05-15-2008 12:11 PM - edited 03-05-2019 11:01 PM
Anyone else having problems with DHCP snooping on 12.2(44)SE2? Seems to work fine on a 3550 but shuts down all dhcp (without saying it is dropping any packets) in a 3560-48-PS.
I'm interested to know if anyone else can verify this malfunction.
05-16-2008 02:07 AM
I have had the same DHCP snooping configuration for a while and have had no problems moving from IOS 12.2(35)SE through to the latest 12.2(44)SE2. Are you sure you have trust configured on your uplinks and/or the interface where the DHCP server is?
It might be worth posting some bits of the config.
Andy
05-16-2008 05:54 AM
Yeah I'm sure of that, first thing I checked.
It kills DHCP entirely, not just on snooped VLANs.
I'm working up a stripped down config on a test switch now and will post that.
In the meantime, what platforms are you running it on -- as I said it seems to work fine on the 3550 EMI chassis I have, but not on a 3560 PoE switch, and now that I've started testing, not on a 2960G.
05-16-2008 06:10 AM
I have 3550's, 3560's & a 3750, all of which are running 12.2(44)SE2 and DHCP snooping is running fine on all of them.
Andy
05-16-2008 06:21 AM
Have you disabled option 82 insertion? If your DHCP server is Windows 2000/2003 then you need to disable this in global config:
no ip dhcp snooping information option
Apparently Windows 2008 DHCP will support this but nothing earlier.
Andy
05-16-2008 06:45 AM
OK, nevermind it wasn't the platform. It seems the problem is that if you are using scp:// for the database and the startup transfer fails, it hoses the DHCP snooping system entirely and probably cannot be fixed without a reboot.
Which is probably realted to the fact that you have to init dhcp snooping with a tftp:// database before you can even run an scp:// database.
I'm gonna go bug TAC on this one.
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