Help with EIGRP drops

[alliasneo1]

Hi,

I wonder if someone might be able to help me out with an error I keep getting with EIGRP?

We keep getting drops for 1 or 2 minutes several times throughout the day and the only thing that shows up in the logs is:

DUAL-5-NBRCHANGE: EIGRP-IPv4 1 ..... PEER-TERMINATION

DUAL-5-NBRCHANGE: EIGRP-IPv4 1: Neighbor xx.xx.xx.xx (Vlanxxx) is up: new adjacency

[MHM Cisco World]

the VLANxxx is UP DOWN ?
can I see topology 

MHM

[alliasneo1]

It is a single Fibre Connection to a cisco C9500 running at 1gb

Aug 11 07:13:11.704: %DUAL-5-NBRCHANGE: EIGRP-IPv4 1: Neighbor xx.xx.xx.xx (Vlanxx) is up: new adjacency
Aug 11 07:14:11.967: %DUAL-5-NBRCHANGE: EIGRP-IPv4 1: Neighbor xx.xx.xx.xx (Vlanxx) is down: Interface PEER-TERMINATION received

TenGigabitEthernet1/1/1 is up, line protocol is up (connected)
Hardware is Ten Gigabit Ethernet, address is d477.9894.9db5 (bia d477.9894.9db5)
MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 3/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 1000Mb/s, link type is force-up, media type is 1000BaseLX SFP
input flow-control is on, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:12, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 10
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 12074000 bits/sec, 2433 packets/sec
5 minute output rate 7730000 bits/sec, 1607 packets/sec
15336981403 packets input, 13287829757695 bytes, 0 no buffer
Received 4312809 broadcasts (4209172 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 4209172 multicast, 0 pause input
0 input packets with dribble condition detected
9546661948 packets output, 5209906477508 bytes, 0 underruns
Output 1 broadcasts (13703025 multicasts)
0 output errors, 0 collisions, 2 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 pause output
0 output buffer failures, 0 output buffers swapped out

[MHM Cisco World]

two issue 
1- interface have little congestion 

9300(config)#qos queue-softmax-multiplier 1200 <<- need this command 

2- prevent SW drop eigrp when interface congestion 
  ip bandwidth-percent eigrp <<- under VLAN 

MHM

[alliasneo1]

Hi,

Thank you for the response. Would you be able to explain in a little more detail please?

[MHM Cisco World]

https://www.cisco.com/c/en/us/support/docs/switches/catalyst-9300-switch/216236-troubleshoot-output-drops-on-catalyst-90.html

[alliasneo1]

on the monitoring software that we use, I'm not seeing high utilisation for that interface though?

9300(config)#qos queue-softmax-multiplier 1200 <<- need this command 

 For the above command, do I just apply this on the 9300 or on both sides?

2- prevent SW drop eigrp when interface congestion < When you say prevent SW drop, does this mean switch drop?

thanks

[MHM Cisco World]

You have output drop' if each time you do show and yoh see output drop counter increase that meaning you have high utilize in interface.

So interface start drop packet and some of these packet is eigrp hello' 

The other peer will not receive eigrp hello so it declare eigrp peer down.

Check that in peer by check log and using debug ip eigrp hello

MHM

[alliasneo1]

It's a 9300 switch with routing enabled. 1 instance of EIGRP.

Connected to a Cisco C9500 running at 1gb.

TenGigabitEthernet1/1/1 is up, line protocol is up (connected)
Hardware is Ten Gigabit Ethernet, address is d477.9894.9db5 (bia d477.9894.9db5)
MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 3/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 1000Mb/s, link type is force-up, media type is 1000BaseLX SFP
input flow-control is on, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:12, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 10
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 12074000 bits/sec, 2433 packets/sec
5 minute output rate 7730000 bits/sec, 1607 packets/sec
15336981403 packets input, 13287829757695 bytes, 0 no buffer
Received 4312809 broadcasts (4209172 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 4209172 multicast, 0 pause input
0 input packets with dribble condition detected
9546661948 packets output, 5209906477508 bytes, 0 underruns
Output 1 broadcasts (13703025 multicasts)
0 output errors, 0 collisions, 2 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 pause output
0 output buffer failures, 0 output buffers swapped out

[Elliot Dierksen]

I assume you are peering over an SVI (Vlan interface). Is it possible that the MTU is set differently on the devices? MTU mismatch between EIGRP routers will cause the problem you describe.

[David Ruess]

Hello,

First off "Peer termination" means the peer sent the termination so it was having the problem. It's likely it wasn't receiving Hellos from EIGRP neighbor. You may be able to see what happened by issuing the "show ip eigrp events" on the peer having the issue.

Secondly make sure the fiber cable is good. Since fiber uses a cable for transmit and another one for receive one side could be bad. If it's a direct connection clean/replace the fiber connection and make sure the SFPs are seated correctly and not faulty.

You only have 10 interface drops per 2500 packets you're sending and 1500 you're receiving per second which is a very low number and I would not suspect related to your EIGRP drops, but I also wouldn't rule it out.

-David

[Joseph W. Doherty]

---

@David Ruess wrote:

You only have 10 interface drops per 2500 packets you're sending and 1500 you're receiving per second which is a very low number and I would not suspect related to your EIGRP drops, but I also wouldn't rule it out.

---

I too consider 10 drops, if correct, insignificant.  Further, that drop count corresponds with "9,546,661,948 packets output" (also the numbers are since the device booted).  So, it seems unlikely those drops could cause the number of EIGRP events you note per day.

Could you also post the interface stats for the other side of the link?

[paul driver]

Hello
Have you check physical interfaces interconnecting these two eigrp peers ( interface errors,udld,stp etc..)