--bridge-interface=<interface>,<alias>[,<alias>]
Treat DHCP (v4 and v6) requests and IPv6 Router Solicit packets arriving at any of the <alias> interfaces as if they had arrived at <interface>. This option allows dnsmasq to provide DHCP and RA service over unaddressed and unbridged Ethernet interfaces, e.g. on an OpenStack compute host where each such interface is a TAP interface to a VM, or as in "old style bridging" on BSD platforms. A trailing '*' wildcard can be used in each <alias>.

It is permissible to add more than one alias using more than one --bridge-interface option since --bridge-interface=int1,alias1,alias2 is exactly equivalent to --bridge-interface=int1,alias1 --bridge-interface=int1,alias2