Splitting a T1

[Revenant]

Ok... I need some help. I'm not too experienced with T1 connections before they hit the router. Situation is, I have a single T1 line coming into our building. I need to split that T1 line into two, so that I can use both WAN ports on the router. The reason is, we are switching over our DNS and T1 hosting services, so we are switching IPs et al. There is a built in overlap where we will have two DNS entries. But only one will be correct if we keep our current config during the switchover. So I need to split the T1 so that the router can have both of our outside IP addresses for the period of time that the switchover happens. One address (the old one) we will just translate until such a time as we disconnect the old one. This should only be in effect for one weekend, so we don't want to spend a lot of money. I have tried a hub, nogo, I have tried physcally splitting the wires (through a patch panel) nogo. Any other ideas?

[iamtheman]

OK first of all are you dealing with external or internal CSU/DSU's??

I would talk to your line provisioner/service provider about this. You can't just split a T1.

[Revenant]

Its an internal csu. I've looked at as much info as I can, and it looks like the hardware we'd need would be prohibitively expensive to use for 3 days. That's all I really need, but I doubt anyone's going to let us borrow a multiplexer, eh? I was just hoping maybe someone knew a cheap and easy trick to do it as a temporary solution.

[Revenant]

woohoo... Just found out that they are planning on bringing the T1 in on an unused circuit that we have. That means we have a dual t1 until we cancel our old service... hehehehhe... Also means we can use old and new T1 service to route all incoming traffic to the new IP addresses. Meaning, no lost mail, no lost traffic.

[Higg]

Even if you now are ok with your prob, the answer to the original question would be: NO, you can't split the T1 as your counterpart (provider) needs a Point-to-Point connection with the same speed for both on that line (T1 isn't used like Ethernet, where you can connect multiple stations on a bus).
But if you would have done this, you can use a secondary ip-adress on the router or install two virtual sub-interfaces on the physical int... one with the old network and the other with the new one... that would have been the solution...

Higg