Certain IP phones have different DHCP server

[stevegrosz]

In our phone systems, it appears that the phones are assigned to a DHCP that is one of the phone vlans.  For some reason 2 of our phones have been set in the network configuration on the phone to the DHCP server for our computers.

How can I get into the phone and set them to the correct DHCP server?  There is a "lock" indictator on the phone if I press the **# and settting button, so I can't make any changes to the configuration on the phone.

Is there another way to change them?

[paolo bevilacqua]

Check/fix configuration of the switch port to which they are connected, then remotely reset the phone.

[stevegrosz]

Wouldn't that mean the phone wouldn't be working at all?  It is in these cases........ just curious, but I can reset the phones.......

[paolo bevilacqua]

No, it would just take address from another vlan, and that's it.

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[stevegrosz]

Well I did a factory reset on the phone, and it still pulls up the wrong DHCP host........

[paolo bevilacqua · Accepted solution]

Check switch port configuration.

[Jayant Kohli]

Hey Steve,

I was wondering if you tried plugging in a different phone to these ports or plugging these phones somewhere else to further break down the issue...

Also, what is the IP address they receive when we look at the CM device configuration page?

Is there any firmware difference between the working and non working phones?

We might have to look at the sniffer later on to see what configuration a phone pulls when it gets registered.

Please keep me updated as its an interesting one...

Regards

Jayant

[Allan Perocho]

You may check the switchport voice vlan "vlanid" on the switch port configuration on which the ip phone is connected. If you can not unlock the ip phone by pressing **#, you need to ENABLE the Setting Access in IP phone device configuration in CCM.

Hope it helps.

[stevegrosz]

It did end up being that the ports in question weren't assigned to the vlan.  Once the vlan and trunk was set up, and the phones were rebooted, the correct settings showed up.

Thanks very much!!