My flock of Catalyst 2960X have been increasingly err-disabling ports on account of DHCP Rate Limiting
2020-02-20T05:57:45.184947-08:00 2s-2-esx-mgmt 66380: 066362: 000370: Feb 20 05:
57:44.138 pst: %PM-4-ERR_DISABLE: dhcp-rate-limit error detected on Gi1/0/1, putting Gi1/0/1 in err-disable state (2s-2-esx-1)
The ports which trigger these events typically feed Wireless Access Points -- so the WAP goes down for a few minutes, then returns to life once the switch auto-recovers / re-enables the port
This cycle is disruptive to WiFi service of course, so from a WiFI perspective, I am tempted to disable this feature. On the other hand, from a DHCP server perspective (I run DHCP services on AD Domain Controllers), I'm wary -- if the DCs end up pegging their resources on responding to floods of DHCP Discovers, the knock-on effects might be quite a bit worse.
Anyone else seeing this? What, if anything, are you doing about it?
I have written this up more thoroughly at: https://community.cisco.com/t5/wireless-and-mobility/wifi-clients-issuing-200-dhcp-requets-per-second/td-p/4031516
--sk
