Rick, thanks. This is pretty much what I figured. If you have done it on a 2621 it should also work on a 2811. I was worried about overhead as I heard this adds a lot.

But why do you have fragmentation disabled? Is it not needed?

It seems like we have or will have similar configs did you get the bandwidth expected after linking the T1s?

Daniel

It is there because the provider wanted it included when we configured the multilink. I thought about taking it out of my posting but decided to post the entire working solution. I have seen other multilink configs that do not disable fragmentation.

HTH

Rick

Can MLPPP be configured over an HDLC layer 2 circuit?

I've got 2 T1's that need to be bonded on a 2811 and 3 T1's that need to be bonded on a 3825. I'm not sure who provides one of the T's on the 2811 but do know the encapsulation is HDLC not PPP. Is this going to affect it in anyway?

I know it will be simple to change but I'm trying to minimize downtime and will plan around it if needed.

Also, with 2 different providers, is that going to affect the IP addressing for the interface?

If i set the interface with an IP address from 1 provider, will that affect the other DS1 from the 2nd?

multi 1 x.x.x.x x.x.x.x

ser0/0/0 no ip address (provider 1)

ser0/1/0 no ip address (provider 2)

allen

First and most important: I do not believe that there is any way to do MLPPP over HDLC. While PPP and HDLC are similar protocols there are differences and MLPPP is designed to use PPP.

It is not clear to me how much impact there would be if the T1s are from different providers. I have not ever done it and can not speak from experience about it. It seems to me that as long as the T1s originate on the same router and they terminate on the same router that MLPPP should work (since the providers do not know or care what is transported over the T1s why would it matter). There has been some suggestion in the forum that with different providers that there might be different latencies on the T1s and that might cause performance problems.

And I do not see that having different providers would impact the addressing. With multiple T1s you need an address for each T1. With MLPPP you assign the IP address to the virtual interface not to the T1s and you only need 1 IP address for the router when using MLPPP. And why would the provider care what IP address is on the interface, so long as the link originated on your router and terminated on your other router, then the provider does not see nor do they care about the IP addresses on the link.

HTH

Rick