirements correctly, the only way to do this on windoze is with a little app called RASPPPOE. Window$ doesn't permit multiple concurrent pppoe connections, but RASPPPOE does. So you connect pppoe1 and pppoe2. You now have 2 gateways which, IME, Winblows doesn't like too much. Trash both gateways, add manual routes for your specific needs through 1 connection then configure the default gateway to the other connection.

This is how some people routed their traffic intelligently when we were still soft capped : specific manual routes for the local subnets via a capped account and everything else through an uncapped account.

Let me know if you want more specific info / instructions - think I've still got the howto somewhere in an inbox.... maybe :cool:
 
masticore said:
I don't see multihomed routing working since the gateways won't have static addresses.

AFAIAA, and if I understand ant1b0dy's requirements correctly, the only way to do this on windoze is with a little app called RASPPPOE. Window$ doesn't permit multiple concurrent pppoe connections, but RASPPPOE does. So you connect pppoe1 and pppoe2. You now have 2 gateways which, IME, Winblows doesn't like too much. Trash both gateways, add manual routes for your specific needs through 1 connection then configure the default gateway to the other connection.

This is how some people routed their traffic intelligently when we were still soft capped : specific manual routes for the local subnets via a capped account and everything else through an uncapped account.

Let me know if you want more specific info / instructions - think I've still got the howto somewhere in an inbox.... maybe :cool:
Click to expand...

Masticore is right. Winblows does battle - I cannot even seem to set up which connection does what, short of the routing.
What I wanted, was basically to route specific IPs via IS ADSL (is news server, my IS hosted server, and our office VPN). Everything else, which is low usage, via SAIX - so no routing needed as windoze used the PPPOE bridge connection as the default Internet connection anyway.
 
@Moederloos :

I'm not sure why, but I'm assuming you're NOT establishing 2 PPPoE sessions from one machine, but have connectivity through a router AND a single PPPoE session in windoze. If so, your requirements are easily met. If not, sorry.

TCP behaviour is to check specific routes first, so if the routes exist they'll be "obeyed" - traffic will follow the specific route before traipsing off to the default gateway.

I'll assume your router is connecting with the IS account and your PPPoE session is with the SAIX account. For demonstration purposes, I'll use the following IPs :

IS session : 196.209.1.1 (although this is irrelevant)
SAIX session : 165.146.1.1
LAN address of your router : 192.168.0.1

Once you've established the PPPoE session, your default gateway (0.0.0.0 - check this by entering "route print" in a DOS prompt) will be the SAIX address (165.146.1.1). Depending on your LAN card's TCP settings you may have 2 gateways (the second most likely being 192.168.0.1). If you do have 2 gateways, remove the gateway configured on your network card.

Add persistent static routes to the IS machines / networks by entering this in a DOS prompt :

(((sample for news.is.co.za - ping the boxes to get their IPs)))
route add 168.209.98.66 mask 255.255.255.255 192.168.0.1 -p

The "-p" at the end will force the route to stay in the TCP routing table so it'll still be there after reboots / BSODs. Expanding on masks and subnets is beyond the scope of this post.

With the route in place, all traffic to that IP address (or network - once you've figured out subnets) will follow the specified gateway (the router's LAN address.) The router will route the traffic accordingly through its internet connection.

POP
 
@masticore:
My modem doesn't support pppoe connections while in router mode like moed's does. How would I go about setting this up with 2 pppoe connections? Would I first have to connect to the ISP that would be my default connection? Thanks.
 
ant1b0dy, if your router does not support concurrent router and bridge modes then you have to put the router in bridge mode and establish 2 pppoe sessions (on windo$e use RASPPPOE, otherwise use *nux).

Because you'll now have 2 dynamic address, you cannot create the persistent route and you'll have to create the routes everytime you connect. PITA, but it's the only way.

Assume you connect an IS account and a SAIX account and want to route to IS's news server through the IS account and everything else through SAIX. Also, assume your IPs are :

IS = 196.209.1.2
SAIX = 165.146.1.3

then from a DOS prompt, first trash your default gateways with :

route delete 0.0.0.0

then add the correct default gateway you want (SAIX) :

route add 0.0.0.0 mask 0.0.0.0 165.146.1.3

and also the specific routes you want to IS (their news server in this instance) :

route add 168.209.98.66 mask 255.255.255.255 196.209.1.2

EVERY TIME you connect a PPPoE sessions, Windoze is going to screw up your routes so you have to recreate them.
 
Thanks masticore, it sounds simple enough. Methinks I'll have to write a proggy to automate the connection and route setup to make this less painful... :)
 
ant1b0dy said:
Thanks masticore, it sounds simple enough. Methinks I'll have to write a proggy to automate the connection and route setup to make this less painful... :)
Click to expand...

One problem I can see, is the auto-disconnects (24 hourly etc).
Is it not possible to do a 165.0.0.0 type thing?
 
Moederloos said:
Is it not possible to do a 165.0.0.0 type thing?
Click to expand...

What exactly is a "165.0.0.0 type thing" ?
You mean route all traffic to a 165.x.x.x address (although you'll only want to route 165.165 and 165.146) through your SAIX account ? If yes, then :

route add 165.165.0.0 mask 255.255.0.0 165.146.1.3
route add 165.146.0.0 mask 255.255.0.0 165.146.1.3

notice the use of a different mask ? The mask indicates whether the destination is a network or host.


Moederloos said:
One problem I can see, is the auto-disconnects (24 hourly etc).
Click to expand...

Yes, the 24-hour zap is the primary PITA.


Moederloos said:
How can I route P2P over a specific connection?
Click to expand...

You cannot route based on traffic type, only by destination. Well, not unless you have some very impressive and expensive router with deep-packet inspection.
 
masticore said:
What exactly is a "165.0.0.0 type thing" ?
You mean route all traffic to a 165.x.x.x address (although you'll only want to route 165.165 and 165.146) through your SAIX account ? If yes, then :

route add 165.165.0.0 mask 255.255.0.0 165.146.1.3
route add 165.146.0.0 mask 255.255.0.0 165.146.1.3

notice the use of a different mask ? The mask indicates whether the destination is a network or host.




Yes, the 24-hour zap is the primary PITA.




You cannot route based on traffic type, only by destination. Well, not unless you have some very impressive and expensive router with deep-packet inspection.
Click to expand...


Thanks masticore - my last post was not very eloquent - what I am suggesting is the "reverse"

route add [specific ip, say news.is.co.za] MASK 255.255.255.255 165.0.0.0. -p

So, a specific IP will route via a gateway that begins 165....

Does not seem doable?
 
@masticore:

You seem to be the routing guru so here's another question for you. Is there a practical limit to the number of static routes you can add to you network config, i.e. at what point does the number of routes start hampering your general network performance?

I want to set up static routes so that I can route all South African ("local") based connections through a local only account and have everything else go through a regular international account. I have a database of all the IP ranges of SA based networks and after some investigation I've found that with static routes set up for just the top 100 networks (in terms of size) I can cover 99.2% of all the IP ranges assigned to SA. With just the top 50 networks I can cover 92.3% of the IP ranges.

Basically I just need to know whether Windows XP can handle so many routes or if it'll curl up and die. :)
 
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