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CISCO 525s stop working after change DHCP Server

This is very odd!!! We change of DHCP Server, keeping the same configuration. We have a mix of Cisco and Polycom phones purchased thru RC and outside. Just 3 phones model 525 stop working, other Cisco 303 and other Polycom keep working fine. Any ideas? (I already talked with two people from Support, no help after several minutes on the line)
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bjsvec avatar image
bjsvec answered ringcentral35 commented
Do those phones pull an IP address?  What exactly is not working about them?

Have you tried restarting switches and routers?  Sometimes when changing a device like that the arp cache or mac address tables still see old mac <> ip relationships and need to be flushed.
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Chuck Fuscone avatar image Chuck Fuscone commented ·
Claudio, I think that the phone is hanging on to the Old IP Address because of the DHCP lease.  Try statically setting an IP address for the phone (From the phone it self) and you should be able to get on.  Not sure how long the lease is that was set but usually a week goes by and the phone should for get it.

I always have my phones statically assigned but I have run in to this issue with a polycom phone in the past

Make Sense??

Chuck
Certified Ring Central Installer
Chuck@yoritguy.com
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ringcentral35 avatar image ringcentral35 commented ·
Thanks. All the lights amber (orange). Can't make calls. Pull IP yes. IP assigned by DHCP service in Windows Server (no router)... Weird: only the Cisco 525.
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bjsvec avatar image bjsvec commented ·
Did you resolve this yet?  Did you try rebooting switches and router? 
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ringcentral35 avatar image ringcentral35 commented ·
No resolved yet, very frustrating!
I moved into a different building (other point of the city), different network to try to isolate the issue... the phone still not working...
Bad coincidence?  Was Cisco doing changes during the weekend ?

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ringcentral35 avatar image ringcentral35 commented ·
Thank Chuck, I already made this step with the static ips... no result.
It is really weird that only the Cisco 525 were affected with the change of DHCP Server.

To make this story even odd, I moved over other building, different network, one of this phones under test still does not work...

Any news with Cisco this last weekend ?  Bad coincidence ?  how can 3 phones fail ?




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ringcentral35 avatar image
ringcentral35 answered
After a couple of days, the problem was solved, some DHCP issues... Thanks so much for giving time sending advices!
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