Stack of five C3750 switches running 12.2(25)SEB4.
Security features on the port are:
port-security (restrict 3 mac)
DHCP snooping (with dhcp pool on the switch)
Dynamic ARP Inspection/DAI
As reccommended in the config guide.
The problem is upon reload, albeit cold start or warm start, the CPU runs at 100%. The process that is reporting the problems is Logger initially:
-show proc cpu
CPU utilization for five seconds: 100%/1%; one minute: 94%; five minutes: 51%
24 189319 184 1028907 69.76% 69.47% 35.80% 0 Logger
%SYS-3-CPUHOG: Task is running for (2098)msecs, more than (2000)msecs (2/1),process = Logger
When I turn off logging, I can then see the DAI process as the cause by issuing a show proc cpu again:
121 726073 6256 116060 88.15% 87.78% 77.38% 0 HRPC dai request
It took 25 minutes for a nearly fully populated stack of 5xC3750-48 switch with 7940's and PC's, to stabilise. Phones slowly started to load and the CPU suddenly drops to 30% and then to its normal 10%:
CPU utilization for five seconds: 100%/1%; one minute: 94%; five minutes: 51%
This is bad enough and it looks like a problem with the DAI process. But the odd thing is that in the lab I have recreated this problem and the resolution doesnt seem to be turning of DAI, but turning off port security?!?!? Even though port security isnt listed as a problem process.
Yet another 3750 bug?
