Cisco Support Community
Community Member

C831 WAN interface bouncing

I have a cisco 831 that is configured for pppoe(dsl modem in bridge mode). It has been running fine for a couple months now, but just in the last few days, my eth1 interface connected to the dsl modem keeps bouncing 2 or 3 times per hour. The light for the eth1 int on the front of the unit actually goes off and on. Also when this happens the LAN side shuts down and I cant ping it from the inside(lights stay on). I have taken it out of service for testing now. I have it reconfigured for basic dhcp from a cable modem. It hasn't crapped out yet and its been downloading steady for about 45 minutes.

Attached is my config for the router in pppoe mode. Can someone tell me if there is a problem with it?


Re: C831 WAN interface bouncing


As mentioned in your post if the LED on the Cable modem goes off then better check out the connectivity getting terminated on the cable modem.

If thats not the case i would suggest you to have a look at your NAT overload statement and alter the same..

do add the below statements and try..

No ip nat pool xxxx x.x.x.x x.x.x.x 130 prefix-length 24

No ip nat inside source list 101 pool xxxx overload

Ip nat inside source list 101 interface dialer 1 overload

if you are unable to remove the nat statements do a clear ip nat translations * and try the same...


CreatePlease to create content