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New Member

Duplex mismatch between SW and IP phones

I saw a lot of posta about duplex but I'm still confused...pls help

We have a few thousand 7960 phones set to Duplex and speed Auto/Auto by default and our standard switch configuration is 100/Full hardset and not AUTO negotiation (due to historical issues with auto nego)

Is there a way to bulk set all my phones to 100/Full? The only way I say is to do it from the phone manually.

Are there good docs that show that cisco recommends that you set the switch and the phone to AUTO/AUTO....?

I did see this...but this does not seem..proof-worthy

P492

http://www.cisco.com/en/US/docs/voice_ip_comm/uc_system/GB4.3/ipt_na_starm/GP43.pdf

I guess based on 802.3u - setting 100/Full on the switch and Auto/Auto on the phone is a no-no...result is duplex mismatch

I don't know why Cisco doesn't have a way to easily set the phones to 100/full...

thanks in adv

:JoeL

4 REPLIES
New Member

Re: Duplex mismatch between SW and IP phones

The admin guide says "On both the network port and access port, use full-duplex mode to avoid collisions."

didn't understand if it means don't use Auto or just don't use Half-duplex..

Network and Access Ports

The back of the Cisco IP Phones models 7960G and 7940G have two RJ-45 ports labelled 10/100 SW and 10/100 PC. Each port supports 10/100 Mbps half- or full-duplex connections to external devices. You can use either Category 3 or 5 cabling for 10-Mbps connections, but you must use Category 5 for 100 Mbps connections. On both the network port and access port, use full-duplex mode to avoid collisions.

http://www.cisco.com/en/US/docs/voice_ip_comm/cuipph/7960g_7940g/4_1_2/english/administration/guide/7900ins7.html#wp1062797

Also says you can use 100/full on both or Auto on both but does not recommend Auto...##

SW Port Configuration

Speed and duplex of the switch port.

If the phone is connected to a switch, you must configure port on the switch to the same speed/duplex as the phone, or configure both to auto-negotiate.

If you change the setting of this option, you must change the PC Port Configuration option to the same setting.

:JoeL

New Member

Re: Duplex mismatch between SW and IP phones

Hi there,

we are running into same issue for one of the customers. Did you find any bulk tool to do this? or is there any other alternative.

Please let me know.

thanks

Toor

New Member

Re: Duplex mismatch between SW and IP phones

there is no way to do it in bulk...

the best thing is to set the switch to auto/auto

:JoeL

New Member

Re: Duplex mismatch between SW and IP phones

Thanks.

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