3750 Switch not forwarding DHCP requests 12.2(50) IOS

[patel.nishit]

We upgraded our 3750 switch to 12.2(50) version IOS and now are are having issue with switch not forwarding any DHCP request.

Need help

[gthermaenius]

There is a known bug that states that if you are using multicast block feature enabled it also blocks unknown broadcast such as dhcp discovery. Are you using the multicast block feature?

[patel.nishit]

I upgraded from 12.2(44)SE1 because it didn't support the tacacs source interface command. Which is a bug.

But a L3 switch not forwarding DHCP requests is a major problem rather than a bug. The switch is forwarding traffic okay, but the IP helper is failing.

Should the config of a member switch in the stack (rather than master) include

a) IP addresses of the vlans.

b) should the vlan interfaces of the member switch be shutdown.

[iyde]

Go to 12.2(50)SE3 or 12.2(52)SE when it comes out. Reason being memory leak bug if you use http or https to manage switch and also the Cisco Security Advisory: TCP State Manipulation Denial of Service Vulnerabilities in Multiple Cisco Products

Advisory ID: cisco-sa-20090908-tcp24

http://www.cisco.com/warp/public/707/cisco-sa-20090908-tcp24.shtml

HTH.