Sample dnsmasq.conf file that uses option-82 circuit-id to assign fixed IP address

dnsmasq.conf

#domain-needed
bogus-priv
expand-hosts

addn-hosts=/var/lib/dnsmasq/hosts

# interfaces ...
interface=eth1

# DCHP configs ...
log-dhcp
dhcp-script=/var/lib/dnsmasq/dhcp-script.sh

dhcp-option=option:dns-server,192.168.10.89
dhcp-option=150,192.168.10.89

###
### Map ex-staging switch ports to tags, which
### we will then use to hardcode IP addresses.
### the circuit-id is the <port>:<vlan-name>
###

dhcp-circuitid=set:port_0,ge-0/0/0.0:staging
dhcp-circuitid=set:port_1,ge-0/0/1.0:staging
dhcp-circuitid=set:port_2,ge-0/0/2.0:staging
dhcp-circuitid=set:port_3,ge-0/0/3.0:staging
dhcp-circuitid=set:port_4,ge-0/0/4.0:staging
dhcp-circuitid=set:port_5,ge-0/0/5.0:staging
dhcp-circuitid=set:port_6,ge-0/0/6.0:staging
dhcp-circuitid=set:port_7,ge-0/0/7.0:staging
dhcp-circuitid=set:port_8,ge-0/0/8.0:staging
dhcp-circuitid=set:port_9,ge-0/0/9.0:staging
dhcp-circuitid=set:port_10,ge-0/0/10.0:staging
dhcp-circuitid=set:port_11,ge-0/0/11.0:staging
dhcp-circuitid=set:port_12,ge-0/0/12.0:staging
dhcp-circuitid=set:port_13,ge-0/0/13.0:staging
dhcp-circuitid=set:port_14,ge-0/0/14.0:staging
dhcp-circuitid=set:port_15,ge-0/0/15.0:staging
dhcp-circuitid=set:port_16,ge-0/0/16.0:staging
dhcp-circuitid=set:port_17,ge-0/0/17.0:staging
dhcp-circuitid=set:port_18,ge-0/0/18.0:staging
dhcp-circuitid=set:port_19,ge-0/0/19.0:staging

###
### single ip-addresss range statements mapping
### tag from circuit-id to common tag names for further
### option settings
###

dhcp-range=net:port_0,ex_staging,192.168.11.10,192.168.11.10,255.255.255.0
dhcp-range=net:port_1,ex_staging,192.168.11.11,192.168.11.11,255.255.255.0
dhcp-range=net:port_2,ex_staging,192.168.11.12,192.168.11.12,255.255.255.0
dhcp-range=net:port_3,ex_staging,192.168.11.13,192.168.11.13,255.255.255.0
dhcp-range=net:port_4,srx_staging,192.168.11.14,192.168.11.14,255.255.255.0
dhcp-range=net:port_5,srx_staging,192.168.11.15,192.168.11.15,255.255.255.0

###
### common options
###

dhcp-option=option:router,192.168.11.1

###
### device specific options
###

dhcp-option=ex_staging,option:bootfile-name,ex_junos.conf
dhcp-option=srx_staging,option:bootfile-name,srx_junos.conf