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Cisco 2811 Router Connected to Fractional T1 how to connect another router to it?

Hi out USA office has just had a Cisco 2811 Router put it for carrying their PBX trunks via VOIP and AT&T.

The router provides an interner connection as well.

The documentation supplied shows this as connecting on FE0/0 (Fast Ethernet 0/0) and indeed if you connect a PC with a straight RJ45 cable the light come on on the network ports and you get internet/

We already have an internet (DSL) connection so we want to use this extra capacityfor load balancing and redundancy.

We have bought a suitable router to connect to both internet connections (draytek 2820) but are having problems connecting this to the CISCO.

A PC connected to the FE0/0 port gets an IP and works. The router connected to the FE0.0 doesn't even show any lights for the physical connection, regardless of using a straight or crossover cable.
We have also tried connecting the FE0/0 ports and the draytek ethernet WAN port to a switch which gets the lights on both but the draytek still doesn;t get an IP address unlike the PC and configuring manual IP with the IP''s supplied doesn't work.

Am I missing something on whats required to connect anohter router to the Cisco?

Please bear in mind as an AT&T supplied router I have no access to its config.
Also We are in the UK providing support to our US subsidiary so we have no direct contact with AT&T

Thanks for any help you can give me on this.


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8/22/2022 - Mon

Ok since you got the interfaces to come up with an ethernet segment I would stick with this configuration. I would make sure you have a default route in your draytek that points to the Cisco. Now here is the tricky part you have to run NAT on the Draytek if you have no access to the Cisco because the Cisco will not know how to get to the network on the other side of the Draytek, unless AT&T can put a route in the Cisco for you. So everything has to appear as it is coming from the same subnet as the the AT&T router. NAT should do it.

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