dhcp for voip phones

[carl_townshend]

Hi all

I was told the other day that there is an option in dhcp server i think its 43, where is gives the ip phone the correct ip address for the vlan, is this correct ?

also how does the switch know that the phone is a tagged packet, does the 802.1p tag sit inside the 802.1q tag ?

[jppdavies999]

Can someone help with a problem I have with siemens SIP phone. Phone works as described earlier in this thread - DHCP request on native vlan and then using option 43 go into IP Telephony Vlan.

the problem:-

if I use a 3750PE and do a trace I can see the DHCP release going back to the DHCP server thus releasing the IP address on the native Vlan.

3750 software - c3750-ipbase-mz.122-35-SE5

If I use a 4503 with 48 port PE card then I dont see the DHCP release. Thus the IP addresses on the native vlan are still on lease and fill up the used IP addresses.

C4503 software - cat4500-ipbase-mz.122-31.SGA8.bin

Same phone, same subnet, just different switch???

Config on both switches is pretty straightforward:-

switchport access vlan 10

switchport voice vlan 52

Ok other enries but I dont see any relevance to this

I have also heard that there is a mechanism with Microsoft DHCP server to regularly ping end points and release if no response. Cant find where this is done - can anyone help??

John Davies South Wales Police

[etmarcof]

Hi Andrew,

I'mt trying to config DHCP option 43 for voice vlan for Ericsson IP Phones (now Aastra)with cisco switches

My DHCP server is cisco switch cat 3750.

What should be phone config file regarding vlan settings?

My Switch port config:

switchport access vlan 20

switchport mode access

switchport voice vlan 10

for example my voice vlan = 10

vlan for PC connected to phone =20

Best regards,

MC

[fab5freddy]

Hi

I also got the requets to configure option 43 for Aastra phones.

Could somebody help me with the hex string?

Following options have to be configured:

Vendor Class = Aamadeus IP Phone):

SIP port pbx: 5060

SIP port phone: 5060

SIP port  backup PABX: 5060

PABX adr=10.5.0.1

Vlan_id=5

Vlan_prio= 6

PABX adr Back Up=10.5.0.2

There is more info in attach" Aastra Phones

The whole manual is als in attach, called "Aastra Aamadeus phone dhcp option 43"

Thanks

Fred

[wpereira]

Hello,

I have the same issue with Aastra phones, the documentation aastra ask me to set up the options 43 and 60, but I dont know how I can do that.

Can anybody help me?

Shoud I set up only that?

option 60 AastraIPPhone6731i

option 60 AastraIPPhone6739i

option 43 number vlan

tks