High cpu with dhcp snooping

[rop]

Hi all,

I am using 2950T and have configured dhcp snooping with this config:

conf t

ip dhcp snooping

ip dhcp snooping vlan 416

int range fa0/1 - 24

ip dhcp snooping limit rate 50

int gig0/1 (Uplink)

ip dhcp snooping trust

int gig0/2

ip dhcp snooping trust (uplink)

After this the 2950 goes up to 80% cpu, and is barely accessible.

Have i done something wrong, or will the cpu return to 20%?

//Robert Pettersson

senior network engineer, WetterNet

[Mikhail.Galiulin]

Hej Robert,

I would recommend you to upgrade the software on the switch if it is not already the latest version. Otherwise the configuration seems to be correct.

//Mikhail Galiulin

[rop]

Hi,

have upgraded to "c2950-i6q4l2-mz.121-22.EA8a.bin" and there is still no change in cpu-load.

[Mikhail.Galiulin]

Well,

In Cisco Bug Toolkit there are couple of articles which looks similar to yours.

The first thing to check now is the option-82. It is enabled by default so would be interesting to see what's happen if you disable it.

Otherwise it would be better if you can open case at Cisco because it could be that your problem depends on some other features enabled on the switch.

//Mikhail Galiulin