Re: Cisco APs Randomly Reboots - Page 2

B A · ‎10-15-2019

Hello.

This is what happens. Recently we replaced and connected 45 new AIR-AP1852I-E-K9 APs to non-PoE switches. However, we used TP-Link Power adapter to power all APs so WLC showed "PoE/Medium Power". To solve this we bought Cisco PWRINJ6 power injectors and replaced all TP-Links and as a result, WLC showed "Power Injector/Full Power". All radios were fully working and we were satisfied.

However, since that time three access points randomly reboot (3-5 times a day) and after a reboot they switch from "Full Power" to "Medium Power". There is no patter when they reboot. All 45 APs have the same firmware version.

What we did: we changed a power cable to an injector, we changed the injector twice, we changed a patch cord between the injector and a switch, we used a different port on a switch, we tested the cable between the AP and the injector... all is ok, we checked the configuration of these APs on WLC, we also changed the AP. But still no joy. No matter what we change, three APs reboot.

1. Why just three APs reboot? 2. Why do they switch to Medium Power?

Any Cisco expert here?

Thanks for any help.

Leo Laohoo · ‎10-22-2019

Actually, post the complete output to the command "sh flash syslog".

B A · ‎10-23-2019

Here is the output you wanted.

AP#sh flash syslogs
Directory of /storage/syslogs/
total 284
-rw-r--r-- 1 root root 19151 Oct 22 10:41 64
-rw-r--r-- 1 root root 5454 Oct 22 10:41 64.last_write
-rw-r--r-- 1 root root 970 Oct 22 10:33 64.modlog
-rw-r--r-- 1 root root 20438 Oct 22 10:34 64.start
-rw-r--r-- 1 root root 24 Oct 22 10:41 64.watchdog_status
-rw-r--r-- 1 root root 7822 Oct 22 11:37 65
-rw-r--r-- 1 root root 20451 Oct 22 11:36 65.0
-rw-r--r-- 1 root root 5569 Oct 22 11:37 65.last_write
-rw-r--r-- 1 root root 970 Oct 22 10:41 65.modlog
-rw-r--r-- 1 root root 20424 Oct 22 10:41 65.start
-rw-r--r-- 1 root root 24 Oct 22 11:37 65.watchdog_status
-rw-r--r-- 1 root root 503 Oct 22 12:29 66
-rw-r--r-- 1 root root 20425 Oct 22 11:55 66.0
-rw-r--r-- 1 root root 5531 Oct 22 12:29 66.last_write
-rw-r--r-- 1 root root 970 Oct 22 11:37 66.modlog
-rw-r--r-- 1 root root 20438 Oct 22 11:38 66.start
-rw-r--r-- 1 root root 24 Oct 22 12:29 66.watchdog_status
-rw-r--r-- 1 root root 15609 Oct 22 22:52 67
-rw-r--r-- 1 root root 4998 Oct 23 02:44 67.last_write
-rw-r--r-- 1 root root 970 Oct 22 12:29 67.modlog
-rw-r--r-- 1 root root 20438 Oct 22 12:29 67.start
-rw-r--r-- 1 root root 241 Oct 23 05:15 68
-rw-r--r-- 1 root root 20480 Oct 23 05:15 68.0
-rw-r--r-- 1 root root 4998 Oct 23 07:27 68.last_write
-rw-r--r-- 1 root root 970 Oct 22 12:29 68.modlog
-rw-r--r-- 1 root root 20438 Oct 22 12:29 68.start
---------------------------------------------------------------------------
Filesystem Size Used Available Use% Mounted on
flash 57.6M 240.0K 54.4M 0% /storage

Leo Laohoo · ‎10-23-2019

Can you download the following files: 66.last_write, 66.watchdog_status and 66.start

B A · ‎10-23-2019

Here you are...

Leo Laohoo · ‎10-23-2019

Oct	22	10:33	64.modlog
Oct	22	10:34	64.start
Oct	22	10:41	64
Oct	22	10:41	64.last_write
Oct	22	10:41	64.watchdog_status
Oct	22	10:41	65.modlog
Oct	22	10:41	65.start
Oct	22	11:36	65
Oct	22	11:37	65
Oct	22	11:37	65.last_write
Oct	22	11:37	65.watchdog_status
Oct	22	11:37	66.modlog
Oct	22	11:38	66.start
Oct	22	11:55	66
Oct	22	12:29	66
Oct	22	12:29	66.last_write
Oct	22	12:29	66.watchdog_status
Oct	22	12:29	67.modlog
Oct	22	12:29	67.start
Oct	22	12:29	68.modlog
Oct	22	12:29	68.start
Oct	22	22:52	67
Oct	23	2:44	67.last_write
Oct	23	5:15	68
Oct	23	5:15	68
Oct	23	7:27	68.last_write

I've arranged the output to the command "sh flash syslog" in hierarchical order based on time and date.

The files that I've requested didn't contain much information as to the cause of the AP rebooting. The AP didn't crash.

Lack of information means that the AP rebooted potentially due to faulty cabling.

B A · ‎10-23-2019

Thank you. Which cabling do you mean? Still I do think that the cabling is ok. As I said in previous posts, the infrastructure works great with different power injectors. When I use PWRINJ6, the issue starts.

Also I am not sure if your conclusion is relevant due the fact it was me rebooting the AP at all times except 2:44 (Oct 22). However, this AP reboots daily so I can provide the output tomorrow and hopefully you will get more relevant information.

Anyway, here is the output from another AP. This AP auto-rebooted at 9:23 (Oct 18) and 4:31 (Oct 21)

AP2#sh flash sys
Directory of /storage/syslogs/
total 252
-rw-r--r-- 1 root root 15158 Oct 16 08:03 43
-rw-r--r-- 1 root root 4998 Oct 16 13:28 43.last_write
-rw-r--r-- 1 root root 970 Oct 16 07:59 43.modlog
-rw-r--r-- 1 root root 20438 Oct 16 08:00 43.start
-rw-r--r-- 1 root root 16925 Oct 17 15:02 44
-rw-r--r-- 1 root root 5005 Oct 18 09:23 44.last_write
-rw-r--r-- 1 root root 970 Oct 16 07:59 44.modlog
-rw-r--r-- 1 root root 20424 Oct 16 08:00 44.start
-rw-r--r-- 1 root root 14469 Oct 18 14:03 45
-rw-r--r-- 1 root root 4998 Oct 19 04:47 45.last_write
-rw-r--r-- 1 root root 970 Oct 16 07:59 45.modlog
-rw-r--r-- 1 root root 20438 Oct 16 08:00 45.start
-rw-r--r-- 1 root root 14226 Oct 19 10:27 46
-rw-r--r-- 1 root root 5005 Oct 21 04:31 46.last_write
-rw-r--r-- 1 root root 970 Oct 16 07:59 46.modlog
-rw-r--r-- 1 root root 20424 Oct 16 08:00 46.start
-rw-r--r-- 1 root root 3770 Oct 23 10:55 47
-rw-r--r-- 1 root root 20462 Oct 21 12:58 47.0
-rw-r--r-- 1 root root 5006 Oct 23 11:06 47.last_write
-rw-r--r-- 1 root root 970 Oct 16 07:59 47.modlog
-rw-r--r-- 1 root root 20424 Oct 16 08:00 47.start
---------------------------------------------------------------------------
Filesystem Size Used Available Use% Mounted on
flash 57.6M 292.0K 54.3M 1% /storage

B A · ‎10-23-2019

Well, the first AP rebooted twice cca at 12:18 and 12:29. I am enclosing four files as marked in the log.

This is the output:

AP#show flash sys
Directory of /storage/syslogs/
total 268
-rw-r--r-- 1 root root 503 Oct 22 12:29 66
-rw-r--r-- 1 root root 20425 Oct 22 11:55 66.0
-rw-r--r-- 1 root root 5531 Oct 22 12:29 66.last_write
-rw-r--r-- 1 root root 970 Oct 22 11:37 66.modlog
-rw-r--r-- 1 root root 20438 Oct 22 11:38 66.start
-rw-r--r-- 1 root root 24 Oct 22 12:29 66.watchdog_status
-rw-r--r-- 1 root root 15609 Oct 22 22:52 67
-rw-r--r-- 1 root root 4998 Oct 23 02:44 67.last_write
-rw-r--r-- 1 root root 970 Oct 22 12:29 67.modlog
-rw-r--r-- 1 root root 20438 Oct 22 12:29 67.start
-rw-r--r-- 1 root root 894 Oct 23 11:29 68
-rw-r--r-- 1 root root 20480 Oct 23 05:15 68.0
-rw-r--r-- 1 root root 4998 Oct 23 12:16 68.last_write
-rw-r--r-- 1 root root 970 Oct 22 12:29 68.modlog
-rw-r--r-- 1 root root 20438 Oct 22 12:29 68.start
-rw-r--r-- 1 root root 19581 Oct 23 12:20 69
-rw-r--r-- 1 root root 4998 Oct 23 12:27 69.last_write
-rw-r--r-- 1 root root 970 Oct 22 12:29 69.modlog
-rw-r--r-- 1 root root 20424 Oct 22 12:29 69.start
-rw-r--r-- 1 root root 19581 Oct 23 12:31 70
-rw-r--r-- 1 root root 4999 Oct 23 13:19 70.last_write
-rw-r--r-- 1 root root 970 Oct 22 12:29 70.modlog
-rw-r--r-- 1 root root 20424 Oct 22 12:29 70.start
---------------------------------------------------------------------------
Filesystem Size Used Available Use% Mounted on
flash 57.6M 232.0K 54.4M 0% /storage

Leo Laohoo · ‎10-23-2019

@B A wrote:

Oct 23 12:20:16 brain: LLDP PoE negotiation FAILED !!

I've seen this error message before. What power injector is the AP connected to? Not the PWRINJ6, is it?

B A · ‎10-23-2019

There is an AIR-PWRINJ6 injector.

We also tried to use another two AIR-PWRINJ6 injectors but no luck. The AP still reboots and gets Medium Power.

Leo Laohoo · ‎10-23-2019

The way I see it the AP is not crashing.
The only cause of the AP to reboot at various times is when the cable, going from the injector to the AP, is faulty.
TDR won't do any help because the pins of the cable doesn't come "off" very often enough to be detected by TDR.

B A · ‎10-23-2019

Thank you. However, this happens at three places so we have suddenly three bad cables? Also as I wrote before, any other power injector works there which is quite weird. I mean how is it possible that the cable is ok for three types of power injectors and faulty just for PWRINJ6? That's why I am not sure what you think. Is there anything else that comes to your mind? Thank you for your help.

Leo Laohoo · ‎10-24-2019

That's one thing I don't like about injectors is that they don't leave "traces".
If this is happening to three places then the injectors could be faulty.
I'm no sparky so I can't say for certain.

B A · ‎10-24-2019

I understand. However, injectors are 100% ok. If I move them to another place, they work as supposed. I am lost now.

B A · ‎10-29-2019

Does it have a solution?

osonuwechris · ‎10-22-2019

Please can I get ios for wireless controller