Re: [c-nsp] DHCP relay still forwarding to old helper even if it's removed or changed
On Mon, 2015-01-19 at 21:18 +0200, Tarko Tikan wrote: I tried to change the helper address, but after making the change, the box was still routing broadcasts to the old helper. Are you 100% sure it's actually relayed traffic and not DHCP client that remembers DHCP server address and unicasts the request? On Mon, 2015-01-19 at 19:20 -0500, Jason Lixfeld wrote: The lease timer is 3 minutes, so if after 4 minutes it’s still trying to reach the old server, it shouldn’t be a client-side problem. That said, I’ll reboot a client tomorrow and see what happens. As long as the client can actually renew the lease it will continue to unicast requests to the old server. So unless the scope is disabled on the old server (making it reply with NAKs or not reply) they will not move to the new server. Are you actually seeing DISCOVERs on the old server? Or just REQUESTs? (Takes a server that actually logs this to find out of course.) -- Peter ___ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
Re: [c-nsp] DHCP relay still forwarding to old helper even if it's removed or changed
The lease timer is 3 minutes, so if after 4 minutes it’s still trying to reach the old server, it shouldn’t be a client-side problem. That said, I’ll reboot a client tomorrow and see what happens. On Jan 19, 2015, at 2:18 PM, Tarko Tikan ta...@lanparty.ee wrote: hey, I tried to change the helper address, but after making the change, the box was still routing broadcasts to the old helper. Are you 100% sure it's actually relayed traffic and not DHCP client that remembers DHCP server address and unicasts the request? -- tarko ___ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ ___ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
[c-nsp] DHCP relay still forwarding to old helper even if it's removed or changed
I’ve got a 4500/Sup7L-E running 3.3.2SG (15.1(1)SG2) with an SVI configured to use a DHCP relay (ip helper-address). I tried to change the helper address, but after making the change, the box was still routing broadcasts to the old helper. I’ve seen this once before and did a bunch of troubleshooting, but couldn’t find a workaround short of rebooting the box. I went so far as to try and delete and recreate the SVI with the interesting helper config on it, but even still, it sends to the original helper address. Has anyone seen anything like this in the wild before? I know this is running really old code and I have a plan in the works to upgrade all the boxes running this version to 3.6E where this and a bunch of other bugs are fixed, but I’m hoping that I can effect some sort of a workaround for this particular issue until then. Thanks in advance. ___ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
Re: [c-nsp] DHCP relay still forwarding to old helper even if it's removed or changed
Thanks for the suggestion, Chuck. Sadly, no dice. I’m still see DHCP packets to the previously configured helper. On Jan 19, 2015, at 1:49 PM, Church, Charles charles.dav.chu...@hp.com wrote: Maybe try 'no service dhcp' and then put it back in to restart the process? Chuck Sent from my Verizon Wireless Galaxy S4 Original message From: Jason Lixfeld Date:01/19/2015 1:10 PM (GMT-05:00) To: c-nsp Subject: [c-nsp] DHCP relay still forwarding to old helper even if it's removed or changed I’ve got a 4500/Sup7L-E running 3.3.2SG (15.1(1)SG2) with an SVI configured to use a DHCP relay (ip helper-address). I tried to change the helper address, but after making the change, the box was still routing broadcasts to the old helper. I’ve seen this once before and did a bunch of troubleshooting, but couldn’t find a workaround short of rebooting the box. I went so far as to try and delete and recreate the SVI with the interesting helper config on it, but even still, it sends to the original helper address. Has anyone seen anything like this in the wild before? I know this is running really old code and I have a plan in the works to upgrade all the boxes running this version to 3.6E where this and a bunch of other bugs are fixed, but I’m hoping that I can effect some sort of a workaround for this particular issue until then. Thanks in advance. ___ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ ___ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
Re: [c-nsp] DHCP relay still forwarding to old helper even if it's removed or changed
hey, I tried to change the helper address, but after making the change, the box was still routing broadcasts to the old helper. Are you 100% sure it's actually relayed traffic and not DHCP client that remembers DHCP server address and unicasts the request? -- tarko ___ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
