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IP Phone 7945 not passing vlan to PC

Hello.  Last Friday, for some reason, two IP Phone 7945's stopped forwarding VLAN IP's to PC's connected to it.  Here's what we got:  We have a Cisco 3750 with ports set up for VLAN 7 for IP Phones and VLAN 25 for Windows PC's.  There are two IP Phones connected to this switch, each IP Phone has a PC daisy changed through it.  For some reason, last Friday morning, the PC's lost connectivity, while the phones were working normally (can send/receive calls).  I connected the PC's straight to two separate ports on the switch.  That made the PC's work again!  I connected my laptop to the phone, and I couldn't get an IP address from their either.

What could be wrong with thw switch?  As far as I know, no one made any configuration change on the switch.

Thanks in advance for your help.


IP Phone 7945 not passing vlan to PC

Hi mlewis, can you verify the phone data port is still enabled and also share the 3750 port config? Is it possible the phone port MAC limit changed on the switch?

Please mark answered for helpful posts

-Tom Please mark answered for helpful posts