Cisco router 2900 not pinging the internet

Monique · ‎04-15-2019

My Cisco router 2900 connected via interface vlan1 to ISP modem accesses the internet for just 5mins and after 5mins, the internet is no more accessible. I can access the internet non stop when I connect to the radio directly via a PC. But my LAN users and router cant access the internet after 5mins. Any idea what could be the issue. Thanks

Mark Malone · ‎04-15-2019

Hi
any logs from the router when the issue is occurring ? show loggs

I can access the internet non stop when I connect to the radio directly via a PC
Do you mean you are directly connected to the modem you see no dropped connection ?

Monique · ‎04-15-2019

I mean when I connect to the radio directly via laptop, I have access to internet with no constraints.

Mark Malone · ‎04-15-2019

Need to see the logs from when the issue is occurring to see whats happening on the router

Monique · ‎04-15-2019

A#sh log
Syslog logging: enabled (0 messages dropped, 3 messages rate-limited, 0 flushes, 0 overruns, xml disabled, filtering disabled)

No Active Message Discriminator.

No Inactive Message Discriminator.

Console logging: level debugging, 140 messages logged, xml disabled,
filtering disabled
Monitor logging: level debugging, 0 messages logged, xml disabled,
filtering disabled
Buffer logging: level warnings, 67 messages logged, xml disabled,
filtering disabled
Exception Logging: size (4096 bytes)
Count and timestamp logging messages: disabled
Persistent logging: disabled

No active filter modules.

Trap logging: level informational, 143 message lines logged
Logging Source-Interface: VRF Name:

Log Buffer (51200 bytes):

*Apr 13 18:01:03.247: %LINK-3-UPDOWN: Interface GigabitEthernet0/0, changed state to up
*Apr 13 18:01:03.251: %LINK-3-UPDOWN: Interface GigabitEthernet0/1, changed state to down
*Apr 13 18:01:03.251: %LINK-3-UPDOWN: Interface GigabitEthernet0/2, changed state to down
*Apr 13 18:01:34.031: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to up
*Apr 13 18:02:34.815: %CRYPTO-4-IKMP_BAD_MESSAGE: IKE message from 62.173.40.227 failed its sanity check or is malformed
*Apr 13 18:03:45.107: %CRYPTO-4-IKMP_BAD_MESSAGE: IKE message from 62.173.40.227 failed its sanity check or is malformed
*Apr 13 18:03:54.963: %DHCPD-4-PING_CONFLICT: DHCP address conflict: server pinged 172.16.130.64.
*Apr 13 18:03:54.963: %DHCPD-4-PING_CONFLICT: DHCP address conflict: server pinged 172.16.130.61.
*Apr 13 18:03:54.963: %DHCPD-4-PING_CONFLICT: DHCP address conflict: server pinged 172.16.130.62.
*Apr 13 18:03:54.967: %DHCPD-4-PING_CONFLICT: DHCP address conflict: server pinged 172.16.130.63.
*Apr 14 16:50:30.130: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to down
*Apr 14 16:51:10.242: %LINK-3-UPDOWN: Interface GigabitEthernet0/0, changed state to down
*Apr 14 17:06:44.242: %LINK-3-UPDOWN: Interface GigabitEthernet0/0, changed state to up
*Apr 14 17:06:54.086: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to up
*Apr 14 17:07:41.038: %CRYPTO-4-IKMP_BAD_MESSAGE: IKE message from 62.173.40.227 failed its sanity check or is malformed
*Apr 14 17:08:51.046: %CRYPTO-4-IKMP_BAD_MESSAGE: IKE message from 62.173.40.227 failed its sanity check or is malformed
*Apr 14 17:10:01.150: %CRYPTO-4-IKMP_BAD_MESSAGE: IKE message from 62.173.40.227 failed its sanity check or is malformed
*Apr 14 17:11:11.270: %CRYPTO-4-IKMP_BAD_MESSAGE: IKE message from 62.173.40.227 failed its sanity check or is malformed
*Apr 14 17:12:21.510: %CRYPTO-4-IKMP_BAD_MESSAGE: IKE message from 62.173.40.227 failed its sanity check or is malformed
*Apr 14 17:13:32.122: %CRYPTO-4-IKMP_BAD_MESSAGE: IKE message from 62.173.40.227 failed its sanity check or is malformed
*Apr 14 17:14:42.158: %CRYPTO-4-IKMP_BAD_MESSAGE: IKE message from 62.173.40.227 failed its sanity check or is malformed
*Apr 14 17:23:06.754: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to down
*Apr 14 17:23:15.242: %LINK-3-UPDOWN: Interface GigabitEthernet0/0, changed state to down
*Apr 14 17:40:45.242: %LINK-3-UPDOWN: Interface GigabitEthernet0/0, changed state to up
*Apr 14 17:40:53.510: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to up
*Apr 14 17:41:12.762: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to down
*Apr 14 17:43:33.242: %LINK-3-UPDOWN: Interface GigabitEthernet0/0, changed state to down
*Apr 14 17:44:19.782: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to down
*Apr 14 17:44:26.734: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to up
*Apr 14 17:44:45.142: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to down
*Apr 14 17:44:48.698: %LINK-3-UPDOWN: Interface GigabitEthernet0/0/0, changed state to down
*Apr 14 17:44:51.994: %LINK-3-UPDOWN: Interface Gi

Mark Malone · ‎04-15-2019

is this the interface connected to the modem , is it flapping all the time ?
%LINK-3-UPDOWN: Interface GigabitEthernet0/0, changed state to up

can you post output ---- show interface g0/0/0

Richard Burts · ‎04-15-2019

The original post tells us that the connection to ISP is through vlan 1

My Cisco router 2900 connected via interface vlan1 to ISP modem

We do not have enough information about this situation to be able to give good advice. An explanation of the topology would be a good starting point. Seeing the configuration would be helpful. And the output of show ip interface brief and of show ip route would also be helpful.

HTH

Rick

HTH

Rick