DHCP Snooping Setup

[mumer2]

Dear Team.
I am stuck in DHCP snooping scenario. As i use to enable DHCP-Snooping on the switches, the PABX stops to give ip addresses to the IP phones.
PABX is connected with Server farm switch with VLAN 20 for voice. I enabled VLAN base DHCP-snooping on this switch and trusted the port on which the PABX is connected (1/1/10). Configuration on server switch for DHCP-Snooping as per below:

vlan 20 members port 1/1/10 untagged
dhcp-snooping vlan 20 admin-state enable
dhcp-snooping binding admin-state disable
dhcp-snooping linkagg 1 trust

Core Switch Configuration:
dhcp-snooping vlan 20 admin-state enable
dhcp-snooping binding admin-state disable
dhcp-snooping linkagg 1 trust \\connected to server switch


Distribution Switch Configuration
dhcp-snooping vlan 20 admin-state enable
dhcp-snooping binding admin-state disable
dhcp-snooping linkagg 1 trust \\connected to Core switch switch

Access Switch Configuration
dhcp-snooping vlan 20 admin-state enable
dhcp-snooping binding admin-state disable
dhcp-snooping linkagg 1 trust \\connected to Distribution switch switch

Guide me where i did mistake in the configuration or how can i more secure the LAN network with L2 DCHP-Snooping configuration.

PABX (1/1/20) --- Server Switch (0/1) --- Core Switch (0/1) Distribution Switch --- (0/1) Access switch (1/1/1 -10) Ip Phones

I had attached the diagram for your further reference so it would be easy for you guys to give me a suitable solution.

[Cristek]

Hi!
Your diagram is missing, but from the information you posted, it looks like you are missing dhcp-snooping port 1/1/10 trust on the server switch

[mumer2]

Hi,
Sorry for that.
I had configured port trust on Server Farm switch. but still facing the issue.

Is the configuration fine that i had done.
Do i need to configure DAI also along with DHCP-Snooping.

[Cristek]

Then try re-enabling the binding table on all switches. I never disable it when I implement dhcp-snooping (it's on by default I believe).