DHCP for IP Phone

My switch has only a port bind to VLAN 6. From there, it attach to PoE system with IP Phones and its system.

For testing, I add one VLAN 6 port and try to see whether there is DHCP service on this VLAN. However, I find that the PC sitting it VLAN6 doesn't get any IP address at all.

How does the IP phone get its IP address ? In case the IP gateway provide the DHCP service, my PC at VLAN 6 should get the IP address. However, it doesn't while the IP handset can.  

I have also attached a DHCP request for a testing workstation in VLAN 6 asking for IP address. It seems that no DHCP server in this VLAN can accept the request. Any idea ?

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Is the voice vlan 6 and the access vlan something else? That would be why the phone can but the PC cannot
AXISHKAuthor Commented:
PC / server in VLAN 3 and Voice in VLAN 6.

For testing, I configure additional port for VLAN 6 (in VLAN as phone system) but no DHCP is leased on PC.

Any further advise ?
Can you share the config on the port?
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AXISHKAuthor Commented:
interface FastEthernet3/0/1
 switchport access vlan 6

Currently,  only port 3/0/1 is assigned to VLAN 6. The port connects to a PoE switch. That is why you can see a set of IP of IP phones are binded to this port.

For testing, I add one more port port 3/0/24 to VLAN 6. Plug in the PC but no IP addresses are leased...
Are you plugging the PC directly into the switch or switch-->phone-->PC?
Also what device is your dhcp server
AXISHKAuthor Commented:
it is NEC ip phone but I do not have the model om hand
Others referenced pointed to it, often there are Mac based determination/vlan assignment which likely means on vlan 6 you gave either the voice system if an ip helper/DHCP relay agent that gets an ip for the phone, on vlan 3 there is no ip helper or the switch port to which the PC connects on a vlan where there is no DHCP.
Test the following, set the PC with a static ip that belongs in vlan 3 and see if it can function.

You switch vlan 3/router for vlan3 need to either have a DHCP server/scope define or have an ip helper/DHCP relay agent defined to forward these requests to the DHCP server where a scope is defined.

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AXISHKAuthor Commented:
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Voice Over IP

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