CRC Errors & Interface Bounce

[WGL_BK]

Hello all. I've got a 2960x powering an AP and I've seen multiple logs on the switch saying that a particular interface went down and then back up for a couple seconds, some minutes at times. It's probably not an issue but I'm not liking the log being there without confirming it's something insignificant.

Nov  6 14:41:21: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/18, changed state to down
Nov  6 14:41:22: %LINK-3-UPDOWN: Interface GigabitEthernet1/0/18, changed state to down
Nov  6 14:41:26: %LINK-3-UPDOWN: Interface GigabitEthernet1/0/18, changed state to up
Nov  6 14:41:28: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/18, changed state to up

I've confirmed the following:

Auto duplex - Full on both sides

Auto speed - 1000 Mbps on both sides

TDR test run - All normal, at 60m +/- 10m

The AP doesn't actually go down according the WLC and the AP itself ( uptime is 120 days, 23 hours, 58 minutes)

AIR-AP1562D running 8.8.100.0

I've also seen some CRC errors as seen below. Any ideas on what could be causing this?

GigabitEthernet1/0/18 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is b090.7e7b.1392 (bia b090.7e7b.1392)
  Description: Wireless Access Point
  MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:17, 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: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 2000 bits/sec, 2 packets/sec
  5 minute output rate 37000 bits/sec, 37 packets/sec
     35630516 packets input, 10183417526 bytes, 0 no buffer
     Received 3063020 broadcasts (3028575 multicasts)
     945 runts, 0 giants, 0 throttles
     3675 input errors, 2659 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 3028575 multicast, 0 pause input
     0 input packets with dribble condition detected
     1243524852 packets output, 180837570034 bytes, 0 underruns
     0 output errors, 0 collisions, 1 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

[Reza Sharifi]

Hi,

There are also some input errors as well as some runts. Have you tried replacing the copper cable? Is that a cat6 or 6a?

HTH

[WGL_BK]

Hello Reza,

This is a CAT 6 STP run - replacement would be the last resort since it's not an easy run.

[Leo Laohoo]

8.8.100.0 -- Yeah, I've used this particular version. 

All I am going to say is this:  Upgrade the firmware of the controller to something more recent.  

[WGL_BK]

Thanks for the feedback, Leo. That bad, huh? I'd have a hard time convincing higher ups to upgrade without some really clear problems caused by the firmware, unfortunately. I've wanted to. May I ask what kind of experience did you have with it?

[Leo Laohoo]

We have two sets of WLC in an HA.  I also have two WLC in stand-alone.  All four are running 8.8.125.0. 

One of the quirks with 8.8.125.0 involves controllers in HA.  I have to reboot them every 32 days because the the controllers would start dropping/discarding DTLS.  All day long I'll see APs leaving the controllers and come back.  

The controllers in stand-alone does not have this issue.   

The firmware you're running is "MR0" -- That is version 0.  Upgrade to something more recent and the see if the issue still persist.  

[WGL_BK]

Ah, I see. Thanks. 

I've been looking at the open caveats for 8.10.130.0 and I saw some that might affect me including this one: https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvu83242

It says the fixes are included in below list - two questions, 1. are the ap-XXXXX releases for standalone APs? 2. the available versions for 8.10 are 8.10.130.0 and 8.10.142.0, so what does 8.10(139.44) below refer to?

Known Fixed Releases:	(6)
ap-17.5.0.11
ap-17.4.0.130
ap-17.3.2.19
AP.CI.3798
AP.CI.11.4.2.14
8.10(139.44)

[Leo Laohoo]

Raise a TAC Case and ask them to verify if this is fixed in the newly-released 8.10.142.0 or not.

Release Notes for Cisco Wireless Controllers and Lightweight Access Points, Cisco Wireless Release 8.10.142.0