sundance-communications.com/forum Forums VOIP Phones & IP PBX Networking Mitel DHCP Option Issue

I have client with a DHCP server which offers DHCP for everyone on it's native VLAN. There are Options in his scope to point Mitel Phones to VLAN 2 Priority 6. The phones are suppose to release it's native ip address and then rediscover DHCP on VLAN 2 and obtain an ip address from the Mitel Switch. But that is not happening. It returns with an ip address from the native DHCP server.

Here are some notes about the current situation.


Phones that have been up and functional are working perfectly.

Any phone that gets rebooted will suffer from this issue.

Plugging a Mitel phone directly to the switch, thus isolating the clients network, will boot up with no problems.

The phone switch is plugged into a port on a managed switch.

Here is a copy of a capture he sent me.

No. Time Source Destination Protocol Info
321 64.528840 10.1.1.14 255.255.255.255 DHCP DHCP ACK - Transaction ID 0x1ecd7730

Frame 321 (379 bytes on wire, 379 bytes captured)
Ethernet II, Src: 00:11:09:5f:db:3d, Dst: ff:ff:ff:ff:ff:ff
Internet Protocol, Src Addr: 10.1.1.14 (10.1.1.14), Dst Addr: 255.255.255.255 (255.255.255.255)
User Datagram Protocol, Src Port: bootps (67), Dst Port: bootpc (68)
Bootstrap Protocol
Message type: Boot Reply (2)
Hardware type: Ethernet
Hardware address length: 6
Hops: 0
Transaction ID: 0x1ecd7730
Seconds elapsed: 0
Bootp flags: 0x0000 (Unicast)
Client IP address: 0.0.0.0 (0.0.0.0)
Your (client) IP address: 10.3.1.8 (10.3.1.8)
Next server IP address: 0.0.0.0 (0.0.0.0)
Relay agent IP address: 0.0.0.0 (0.0.0.0)
Client hardware address: 08:00:0f:16:b4:f5
Server host name not given
Boot file name not given
Magic cookie: (OK)
Option 53: DHCP Message Type = DHCP ACK
Option 58: Renewal Time Value = 4 days
Option 59: Rebinding Time Value = 7 days
Option 51: IP Address Lease Time = 8 days
Option 54: Server Identifier = 10.1.1.14
Option 1: Subnet Mask = 255.0.0.0
Option 3: Router = 10.1.1.31
Option 6: Domain Name Server
Option 44: NetBIOS over TCP/IP Name Server = 10.1.1.6
Option 128: Private (4 bytes)
Option 129: Private (4 bytes)
Option 130: Private (15 bytes)
Option 132: Private (4 bytes)
Option 133: Private (4 bytes)
End Option

The client IP Address is what the phone on his desk ends up with after a reboot. The DHCP scope on the mitel is 192.168.1.0

I'm trying not to get into a war with this guy but how do I get him to understand that phones connected directly to the switch boots up and are functional? And that we might need to look into the fact that it may be on his network that is causing the problem?

We might need to look into the fact that it may be on his network that is causing the problem.

What type of switch is the IP phone plugged into? Here is what you need to do. Assign the port as an ACCESS port assign the VLAN you want to the PC to get on that VLAN. Assign either a VOICE vlan or an AUX VLAN to the PC. On the router assign an IP helper on the AUX or voice vlan pointing to the DHCP server.

IE


SWITCH
int fa0/1
switchport mode access
switchport access vlan 3
switchport voice vlan 2

ROUTER
int gi0/0.2
ip address 172.16.2.1 255.255.255.0
encap dot1q 2

int gi0/0.3
ip address 172.16.3.1 255.255.255.0
encap dot1q 3
ip helper-address 172.16.2.20

You could also trunk if you really wanted to. I see know reason for this but here you go.

int fa0/2
switchport mode trunk
switchport trunk native vlan 3
switchport trunk encap dot1q
switchport voice vlan 2

Greg

Assign either a VOICE vlan or an AUX VLAN to the PC.
I meant to say PHONE NOT PC!