Cisco3640

[RadioX]

Ok here is my options. I am looking for some advice on which way would be the best or even a better idea if someona has one.

Here is my current configuration
4 T1's from Cable and wireless running BGP4 on a Cisco3640 with 128mb ram accepting partial routes.

Here is what I want to do
1.) Add 4 more T1's from Cable and Wireless. The question is is this possible? Can a Cisco3640 handle 8 T1's efficiently? I have been told that 8 T1's muxed together is not a good idea why or why not?

2.) If it is not a good idea to mux 8 of them together how about 6 (which I was told is the limit). If I do this here is what I will need to do. I will ned to divide out my mails ervers (say on 2 T's) and leave the rest of my production on the 6 T's. What kind of subnetting issues am I going to run into? I will have to keep my production on the class C it is on and put my mail on another class C. I do not have layer 3 switches. So theoretically when one of my sites spools its mail it will have to go out one pipe and come in the other. With as much mail as we send out this is not a very good option. Is there any way around this.

If you need some more information please ask and I will be happy to explain more of whatever you need

Thanks for your time and assistance
Ron Withers
Network Engineer

 

[wybnormal]

When I worked at one of the leading wireless ( cell) companies, the rule of thumb was 5 Ts, it was time to get a T3.. this is assuming you are actually using all the bandwidth. I have a 3640 right now running a T3 with 2 T1s and no problem but then the T3 runs a constant 3-5Mbps and the Ts are running about 70% nominal.

I dont know why you couldnt mux the Ts.. the 7500 series router has a 8 port card. Were they referring to the muxing as bad or just the 3640 couldnt handle the load?

I dont what kind of subnetting issues you are talking about.. you need 16 IPs.. mask of 255.255.255.252 if you want to run them point to point. Something like OSPF or EIGRP can load balance a few different ways between them, policy routing if you want to force SMTP over a certain T(s) and there are other tricks to be used.

MikeS
"Diplomacy; the art of saying 'nice doggie' till you can find a rock" Wynn Catlin

 

[RadioX]

Mie,

Thanks for the reply. I am interested in this policy routing concept. Do you have any samples of code or anything like that or a hint where to start looking at some of this information.

Thanks Again
Ron

 

[wybnormal]

This is one of the easiest papers Cisco has on it. Very useful

Understanding Policy Routing

http://www.cisco.com/warp/public/105/36.html

MikeS
"Diplomacy; the art of saying 'nice doggie' till you can find a rock" Wynn Catlin