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Cisco 2811 with external ADSL2+ Modem

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gmitch79

Technical User
Jul 12, 2007
7
AU
Hi All,



I would just like to ask has anyone configured a ADSL2+ Modem through the fast ethernet port on a CIsco 2811 router if so can some please point me in the right direction on configuration for it.


Thanks
Gmitch79
 
Is the encapsulation on the line PPPoE, and if so, do you plan to have the modem do the NAT and PPPoE negotiations? If so, then just...
2811>en
2811#conf t
2811(config)#int fa0/0
2811(config-if)#ip add dhcp
2811(config-if)#exit
2811(config)#ip route 0.0.0.0 0.0.0.0 (IP address of the modem ethernet interface)
Also, you may have to hardcode the fa0/0 for half-duplex if the modem only offers half duplex...
2811(config)#int fa0/0
2811(config-if)#duplex half (or if the modem offers full, then duplex full)
2811(config-if)#end
2811#wr
Let me know how this goes---you may have to set the modem into bridge mode and configure the router to have a dialer interface by way of virtual access and virtual template. I have a 2620XM, and my modem is screwy, so I bought a WIC-1ADSL. This will replace my Cisco 837.

Burt
 
Thanks Burt

will this muck around with the cisco call manager that is setup at the moment if i add in the ip route.


Gazza
 
sorry i also wanted to control it all with the 2811 and just have the modem as a modem only no routing, yes the line is PPPoe and i do not want it to do nat.


Thanks


Gazza
 
If you don't do any NAT, will that leave you wide open from the internet?

***************
R. Corrigan Jr.
Network+, (working on CCENT+CCNA)
 
with the modem in bridged mode then yes you will be wide open. you should have a firewall in place for your lan.

although nat does provide some protection by only forwarding based on the rules you create... that was not its original intention as it was designed to save public addressing.
 
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