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IP Phone 7960 connectivity problems

Very odd occurrence...There are over 70 IP Phones at my customer's location and one phone that I am troubleshooting stays stuck on the "Configuring IP" window on the phone. So I took note of the rj45 jack it is plugged and went into the computer room to trace it's port connection into the 6509 switch. I checked the configs and they're fine. So just for sanity check I unplugged the cable and moved it to another open port. Now it works. Any idea why this is happening? I checked the port on the 6509 that was having an issue and it's fine. I guess which debugs can I run to get more details? And what debug information should I look for to pinpoint the source of the problem. Thanks in advance.

Cisco Employee

Re: IP Phone 7960 connectivity problems

The most useful information would come from pluggin a PC running a packet sniffer application like SnifferPro, Network Monitor, or Ethereal into the PC port of the phone and capturing all packets for a few cycles of the phone. Latest versions of ethereal include SCCP decoder so you can read the decoded registration process if interested, otherwise open a TAC case and send the sniffer trace along with the CCM version, the application load running on the phone, and the switch port configuration and we should be able to give good insight to why the phone is not registering. /Wes

Community Member

Re: IP Phone 7960 connectivity problems

Turns out it's has something to do with IP conflicts. The dhcp server is a 3661 router and I discovered there were conflicts for the phone's address. I cleared the conflict and binding for the address then the phone worked after I reset it. I noticed that the lease was set for 14 days. I may shorten that and their scope is large enough for all their phones. Any ideas why the phone would conflict even when unplugging and plugging back in the rj45, because it retains the address it was previously assigned?

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