SG300 won't insert option82 during DHCP relay

[Jonathan Fisher]

Hey guys, anyone having trouble getting an SG300 series switch to insert option82 information? I have DHCP relay working successfully between two VLANs, however, I would like to identify where the client is connected in order to set their routing preferences optimally.

switch-20-0#show ip dhcp relay 
DHCP relay is Enabled
Option 82 is Enabled
Maximum number of supported VLANs without IP Address is 256
Number of DHCP Relays enabled on VLANs without IP Address is 1
DHCP relay is not configured on any port.
DHCP relay is enabled on Vlans: 20
Active: 20
Inactive: 
Servers: 192.168.0.2 

       I have to missing something simple. Any help, or even "hey did you try" type answers very much appreciated!

[paolo bevilacqua]

Wrong forum, post in 'small business switches'. You can move your post using the actions panel on the right.

[trgood · Accepted solution]

Hi Jonathan,

To my knowledge you have everything configured correctly. I would try to setting up packet captures on the switch on the interface heading to the DHCP server to see if the information is included on the DHCP Discover message. 

-Trent Good

** Please rate useful posts! **

[Jonathan Fisher]

http://www.cloudshark.org/captures/f1dbc2e0e9a6

I had already done this at some point, but I tried again this morning after a cup of coffee. At some point this started working!

Now I just need Dnsmasq to recognize this info!