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New Member

VPN through Cisco 827 / 837

Hello i am having avery bizare problem,

i am setting up a vpn connection, as follows :


i am using the windows XP VPN client to connect to my corporate server .

when i am using a normal modem (ALCATEL speedstoucvh pro etc ) i can connect without any porblems.

but when i connect my cisco router, it just dont work.

i have tried with cisco 827 ans cisco 837, it just wont work .

i started a configuration from scratch, it worked for some time, but then it just stopped, i switched my alcatel back and it worked, put cisco back again NOT WORKING.

here is my router config:

Building configuration...

Current configuration : 1166 bytes

version 12.2

no service pad

service timestamps debug datetime msec

service timestamps log datetime msec

no service password-encryption

hostname VPN_RTR

ip subnet-zero

ip audit notify log

ip audit po max-events 100

interface Ethernet0

ip address

ip nat inside

no ip mroute-cache

hold-queue 100 out

interface ATM0

bandwidth 1025

no ip address

no ip mroute-cache

no atm ilmi-keepalive

pvc 8/35

encapsulation aal5mux ppp dialer

dialer pool-member 1

dsl operating-mode auto

dsl power-cutback 1

hold-queue 208 in

interface Dialer0

bandwidth 1024

ip address negotiated

ip nat outside

encapsulation ppp

dialer pool 1

no cdp enable

ppp authentication chap callin

ppp chap hostname xxxxxx

ppp chap password 0 xxxxx

ip nat inside source list 8 interface Dialer0 overload

ip classless

ip route Dialer0

ip http server

access-list 8 permit

scheduler max-task-time 5000



Re: VPN through Cisco 827 / 837

What version of IOS are you using? Can you please provide the exact ios filename on your router?

New Member

Re: VPN through Cisco 827 / 837

System image file is "flash:c820-oy6-mz.123-19.bin"


Re: VPN through Cisco 827 / 837

Initially I thought it might be an IPSec NAT traversal problem but I have just confirmed that the IOS you have does support NAT traversal. At the moment I do not have any other recommendations other than trying to do some debugs while establishing the connection.