Eigrp nei flapping

mahesh18 · ‎06-11-2009

Hi all,

We have c2600 router connected by tunnel to main vpn site.

sh log shows

Jun 10 20:27:30 extende: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 22: Neighbor 10.32.29.175 (Tunnel120) is down: Interface Goodbye received

Jun 10 20:27:34 extende: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 22: Neighbor 10.32.29.175 (Tunnel120) is up: new adjacency

Jun 11 00:59:20 extende: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 22: Neighbor 10.32.29.175 (Tunnel120) is down: Interface Goodbye received

Jun 11 00:59:23 extende: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 22: Neighbor 10.32.29.175 (Tunnel120) is up: new adjacency

Jun 11 02:01:56 extende: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 22: Neighbor 10.32.29.175 (Tunnel120) is down: Interface Goodbye received

Jun 11 02:01:59 extende: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 22: Neighbor 10.32.29.175 (Tunnel120) is up: new adjacency

Jun 11 02:07:39 extende: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 22: Neighbor 10.32.29.175 (Tunnel120) is down: Interface Goodbye received

Jun 11 02:07:4

Tunnel120 is up, line protocol is up

Hardware is Tunnel

Description: === IPSEC TUNNEL

Interface is unnumbered. Using address of FastEthernet0/1 (10.251.32.10)

MTU 1514 bytes, BW 1000 Kbit, DLY 500000 usec,

reliability 255/255, txload 5/255, rxload 21/255

Encapsulation TUNNEL, loopback not set

Keepalive not set

Tunnel source 207.229.32.120 (FastEthernet0/0), destination 208.98.244.51

Tunnel protocol/transport GRE/IP

Key disabled, sequencing disabled

Checksumming of packets disabled

Tunnel TTL 255

Fast tunneling enabled

Tunnel transmit bandwidth 8000 (kbps)

Tunnel receive bandwidth 8000 (kbps)

Last input 00:00:00, output 00:00:01, output hang never

Last clearing of "show interface" counters never

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 1

Queueing strategy: fifo

Output queue: 0/0 (size/max)

5 minute input rate 84000 bits/sec, 22 packets/sec

5 minute output rate 23000 bits/sec, 18 packets/sec

9476461 packets input, 204834848 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort

9723521 packets output, 499331584 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 output buffer failures, 0 output buffers swapped out

sh ip eigrp nei

IP-EIGRP neighbors for process 22

H Address Interface Hold Uptime SRTT RTO Q Seq

(sec) (ms) Cnt Num

0 10.32.29.175 Tu120 14 03:11:23 59 354 0 611025

i check the main vpn router where tunnel ends.it shows eigrp nei is stable from last 3 weeks.

any idea why nei is flapping

shivlu jain · ‎06-11-2009

Hi Mahesh

Please check are u able to ping 64 to 1500 bytes end to end. The reason behind this is that eigrp always check the mtu from the above mentioned size. If you are not able to ping then neighborship will flap.

regards

shivlu jain

mahesh18 · ‎06-11-2009

Hi,

thanks for reply

i am able to ping both sides by

64 to 1500 mtu size.

one side has 99% other is 100% success.

thanks

mahesh18 · ‎06-12-2009

Hi have pasted the ping result.

it is still flapping.

telco says allis good from there end.

any idea why this is happening?

thanks

mahesh

Gregory Camp · ‎06-19-2009

What is the IP MTU of the tunnel. You can check this with show ip int Tunnel120. What type of device does this tunnel terminate on, any tunnels on this device or the other that are not flapping?