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3750 Switch not forwarding DHCP requests 12.2(50) IOS

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

3 REPLIES
New Member

Re: 3750 Switch not forwarding DHCP requests 12.2(50) IOS

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?

New Member

Re: 3750 Switch not forwarding DHCP requests 12.2(50) IOS

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.

Bronze

Re: 3750 Switch not forwarding DHCP requests 12.2(50) IOS

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.

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