l3_agent.ini

                [DEFAULT]
# Show debugging output in log (sets DEBUG log level output)
# debug = False

# L3 requires that an interface driver be set. Choose the one that best
# matches your plugin.
# interface_driver =

# Example of interface_driver option for OVS based plugins (OVS, Ryu, NEC)
# that supports L3 agent
# interface_driver = neutron.agent.linux.interface.OVSInterfaceDriver

# MTU setting for device.
# network_device_mtu =

# Use veth for an OVS interface or not.
# Support kernels with limited namespace support
# (e.g. RHEL 6.5) so long as ovs_use_veth is set to True.
# ovs_use_veth = False

# Example of interface_driver option for LinuxBridge
# interface_driver = neutron.agent.linux.interface.BridgeInterfaceDriver

# Allow overlapping IP (Must have kernel build with CONFIG_NET_NS=y and
# iproute2 package that supports namespaces). This option is deprecated and
# will be removed in a future release, at which point the old behavior of
# use_namespaces = True will be enforced.
# use_namespaces = True

# If use_namespaces is set as False then the agent can only configure one router.

# This is done by setting the specific router_id.
# router_id =

# When external_network_bridge is set, each L3 agent can be associated
# with no more than one external network. This value should be set to the UUID
# of that external network. To allow L3 agent support multiple external
# networks, both the external_network_bridge and gateway_external_network_id
# must be left empty.
# gateway_external_network_id =

# With IPv6, the network used for the external gateway does not need
# to have an associated subnet, since the automatically assigned
# link-local address (LLA) can be used. However, an IPv6 gateway address
# is needed for use as the next-hop for the default route. If no IPv6
# gateway address is configured here, (and only then) the neutron router
# will be configured to get its default route from router advertisements (RAs)
# from the upstream router; in which case the upstream router must also be
# configured to send these RAs.
# The ipv6_gateway, when configured, should be the LLA of the interface
# on the upstream router. If a next-hop using a global unique address (GUA)
# is desired, it needs to be done via a subnet allocated to the network
# and not through this parameter.
# ipv6_gateway =

# Indicates that this L3 agent should also handle routers that do not have
# an external network gateway configured.  This option should be True only
# for a single agent in a Neutron deployment, and may be False for all agents
# if all routers must have an external network gateway
# handle_internal_only_routers = True

# Name of bridge used for external network traffic. This should be set to
# empty value for the linux bridge. when this parameter is set, each L3 agent
# can be associated with no more than one external network.
# external_network_bridge = br-ex

# TCP Port used by Neutron metadata server
# metadata_port = 9697

# Send this many gratuitous ARPs for HA setup. Set it below or equal to 0
# to disable this feature.
# send_arp_for_ha = 3

# seconds between re-sync routers' data if needed
# periodic_interval = 40

# seconds to start to sync routers' data after
# starting agent
# periodic_fuzzy_delay = 5

# enable_metadata_proxy, which is true by default, can be set to False
# if the Nova metadata server is not available
# enable_metadata_proxy = True

# Iptables mangle mark used to mark metadata valid requests
# metadata_access_mark = 0x1

# Iptables mangle mark used to mark ingress from external network
# external_ingress_mark = 0x2

# router_delete_namespaces, which is false by default, can be set to True if
# namespaces can be deleted cleanly on the host running the L3 agent.
# Do not enable this until you understand the problem with the Linux iproute
# utility mentioned in https://bugs.launchpad.net/neutron/+bug/1052535 and
# you are sure that your version of iproute does not suffer from the problem.
# If True, namespaces will be deleted when a router is destroyed.
# router_delete_namespaces = False

# Timeout for ovs-vsctl commands.
# If the timeout expires, ovs commands will fail with ALARMCLOCK error.
# ovs_vsctl_timeout = 10

# The working mode for the agent. Allowed values are:
# - legacy: this preserves the existing behavior where the L3 agent is
#   deployed on a centralized networking node to provide L3 services
#   like DNAT, and SNAT. Use this mode if you do not want to adopt DVR.
# - dvr: this mode enables DVR functionality, and must be used for an L3
#   agent that runs on a compute host.
# - dvr_snat: this enables centralized SNAT support in conjunction with
#   DVR. This mode must be used for an L3 agent running on a centralized
#   node (or in single-host deployments, e.g. devstack).
# agent_mode = legacy

# Location to store keepalived and all HA configurations
# ha_confs_path = $state_path/ha_confs

# VRRP authentication type AH/PASS
# ha_vrrp_auth_type = PASS

# VRRP authentication password
# ha_vrrp_auth_password =

# The advertisement interval in seconds
# ha_vrrp_advert_int = 2