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New Member

Hosts hard-set to 100Full and connected to 79xx PC Port (default is Auto)

Hi there,

Just wondering if anyone in the field has come across the situation where all hosts on a network are hard-set at 100Mbps, Full Duplex? I am about to roll out a 400 phone/host network, with PCs connecting to the PC port on the 79xx. This presents a lot of work from either angle - setting all hosts back to auto, or setting all phones to 100Full.

I have tested connecting a host hard set at 100Full to the PC port on a 7940/7960 set for auto, and the approproate problems exist - poor performance, as PC Port on 79xx is 100Half, and the PC NIC is at 100Full.

Problem is - I can' t see a way to set a phone at 100Full in CallManager - it needs to be done at the phone.

Is there some magical setting that I am overlooking that enables the PC port to be automatically configured for 100Full when registering with the CallManager?

(PS: Running 3.1.4b ServicePack C)



New Member

Re: Hosts hard-set to 100Full and connected to 79xx PC Port (def

By default IP phones are in auto negotitation mode. And you cant change the setting of this RJ-45 port in IP phone. If you configure the PC also for autonegotiation both will configure for the higher speed of 100 mbps full duplex.

If you hardcore the PC for 100 mpbs that is instead of Auto negotiation the IP phone is no longer able to negotiate and will be impossible to negotiate. the negotiation depends on the duplex mode, if it is hardcored or not.

So configure the PC side for auto negottitation and your IP phone will be automatically negotitaed for full duplex 100 mbps

And also the same for the other port which connects to the Switch to get registered with the Call manager.

To set the port speed in a catalyst switch refer the following URL

Configuring and Troubleshooting Ethernet 10/100/1000Mb Half/Full Duplex Auto-Negotiation

Cisco Employee

Re: Hosts hard-set to 100Full and connected to 79xx PC Port (def

There is no easy way to do this for multiple phones, but here are the directions:

1) Press the setting Button

2) **#* --- This unlocks the settings

3) Select network Configurations

4) Go to Option 41 or press 41 quickly on the phone and it will go straight there.

5) Press the Edit Soft Key

6) Now enter any of the following using the numeric key pad

A=Auto, 10h=10mb half-duplex, 10f=10mb full-duplex, 100h=100mb half-duplex, 100F=100mb full-duplex.

7) select the validate soft key and current PC port configuration will change to what ever you choose to set.

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