Multiple PPOE over multiple ADSL lines

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Bern

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Hi there,

I have finally managed to get multiple PPoE accounts to run over a single ADSL line, what I was wondering is if it is possible to run a PPoE link over mutiple ADSL lines. I doubt it, but thought it might be interesting. For two reasons- firstly for added bandwidth and secondly for redundancy.

So to give you the idea:
Could I set two ADSL gateways in bridge mode, and then connect them via their LAN ports. Then I connect my multi WAN router to the modems, each router-to-modem connection being a single PPOE link.
The theory is that either the PPoE will associate with one of the ADSL lines only, but not sure how this would work exactly. Then if one ADSL line fails the PPoE link will just associate with the other ADSL line.

The alternative is of course to set up multiple PPoE on each ADSL line, the same PPoE connections for both and thus have redundancy. This requires the ISP to allow multiple concurrent connections, so will not work for the uncapped accounts.

Anyone have any ideas on the above? I just don't know enough about the workings of ADSL and the PPoE connections.
 
It's illogical captain.

The 0.5 seconds that it takes to establish a new PPPOE connection makes having PPPOE connections available and on-line ready to switch to a silly requirement.
Besides, the aim is not to consume as many network resources as you can, the aim is to be as efficient as possible with the resources that you need.

Blerry consumer!
:p\

But, if you want to multiplex multiple connections, there are ISP's that will provide the landing point for that, at a price.
 
Point taken, but what I am looking at is if you want to seperate various network services via different ISP accounts AND have redundancy from the actual ADSL lines it starts getting fairly complicated, so rather than setting up a fairly complex routing scenario I was wondering if it would be possible to let the PPoE connections sort it out and maybe if there were a way to select a "preferred" ADSL modem. Ideally you should not really have to worry about this sort of thing, but in my experience with ADSL it is not the most reliable service- for example I had to get the ports rest at my home connection on average twice a month over a 4 month period as Telkom couldn't keep a stable connection for whatever reason.

Imagine you have a local only ISP acount for a VPN to a remote site, an account for VOIP (unshaped) and one for normal data (browsing and email). Now you want to also ensure that if one of your ADSL lines goes down the services will all run on the remaining line automatically. Now to start setting up the routing for this with the same PPoE accounts on multiple ADSL lines with failover is a fair amount of work and requires a few workarounds potentially, so was basically musing if there was an easier way..
 
Add this is in a geographically remote location and possibly that you could get the two ADSL lines from different exchanges to improve redundancy.
 
I you have 2 lines for redundancy:
I would have one ADSL line go to one exchange, and the other go to another exchange if at all possible, and most times it is.

I would:
- Have a Linux machine with 3 network cards
- Purchase 2 ADSL modems (or ADSL routers in bridge mode), call them ADSL Main and ADSL Back.
- Plug the local network into network card 1, cal it ETH0.
- Plug the ADSL Main into network card 2, cal it ETH1.
- Plug the ADSL Back into network card 3, cal it ETH2.

Then, I would run a script that monitors for all PPPOE sessions fail, which could simply monitor output from the "plog" command.

When the sessions fail, I would:
- poff ALL the ADSL sessions.
- turn off ETH1 and ETH2.
- switch the mac rules on ETH1 and ETH2 around.
- re-enable ETH1 and ETH2.
- pon ALL the ADSL sessions.
This would in effect switch communication to the other ADSL modem/router, without changing any routing configurations.

i.e. A soft network card switch instead of tricky networking.
That will be R800 thank you.
 
Yup .. 2 different exchanges would be ideal, like you said.

NOTE that the trick of switching ETH1 and ETH2 around can also work for switching ETH1 and USB1 around for an E220. Linux is like that.
 
Based on your description I would say no. To do what you want to do is going to require PPPoE Multilink, a service which I'm pretty sure is not offered by any ISP in SA. Vox however does something similar but not quite what you described.

But then again maybe I'm understanding you wrong in which case you would have to forgive me :)
 
The problem is you still need to do some config when one of the lines fail, failover is not automated. So that means either a sure means of getting remote access (dial up, 3G or such) or get a non technical person there to just plug the cables from the router in to the working ADSL line modem- all of which would lead to some downtime and frustration. I would go with switching cables as it is easy to understand and can be done by anyone in the event of a failure, easy to set procedure for local staff that way. But imagine if you could have it all automated...

The first installment of your fee will be sent by normal post, 5c each quarter;P
 
I realise this is the case, just was hoping there might be another way where I could have some control and not have to pay much higher rates. I only need the better quality bandwidth for some services and would like to take advantage of the cheaper, shaped options for things like browsing and downloads. We can dream can't we?
 
Bern said:
The problem is you still need to do some config when one of the lines fail, failover is not automated. So that means either a sure means of getting remote access (dial up, 3G or such) or get a non technical person there to just plug the cables from the router in to the working ADSL line modem- all of which would lead to some downtime and frustration. I would go with switching cables as it is easy to understand and can be done by anyone in the event of a failure, easy to set procedure for local staff that way. But imagine if you could have it all automated...

The first installment of your fee will be sent by normal post, 5c each quarter;P
Click to expand...
Heh?
The swapping of ETH1 and ETH2 is 100% automated using really simple scripts.
I currently do this for Virtual Machines that are moved into and out of a production environment based on their network masks.
 
Sorry Davemc, reading in a hurry - see you noted a softswitch. I will try it out and see how it goes, thanks for the suggestions.
 
well the big question is,when i dial a pppoe connection how is the bridge modem decided ?
 
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