The Linux bridge agent uses a configuration file located at /etc/neutron/plugins/ml2/linuxbridge_agent
.ini. The most common options are as follows:

[linux_bridge]
...
physical_interface_mappings = ... 
 
[vxlan]
...
enable_vxlan = ...
vxlan_group = ...
l2_population = ...
local_ip = ...
arp_responder = ... 

[securitygroup]
...
firewall_driver = ...