The CAPWAP dead neighbor interval elapsed during the previous CAPWAP session

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Hi all

Why does this happen?

Is it because of a bad cable?
Suddenly the AP shuts down for 5 min, because the AP does not respond to this CAPWAP session.

I accept that, but i have no clue why it cannot keep connected to the HM?

How do i test what is wrong?
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Mike Tulin Holmgaard Kristensen

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Posted 2 years ago

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Luke Harris

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The dead neighbor interval is the length of time that the CAPWAP server and client wait for responses to their echo requests before determining that their neighbor is dead—that is, that the neighbor is no longer responding—and that it is safe to close the CAPWAP connection to that neighbor. 

When a CAPWAP server sends an echo request to a client, a response is naturally expected. If a response is not received within the dead neighbor interval, then the CAPWAP connection is considered lost and is closed. 

The default neighbor dead interval is 105 seconds, but you can change this value at the CLI by using the following command: 

capwap client neighbor dead interval 

Where the interval in seconds and a value from 60 to 240.

You need to perform some physical checks as well as check your switching infrastructure for errors. It may be worth using something like Wireshark on your management VLAN to see what traffic is on that segment. 
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Mike Kouri, Official Rep

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Loss of connectivity to the central management platform should NOT affect forwarding of user traffic across the access point. If you are seeing it become non-responsive for 5 minutes, it sounds to me like you are observing it reboot. The suggestion to check the logs was a good one.
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Mike Tulin Holmgaard Kristensen

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Same AP gives me these ALARMS today.

I got 3 AP's on a 10/100 switch. Together 110 devices are sometimes connected.

The switch says POE MAX (red flash alarm). I got no other switch to test with, if the POE is the problem. could it be?

Also, is 10/100 switch and old sad 30 meters non outside used outside cable a reason for this? The students are often connecting at the same time, and often working with youtube and stuff.

Should i go for gigabit swith with enough POE power and pull a new 30 meters gigabit cable?