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New Member

Configuring cisco switch for Siemens voip phones

Hi Everyone

I have a small problem with getting some siemens 40G voip phones to work when connected to cisco 3750's. Basically when I connect the phone will pick up an ip address in the data vlan range and not one in the voice vlan address range. I beleive the siemens phones dont support cdp so I was wondering if anyone has got these phones working with cisco equipment? port config below. Thanks for your help.

interface GigabitEthernet3/0/34

switchport access vlan 10

switchport mode access

switchport voice vlan 20

srr-queue bandwidth share 1 30 35 5

queue-set 2

priority-queue out

mls qos trust dscp

auto qos trust

storm-control broadcast level 10.00

spanning-tree portfast

spanning-tree bpduguard enable

  • IP Telephony
Everyone's tags (5)
New Member

Configuring cisco switch for Siemens voip phones

Ensure LLDP is globaly enabled via the LLDP run command on the 3750 switch and use DLS or the phone web management to ensure LLDP is used to discover the Voice VLAN.

Dont try to do it via DHCP, the Siemens DHCP configuration is an obomination against nature IMHO.