SRX

I have vlan.0 (192.168.2.0/24) and vlan.20 (192.168.20.1). Polycom VOIP phones boot up in vlan.0, then inspect dhcp option 128 to get their vlan id (20). The phone then drops the vlan.0 ip address and re-boots with DHCP server address 192.168.20.1.

The SRX dhcp server at 192.168.20.1 can be pinged from the 192.168.2.0/24 subnet, but the phones are unable to get an IP address in the 192.168.20.0/24 subnet. I think the problem might be the propagate-settings interface, but I'm too new at this to know for sure.

# show | match 192.168.20. | display set
set system services dhcp router 192.168.20.1
set system services dhcp pool 192.168.20.0/24 address-range low 192.168.20.2
set system services dhcp pool 192.168.20.0/24 address-range high 192.168.20.254
set system services dhcp pool 192.168.20.0/24 router 192.168.20.1
set system services dhcp pool 192.168.20.0/24 propagate-settings vlan.20
set interfaces vlan unit 20 family inet address 192.168.20.1/24

Hello Mike 

I see that the issue is with phones sending dhcp request to vlan.0 but the dhcp server is configured on vlan.20.

Try configuring vlan.0 as a relay and point the dhcp server ip to vlan.20 Ip.

For configuring dhcp relay use : 

http://kb.juniper.net/InfoCenter/index?page=content&id=KB15755

Rgerads,

c_r

Please Mark My Solution Accepted if
it Helped, Kudos are Appreciated too

I was able to resolve my own issue. Polycom Soundpoint IP phones will automatically look in DHCP option 128 for vlan assignment. I added option 128 to my DHCP config and that took care of that. The phones were unable to get an IP address in the voice vlan. The last problem was that the Dell switch ports needed to be configured to tag packets in the voice vlan.

There were multiple steps to resolve the issue:

1. create a voice vlan
2. create dhcp in the voice vlan
3. put the voice vlan in the trust zone.
4. add dhcp option 128 to my DHCP server in the data vlan
5. tag the ports in the switches for the voice vlan

Thanks, Mike