[Dnsmasq-discuss] Issue with circuit-id matching on dhcp requests

[Max Boon]

Hello,

I have a bunch of switches that have previously been supplied with IP addresses using isc-dhcpd that I am now replacing with dnsmasq. There is an address range for automatically assigned IP's and the rest with static host assignments, all in the same /24 subnet.

The static assignments are assigned using option 82 circuit-id to set a tag which is then matched in the dhcp-host declaration. For the most part I have managed to get it working, but I have noticed something in my logs which I am not sure is a bug or just my general lack of understanding...

Basically, if a DHCP inform packet comes in, the circuit-id gets matched, and a corresponding ack gets sent by the server. However, if a DHCP request comes in, the server doesn't seem to be able to match the circuit ID at all and responds with "dnsmasq-dhcp[5631]: no address range available for DHCP request via eth0"

I have confirmed using tshark that the incoming DHCP request packet contains a circuit-id that matches an assigned dhcp-host entry.

My dnsmasq.conf has only the following range:

dhcp-range=172.16.127.16,172.16.127.49,255.255.255.0,12h

I have a seperate .conf containing the static entries, repeated like so:

dhcp-circuitid=set:lag_103_1309_91,lag-103:1309.91
dhcp-host=net:lag_103_1309_91,172.16.127.141,Switch1
dhcp-option=net:lag_103_1309_91,12,Switch1

dhcp-circuitid=set:lag_104_1408_93,lag-104:1408.93
dhcp-host=net:lag_104_1408_93,172.16.127.139,Switch2
dhcp-option=net:lag_104_1408_93,12,Switch1

Best Regards,

Max
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