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New Member

Combining two ethernet connections (T-1's) for load-balancing

I've got two Internet connections (two different T1 connections) that I'd like to combine and load-balance through the firewall. I've got an ASA5510 (and I know I can't do it with this unit), my question is: Can I do this with a different model? Would it be better to do this after the data has passed through the firewall? Basically, I had a fileover system (if T1 #1 went out, then T1 #2 would take over) but I'd rather use both and if one goes down, then I'll accept the lower speed until I get the connection re-established.



New Member

Re: Combining two ethernet connections (T-1's) for load-balancin

See if your provider will provide MLPPP (Multilink PPP). It will do exactly what you want. I'm not familiar with the ASA's, but I have done this several times with the new ISR's (2800 & 3800 series routers w/ Advanced Security IOS - Firewall, IPS, etc)

New Member

Re: Combining two ethernet connections (T-1's) for load-balancin

Hi Clay,

There are some clarifications needed here. One thing is whether both the internet connections are for the same provider which i dont think the case is. If i am right, then u need to run BGP to do loadbalancing for which u will need several things like your own subnet, router and co-ordination with ISP. Or else there is also one more option of using a Radware linkbalancer kind of device which will solve your problem currently, but u will have to think of scalability.

Anyhow, if you find the note useful, dont forget to vote.


Naveen B

Hall of Fame Super Silver

Re: Combining two ethernet connections (T-1's) for load-balancin

I do not believe that there is any model of ASA which can terminate T1 connections. So if your connections are T1s then I believe that you will need some router positioned outside of the ASA. This router would terminate the T1s, pass incoming data to the ASA for evaluation and processing, and would route data outbound from the ASA. If the two T1s originate from your router and terminate at the same place then multilink ppp may be an attractive alternative (as suggested in a previous response). If they do not terminate at the same place then some routing logic may be needed. And if they are to 2 different providers then BGP may well be called for. Implementation of primary/backup or of load sharing should be possible for either of the alternatives that are not MLPPP.



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