Networking configuration options

Networking configuration options

The options and descriptions listed in this introduction are auto generated from the code in the Networking service project, which provides software-defined networking between VMs run in Compute. The list contains common options, while the subsections list the options for the various networking plug-ins.

Description of common configuration options
Configuration option = Default value Description
[DEFAULT]  
agent_down_time = 75 (Integer) Seconds to regard the agent is down; should be at least twice report_interval, to be sure the agent is down for good.
allow_automatic_dhcp_failover = True (Boolean) Automatically remove networks from offline DHCP agents.
allow_automatic_l3agent_failover = False (Boolean) Automatically reschedule routers from offline L3 agents to online L3 agents.
api_workers = None (Integer) Number of separate API worker processes for service. If not specified, the default is equal to the number of CPUs available for best performance.
auth_ca_cert = None (String) Certificate Authority public key (CA cert) file for ssl
auth_strategy = keystone (String) The type of authentication to use
base_mac = fa:16:3e:00:00:00 (String) The base MAC address Neutron will use for VIFs. The first 3 octets will remain unchanged. If the 4th octet is not 00, it will also be used. The others will be randomly generated.
bind_host = 0.0.0.0 (String) The host IP to bind to
bind_port = 9696 (Port number) The port to bind to
cache_url = (String) DEPRECATED: URL to connect to the cache back end. This option is deprecated in the Newton release and will be removed. Please add a [cache] group for oslo.cache in your neutron.conf and add “enable” and “backend” options in this section.
core_plugin = None (String) The core plugin Neutron will use
default_availability_zones = (List) Default value of availability zone hints. The availability zone aware schedulers use this when the resources availability_zone_hints is empty. Multiple availability zones can be specified by a comma separated string. This value can be empty. In this case, even if availability_zone_hints for a resource is empty, availability zone is considered for high availability while scheduling the resource.
dhcp_agent_notification = True (Boolean) Allow sending resource operation notification to DHCP agent
dhcp_agents_per_network = 1 (Integer) Number of DHCP agents scheduled to host a tenant network. If this number is greater than 1, the scheduler automatically assigns multiple DHCP agents for a given tenant network, providing high availability for DHCP service.
dhcp_broadcast_reply = False (Boolean) Use broadcast in DHCP replies.
dhcp_confs = $state_path/dhcp (String) Location to store DHCP server config files.
dhcp_domain = openstacklocal (String) DEPRECATED: Domain to use for building the hostnames. This option is deprecated. It has been moved to neutron.conf as dns_domain. It will be removed in a future release.
dhcp_lease_duration = 86400 (Integer) DHCP lease duration (in seconds). Use -1 to tell dnsmasq to use infinite lease times.
dhcp_load_type = networks (String) Representing the resource type whose load is being reported by the agent. This can be “networks”, “subnets” or “ports”. When specified (Default is networks), the server will extract particular load sent as part of its agent configuration object from the agent report state, which is the number of resources being consumed, at every report_interval.dhcp_load_type can be used in combination with network_scheduler_driver = neutron.scheduler.dhcp_agent_scheduler.WeightScheduler When the network_scheduler_driver is WeightScheduler, dhcp_load_type can be configured to represent the choice for the resource being balanced. Example: dhcp_load_type=networks
dns_domain = openstacklocal (String) Domain to use for building the hostnames
enable_new_agents = True (Boolean) Agent starts with admin_state_up=False when enable_new_agents=False. In the case, user’s resources will not be scheduled automatically to the agent until admin changes admin_state_up to True.
enable_services_on_agents_with_admin_state_down = False (Boolean) Enable services on an agent with admin_state_up False. If this option is False, when admin_state_up of an agent is turned False, services on it will be disabled. Agents with admin_state_up False are not selected for automatic scheduling regardless of this option. But manual scheduling to such agents is available if this option is True.
executor_thread_pool_size = 64 (Integer) Size of executor thread pool.
external_dns_driver = None (String) Driver for external DNS integration.
global_physnet_mtu = 1500 (Integer) MTU of the underlying physical network. Neutron uses this value to calculate MTU for all virtual network components. For flat and VLAN networks, neutron uses this value without modification. For overlay networks such as VXLAN, neutron automatically subtracts the overlay protocol overhead from this value. Defaults to 1500, the standard value for Ethernet.
ip_lib_force_root = False (Boolean) Force ip_lib calls to use the root helper
ipam_driver = internal (String) Neutron IPAM (IP address management) driver to use. By default, the reference implementation of the Neutron IPAM driver is used.
mac_generation_retries = 16 (Integer) DEPRECATED: How many times Neutron will retry MAC generation. This option is now obsolete and so is deprecated to be removed in the Ocata release.
max_allowed_address_pair = 10 (Integer) Maximum number of allowed address pairs
max_dns_nameservers = 5 (Integer) Maximum number of DNS nameservers per subnet
max_fixed_ips_per_port = 5 (Integer) DEPRECATED: Maximum number of fixed ips per port. This option is deprecated and will be removed in the Ocata release.
max_rtr_adv_interval = 100 (Integer) MaxRtrAdvInterval setting for radvd.conf
max_subnet_host_routes = 20 (Integer) Maximum number of host routes per subnet
min_rtr_adv_interval = 30 (Integer) MinRtrAdvInterval setting for radvd.conf
periodic_fuzzy_delay = 5 (Integer) Range of seconds to randomly delay when starting the periodic task scheduler to reduce stampeding. (Disable by setting to 0)
periodic_interval = 40 (Integer) Seconds between running periodic tasks.
report_interval = 300 (Integer) Interval between two metering reports
state_path = /var/lib/neutron (String) Where to store Neutron state files. This directory must be writable by the agent.
vlan_transparent = False (Boolean) If True, then allow plugins that support it to create VLAN transparent networks.
web_framework = legacy (String) This will choose the web framework in which to run the Neutron API server. ‘pecan’ is a new experimental rewrite of the API server.
[AGENT]  
check_child_processes_action = respawn (String) Action to be executed when a child process dies
check_child_processes_interval = 60 (Integer) Interval between checks of child process liveness (seconds), use 0 to disable
debug_iptables_rules = False (Boolean) Duplicate every iptables difference calculation to ensure the format being generated matches the format of iptables-save. This option should not be turned on for production systems because it imposes a performance penalty.
log_agent_heartbeats = False (Boolean) Log agent heartbeats
polling_interval = 2 (Integer) The number of seconds the agent will wait between polling for local device changes.
root_helper = sudo (String) Root helper application. Use ‘sudo neutron-rootwrap /etc/neutron/rootwrap.conf’ to use the real root filter facility. Change to ‘sudo’ to skip the filtering and just run the command directly.
root_helper_daemon = None (String) Root helper daemon application to use when possible.
[profiler]  
connection_string = messaging://

(String) Connection string for a notifier backend. Default value is messaging:// which sets the notifier to oslo_messaging.

Examples of possible values:

  • messaging://: use oslo_messaging driver for sending notifications.
enabled = False

(Boolean) Enables the profiling for all services on this node. Default value is False (fully disable the profiling feature).

Possible values:

  • True: Enables the feature
  • False: Disables the feature. The profiling cannot be started via this project operations. If the profiling is triggered by another project, this project part will be empty.
hmac_keys = SECRET_KEY

(String) Secret key(s) to use for encrypting context data for performance profiling. This string value should have the following format: <key1>[,<key2>,...<keyn>], where each key is some random string. A user who triggers the profiling via the REST API has to set one of these keys in the headers of the REST API call to include profiling results of this node for this particular project.

Both “enabled” flag and “hmac_keys” config options should be set to enable profiling. Also, to generate correct profiling information across all services at least one key needs to be consistent between OpenStack projects. This ensures it can be used from client side to generate the trace, containing information from all possible resources.

trace_sqlalchemy = False

(Boolean) Enables SQL requests profiling in services. Default value is False (SQL requests won’t be traced).

Possible values:

  • True: Enables SQL requests profiling. Each SQL query will be part of the trace and can the be analyzed by how much time was spent for that.
  • False: Disables SQL requests profiling. The spent time is only shown on a higher level of operations. Single SQL queries cannot be analyzed this way.
[qos]  
notification_drivers = message_queue (List) Drivers list to use to send the update notification
[service_providers]  
service_provider = [] (Multi-valued) Defines providers for advanced services using the format: <service_type>:<name>:<driver>[:default]

Networking plug-ins

OpenStack Networking introduces the concept of a plug-in, which is a back-end implementation of the OpenStack Networking API. A plug-in can use a variety of technologies to implement the logical API requests. Some OpenStack Networking plug-ins might use basic Linux VLANs and IP tables, while others might use more advanced technologies, such as L2-in-L3 tunneling or OpenFlow. These sections detail the configuration options for the various plug-ins.

Modular Layer 2 (ml2) plug-in configuration options

The Modular Layer 2 (ml2) plug-in has two components: network types and mechanisms. You can configure these components separately. The ml2 plugin also allows administrators to perform a partial specification, where some options are specified explicitly in the configuration, and the remainder is allowed to be chosen automatically by the Compute service.

This section describes the available configuration options.

Note

OpenFlow Agent (ofagent) Mechanism driver has been removed as of Newton.

Description of ML2 configuration options
Configuration option = Default value Description
[ml2]  
extension_drivers = (List) An ordered list of extension driver entrypoints to be loaded from the neutron.ml2.extension_drivers namespace. For example: extension_drivers = port_security,qos
external_network_type = None (String) Default network type for external networks when no provider attributes are specified. By default it is None, which means that if provider attributes are not specified while creating external networks then they will have the same type as tenant networks. Allowed values for external_network_type config option depend on the network type values configured in type_drivers config option.
mechanism_drivers = (List) An ordered list of networking mechanism driver entrypoints to be loaded from the neutron.ml2.mechanism_drivers namespace.
overlay_ip_version = 4 (Integer) IP version of all overlay (tunnel) network endpoints. Use a value of 4 for IPv4 or 6 for IPv6.
path_mtu = 0 (Integer) Maximum size of an IP packet (MTU) that can traverse the underlying physical network infrastructure without fragmentation when using an overlay/tunnel protocol. This option allows specifying a physical network MTU value that differs from the default global_physnet_mtu value.
physical_network_mtus = (List) A list of mappings of physical networks to MTU values. The format of the mapping is <physnet>:<mtu val>. This mapping allows specifying a physical network MTU value that differs from the default global_physnet_mtu value.
tenant_network_types = local (List) Ordered list of network_types to allocate as tenant networks. The default value ‘local’ is useful for single-box testing but provides no connectivity between hosts.
type_drivers = local, flat, vlan, gre, vxlan, geneve (List) List of network type driver entrypoints to be loaded from the neutron.ml2.type_drivers namespace.

Modular Layer 2 (ml2) Flat Type configuration options

Description of ML2 Flat mechanism driver configuration options
Configuration option = Default value Description
[ml2_type_flat]  
flat_networks = * (List) List of physical_network names with which flat networks can be created. Use default ‘*’ to allow flat networks with arbitrary physical_network names. Use an empty list to disable flat networks.

Modular Layer 2 (ml2) Geneve Type configuration options

Description of ML2 Geneve type driver configuration options
Configuration option = Default value Description
[ml2_type_geneve]  
max_header_size = 30 (Integer) Geneve encapsulation header size is dynamic, this value is used to calculate the maximum MTU for the driver. This is the sum of the sizes of the outer ETH + IP + UDP + GENEVE header sizes. The default size for this field is 50, which is the size of the Geneve header without any additional option headers.
vni_ranges = (List) Comma-separated list of <vni_min>:<vni_max> tuples enumerating ranges of Geneve VNI IDs that are available for tenant network allocation

Modular Layer 2 (ml2) GRE Type configuration options

Description of ML2 GRE configuration options
Configuration option = Default value Description
[ml2_type_gre]  
tunnel_id_ranges = (List) Comma-separated list of <tun_min>:<tun_max> tuples enumerating ranges of GRE tunnel IDs that are available for tenant network allocation

Modular Layer 2 (ml2) VLAN Type configuration options

Description of ML2 VLAN configuration options
Configuration option = Default value Description
[ml2_type_vlan]  
network_vlan_ranges = (List) List of <physical_network>:<vlan_min>:<vlan_max> or <physical_network> specifying physical_network names usable for VLAN provider and tenant networks, as well as ranges of VLAN tags on each available for allocation to tenant networks.

Modular Layer 2 (ml2) VXLAN Type configuration options

Description of ML2 VXLN configuration options
Configuration option = Default value Description
[ml2_type_vxlan]  
vni_ranges = (List) Comma-separated list of <vni_min>:<vni_max> tuples enumerating ranges of VXLAN VNI IDs that are available for tenant network allocation
vxlan_group = None (String) Multicast group for VXLAN. When configured, will enable sending all broadcast traffic to this multicast group. When left unconfigured, will disable multicast VXLAN mode.

Modular Layer 2 (ml2) L2 Population Mechanism configuration options

Description of ML2 L2 population configuration options
Configuration option = Default value Description
[l2pop]  
agent_boot_time = 180 (Integer) Delay within which agent is expected to update existing ports whent it restarts

Modular Layer 2 (ml2) SR-IOV Mechanism configuration options

Description of ML2 ML2 SR-IOV driver configuration options
Configuration option = Default value Description
[ml2_sriov]  
supported_pci_vendor_devs = None (List) DEPRECATED: Comma-separated list of supported PCI vendor devices, as defined by vendor_id:product_id according to the PCI ID Repository. Default None accept all PCI vendor devicesDEPRECATED: This option is deprecated in the Newton release and will be removed in the Ocata release. Starting from Ocata the mechanism driver will accept all PCI vendor devices.

Agent

Use the following options to alter agent-related settings.

Description of agent configuration options
Configuration option = Default value Description
[DEFAULT]  
external_pids = $state_path/external/pids (String) Location to store child pid files
[AGENT]  
agent_type = Open vSwitch agent (String) DEPRECATED: Selects the Agent Type reported
availability_zone = nova (String) Availability zone of this node

Layer 2 agent configuration options

Description of L2 agent extension configuration options
Configuration option = Default value Description
[agent]  
extensions = (List) Extensions list to use

Linux Bridge agent configuration options

Description of Linux Bridge agent configuration options
Configuration option = Default value Description
[AGENT]  
prevent_arp_spoofing = True (Boolean) DEPRECATED: Enable suppression of ARP responses that don’t match an IP address that belongs to the port from which they originate. Note: This prevents the VMs attached to this agent from spoofing, it doesn’t protect them from other devices which have the capability to spoof (e.g. bare metal or VMs attached to agents without this flag set to True). Spoofing rules will not be added to any ports that have port security disabled. For LinuxBridge, this requires ebtables. For OVS, it requires a version that supports matching ARP headers. This option will be removed in Ocata so the only way to disable protection will be via the port security extension.
quitting_rpc_timeout = 10 (Integer) Set new timeout in seconds for new rpc calls after agent receives SIGTERM. If value is set to 0, rpc timeout won’t be changed
[LINUX_BRIDGE]  
bridge_mappings = (List) List of <physical_network>:<physical_bridge>
physical_interface_mappings = (List) Comma-separated list of <physical_network>:<physical_interface> tuples mapping physical network names to the agent’s node-specific physical network interfaces to be used for flat and VLAN networks. All physical networks listed in network_vlan_ranges on the server should have mappings to appropriate interfaces on each agent.
[VXLAN]  
arp_responder = False (Boolean) Enable local ARP responder which provides local responses instead of performing ARP broadcast into the overlay. Enabling local ARP responder is not fully compatible with the allowed-address-pairs extension.
enable_vxlan = True (Boolean) Enable VXLAN on the agent. Can be enabled when agent is managed by ml2 plugin using linuxbridge mechanism driver
l2_population = False (Boolean) Extension to use alongside ml2 plugin’s l2population mechanism driver. It enables the plugin to populate VXLAN forwarding table.
local_ip = None (IP) IP address of local overlay (tunnel) network endpoint. Use either an IPv4 or IPv6 address that resides on one of the host network interfaces. The IP version of this value must match the value of the ‘overlay_ip_version’ option in the ML2 plug-in configuration file on the neutron server node(s).
tos = None (Integer) TOS for vxlan interface protocol packets.
ttl = None (Integer) TTL for vxlan interface protocol packets.
vxlan_group = 224.0.0.1 (String) Multicast group(s) for vxlan interface. A range of group addresses may be specified by using CIDR notation. Specifying a range allows different VNIs to use different group addresses, reducing or eliminating spurious broadcast traffic to the tunnel endpoints. To reserve a unique group for each possible (24-bit) VNI, use a /8 such as 239.0.0.0/8. This setting must be the same on all the agents.

Open vSwitch agent configuration options

Description of Open vSwitch agent configuration options
Configuration option = Default value Description
[DEFAULT]  
ovs_integration_bridge = br-int (String) Name of Open vSwitch bridge to use
ovs_use_veth = False (Boolean) Uses 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_vsctl_timeout = 10 (Integer) Timeout in seconds for ovs-vsctl commands. If the timeout expires, ovs commands will fail with ALARMCLOCK error.
[AGENT]  
arp_responder = False (Boolean) Enable local ARP responder if it is supported. Requires OVS 2.1 and ML2 l2population driver. Allows the switch (when supporting an overlay) to respond to an ARP request locally without performing a costly ARP broadcast into the overlay.
dont_fragment = True (Boolean) Set or un-set the don’t fragment (DF) bit on outgoing IP packet carrying GRE/VXLAN tunnel.
drop_flows_on_start = False (Boolean) Reset flow table on start. Setting this to True will cause brief traffic interruption.
enable_distributed_routing = False (Boolean) Make the l2 agent run in DVR mode.
l2_population = False (Boolean) Use ML2 l2population mechanism driver to learn remote MAC and IPs and improve tunnel scalability.
minimize_polling = True (Boolean) Minimize polling by monitoring ovsdb for interface changes.
ovsdb_monitor_respawn_interval = 30 (Integer) The number of seconds to wait before respawning the ovsdb monitor after losing communication with it.
prevent_arp_spoofing = True (Boolean) DEPRECATED: Enable suppression of ARP responses that don’t match an IP address that belongs to the port from which they originate. Note: This prevents the VMs attached to this agent from spoofing, it doesn’t protect them from other devices which have the capability to spoof (e.g. bare metal or VMs attached to agents without this flag set to True). Spoofing rules will not be added to any ports that have port security disabled. For LinuxBridge, this requires ebtables. For OVS, it requires a version that supports matching ARP headers. This option will be removed in Ocata so the only way to disable protection will be via the port security extension.
quitting_rpc_timeout = 10 (Integer) Set new timeout in seconds for new rpc calls after agent receives SIGTERM. If value is set to 0, rpc timeout won’t be changed
tunnel_csum = False (Boolean) Set or un-set the tunnel header checksum on outgoing IP packet carrying GRE/VXLAN tunnel.
tunnel_types = (List) Network types supported by the agent (gre and/or vxlan).
veth_mtu = 9000 (Integer) MTU size of veth interfaces
vxlan_udp_port = 4789 (Port number) The UDP port to use for VXLAN tunnels.
[OVS]  
bridge_mappings = (List) Comma-separated list of <physical_network>:<bridge> tuples mapping physical network names to the agent’s node-specific Open vSwitch bridge names to be used for flat and VLAN networks. The length of bridge names should be no more than 11. Each bridge must exist, and should have a physical network interface configured as a port. All physical networks configured on the server should have mappings to appropriate bridges on each agent. Note: If you remove a bridge from this mapping, make sure to disconnect it from the integration bridge as it won’t be managed by the agent anymore.
datapath_type = system (String) OVS datapath to use. ‘system’ is the default value and corresponds to the kernel datapath. To enable the userspace datapath set this value to ‘netdev’.
int_peer_patch_port = patch-tun (String) Peer patch port in integration bridge for tunnel bridge.
integration_bridge = br-int (String) Integration bridge to use. Do not change this parameter unless you have a good reason to. This is the name of the OVS integration bridge. There is one per hypervisor. The integration bridge acts as a virtual ‘patch bay’. All VM VIFs are attached to this bridge and then ‘patched’ according to their network connectivity.
local_ip = None (IP) IP address of local overlay (tunnel) network endpoint. Use either an IPv4 or IPv6 address that resides on one of the host network interfaces. The IP version of this value must match the value of the ‘overlay_ip_version’ option in the ML2 plug-in configuration file on the neutron server node(s).
of_connect_timeout = 30 (Integer) Timeout in seconds to wait for the local switch connecting the controller. Used only for ‘native’ driver.
of_interface = native (String) OpenFlow interface to use.
of_listen_address = 127.0.0.1 (IP) Address to listen on for OpenFlow connections. Used only for ‘native’ driver.
of_listen_port = 6633 (Port number) Port to listen on for OpenFlow connections. Used only for ‘native’ driver.
of_request_timeout = 10 (Integer) Timeout in seconds to wait for a single OpenFlow request. Used only for ‘native’ driver.
ovsdb_connection = tcp:127.0.0.1:6640 (String) The connection string for the native OVSDB backend. Requires the native ovsdb_interface to be enabled.
ovsdb_interface = native (String) The interface for interacting with the OVSDB
tun_peer_patch_port = patch-int (String) Peer patch port in tunnel bridge for integration bridge.
tunnel_bridge = br-tun (String) Tunnel bridge to use.
use_veth_interconnection = False (Boolean) Use veths instead of patch ports to interconnect the integration bridge to physical networks. Support kernel without Open vSwitch patch port support so long as it is set to True.
vhostuser_socket_dir = /var/run/openvswitch (String) OVS vhost-user socket directory.

SR-IOV agent configuration options

Description of SR-IOV agent configuration options
Configuration option = Default value Description
[SRIOV_NIC]  
exclude_devices = (List) Comma-separated list of <network_device>:<vfs_to_exclude> tuples, mapping network_device to the agent’s node-specific list of virtual functions that should not be used for virtual networking. vfs_to_exclude is a semicolon-separated list of virtual functions to exclude from network_device. The network_device in the mapping should appear in the physical_device_mappings list.
physical_device_mappings = (List) Comma-separated list of <physical_network>:<network_device> tuples mapping physical network names to the agent’s node-specific physical network device interfaces of SR-IOV physical function to be used for VLAN networks. All physical networks listed in network_vlan_ranges on the server should have mappings to appropriate interfaces on each agent.

MacVTap Agent configuration options

Description of MacVTap agent configuration options
Configuration option = Default value Description
[AGENT]  
quitting_rpc_timeout = 10 (Integer) Set new timeout in seconds for new rpc calls after agent receives SIGTERM. If value is set to 0, rpc timeout won’t be changed
[macvtap]  
physical_interface_mappings = (List) Comma-separated list of <physical_network>:<physical_interface> tuples mapping physical network names to the agent’s node-specific physical network interfaces to be used for flat and VLAN networks. All physical networks listed in network_vlan_ranges on the server should have mappings to appropriate interfaces on each agent.

IPv6 Prefix Delegation configuration options

Description of IPv6 Prefix Delegation driver configuration options
Configuration option = Default value Description
[DEFAULT]  
pd_confs = $state_path/pd (String) Location to store IPv6 PD files.
pd_dhcp_driver = dibbler (String) Service to handle DHCPv6 Prefix delegation.
vendor_pen = 8888 (String) A decimal value as Vendor’s Registered Private Enterprise Number as required by RFC3315 DUID-EN.

API

Use the following options to alter API-related settings.

Description of API configuration options
Configuration option = Default value Description
[DEFAULT]  
allow_bulk = True (Boolean) Allow the usage of the bulk API
allow_pagination = True (Boolean) DEPRECATED: Allow the usage of the pagination. This option has been deprecated and will now be enabled unconditionally.
allow_sorting = True (Boolean) DEPRECATED: Allow the usage of the sorting. This option has been deprecated and will now be enabled unconditionally.
api_extensions_path = (String) The path for API extensions. Note that this can be a colon-separated list of paths. For example: api_extensions_path = extensions:/path/to/more/exts:/even/more/exts. The __path__ of neutron.extensions is appended to this, so if your extensions are in there you don’t need to specify them here.
api_paste_config = api-paste.ini (String) File name for the paste.deploy config for api service
backlog = 4096 (Integer) Number of backlog requests to configure the socket with
client_socket_timeout = 900 (Integer) Timeout for client connections’ socket operations. If an incoming connection is idle for this number of seconds it will be closed. A value of ‘0’ means wait forever.
max_header_line = 16384 (Integer) Maximum line size of message headers to be accepted. max_header_line may need to be increased when using large tokens (typically those generated when keystone is configured to use PKI tokens with big service catalogs).
pagination_max_limit = -1 (String) The maximum number of items returned in a single response, value was ‘infinite’ or negative integer means no limit
retry_until_window = 30 (Integer) Number of seconds to keep retrying to listen
service_plugins = (List) The service plugins Neutron will use
tcp_keepidle = 600 (Integer) Sets the value of TCP_KEEPIDLE in seconds for each server socket. Not supported on OS X.
use_ssl = False (Boolean) Enable SSL on the API server
wsgi_default_pool_size = 100 (Integer) Size of the pool of greenthreads used by wsgi
wsgi_keep_alive = True (Boolean) If False, closes the client socket connection explicitly.
wsgi_log_format = %(client_ip)s "%(request_line)s" status: %(status_code)s  len: %(body_length)s time: %(wall_seconds).7f (String) A python format string that is used as the template to generate log lines. The following values can beformatted into it: client_ip, date_time, request_line, status_code, body_length, wall_seconds.
[oslo_middleware]  
enable_proxy_headers_parsing = False (Boolean) Whether the application is behind a proxy or not. This determines if the middleware should parse the headers or not.
max_request_body_size = 114688 (Integer) The maximum body size for each request, in bytes.
secure_proxy_ssl_header = X-Forwarded-Proto (String) DEPRECATED: The HTTP Header that will be used to determine what the original request protocol scheme was, even if it was hidden by a SSL termination proxy.
[oslo_versionedobjects]  
fatal_exception_format_errors = False (Boolean) Make exception message format errors fatal

Compute

Use the following options to alter Compute-related settings.

Description of Compute configuration options
Configuration option = Default value Description
[DEFAULT]  
notify_nova_on_port_data_changes = True (Boolean) Send notification to nova when port data (fixed_ips/floatingip) changes so nova can update its cache.
notify_nova_on_port_status_changes = True (Boolean) Send notification to nova when port status changes
nova_client_cert = (String) Client certificate for nova metadata api server.
nova_client_priv_key = (String) Private key of client certificate.
send_events_interval = 2 (Integer) Number of seconds between sending events to nova if there are any events to send.

DHCP agent

Use the following options to alter Database-related settings.

Description of DHCP agent configuration options
Configuration option = Default value Description
[DEFAULT]  
advertise_mtu = True (Boolean) DEPRECATED: If True, advertise network MTU values if core plugin calculates them. MTU is advertised to running instances via DHCP and RA MTU options.
dhcp_driver = neutron.agent.linux.dhcp.Dnsmasq (String) The driver used to manage the DHCP server.
dnsmasq_base_log_dir = None (String) Base log dir for dnsmasq logging. The log contains DHCP and DNS log information and is useful for debugging issues with either DHCP or DNS. If this section is null, disable dnsmasq log.
dnsmasq_config_file = (String) Override the default dnsmasq settings with this file.
dnsmasq_dns_servers = (List) Comma-separated list of the DNS servers which will be used as forwarders.
dnsmasq_lease_max = 16777216 (Integer) Limit number of leases to prevent a denial-of-service.
dnsmasq_local_resolv = False (Boolean) Enables the dnsmasq service to provide name resolution for instances via DNS resolvers on the host running the DHCP agent. Effectively removes the ‘–no-resolv’ option from the dnsmasq process arguments. Adding custom DNS resolvers to the ‘dnsmasq_dns_servers’ option disables this feature.
enable_isolated_metadata = False (Boolean) The DHCP server can assist with providing metadata support on isolated networks. Setting this value to True will cause the DHCP server to append specific host routes to the DHCP request. The metadata service will only be activated when the subnet does not contain any router port. The guest instance must be configured to request host routes via DHCP (Option 121). This option doesn’t have any effect when force_metadata is set to True.
enable_metadata_network = False (Boolean) Allows for serving metadata requests coming from a dedicated metadata access network whose CIDR is 169.254.169.254/16 (or larger prefix), and is connected to a Neutron router from which the VMs send metadata:1 request. In this case DHCP Option 121 will not be injected in VMs, as they will be able to reach 169.254.169.254 through a router. This option requires enable_isolated_metadata = True.
force_metadata = False (Boolean) In some cases the Neutron router is not present to provide the metadata IP but the DHCP server can be used to provide this info. Setting this value will force the DHCP server to append specific host routes to the DHCP request. If this option is set, then the metadata service will be activated for all the networks.
host = example.domain (String) Hostname to be used by the Neutron server, agents and services running on this machine. All the agents and services running on this machine must use the same host value.
interface_driver = None (String) The driver used to manage the virtual interface.
num_sync_threads = 4 (Integer) Number of threads to use during sync process. Should not exceed connection pool size configured on server.
resync_interval = 5 (Integer) The DHCP agent will resync its state with Neutron to recover from any transient notification or RPC errors. The interval is number of seconds between attempts.

Distributed virtual router

Use the following options to alter DVR-related settings.

Description of DVR configuration options
Configuration option = Default value Description
[DEFAULT]  
dvr_base_mac = fa:16:3f:00:00:00 (String) The base mac address used for unique DVR instances by Neutron. The first 3 octets will remain unchanged. If the 4th octet is not 00, it will also be used. The others will be randomly generated. The ‘dvr_base_mac’ must be different from ‘base_mac’ to avoid mixing them up with MAC’s allocated for tenant ports. A 4 octet example would be dvr_base_mac = fa:16:3f:4f:00:00. The default is 3 octet
router_distributed = False (Boolean) System-wide flag to determine the type of router that tenants can create. Only admin can override.

IPv6 router advertisement

Use the following options to alter IPv6 RA settings.

Description of IPv6 router advertisement configuration options
Configuration option = Default value Description
[DEFAULT]  
ra_confs = $state_path/ra (String) Location to store IPv6 RA config files

L3 agent

Use the following options in the l3_agent.ini file for the L3 agent.

Description of L3 agent configuration options
Configuration option = Default value Description
[DEFAULT]  
enable_snat_by_default = True (Boolean) Define the default value of enable_snat if not provided in external_gateway_info.
external_network_bridge = (String) DEPRECATED: Name of bridge used for external network traffic. When this parameter is set, the L3 agent will plug an interface directly into an external bridge which will not allow any wiring by the L2 agent. Using this will result in incorrect port statuses. This option is deprecated and will be removed in Ocata.
ha_confs_path = $state_path/ha_confs (String) Location to store keepalived/conntrackd config files
ha_vrrp_advert_int = 2 (Integer) The advertisement interval in seconds
ha_vrrp_auth_password = None (String) VRRP authentication password
ha_vrrp_auth_type = PASS (String) VRRP authentication type
host = example.domain (String) Hostname to be used by the Neutron server, agents and services running on this machine. All the agents and services running on this machine must use the same host value.
interface_driver = None (String) The driver used to manage the virtual interface.
ipv6_pd_enabled = False (Boolean) Enables IPv6 Prefix Delegation for automatic subnet CIDR allocation. Set to True to enable IPv6 Prefix Delegation for subnet allocation in a PD-capable environment. Users making subnet creation requests for IPv6 subnets without providing a CIDR or subnetpool ID will be given a CIDR via the Prefix Delegation mechanism. Note that enabling PD will override the behavior of the default IPv6 subnetpool.
l3_ha = False (Boolean) Enable HA mode for virtual routers.
l3_ha_net_cidr = 169.254.192.0/18 (String) Subnet used for the l3 HA admin network.
l3_ha_network_physical_name = (String) The physical network name with which the HA network can be created.
l3_ha_network_type = (String) The network type to use when creating the HA network for an HA router. By default or if empty, the first ‘tenant_network_types’ is used. This is helpful when the VRRP traffic should use a specific network which is not the default one.
max_l3_agents_per_router = 3 (Integer) Maximum number of L3 agents which a HA router will be scheduled on. If it is set to 0 then the router will be scheduled on every agent.
min_l3_agents_per_router = 2 (Integer) DEPRECATED: Minimum number of L3 agents that have to be available in order to allow a new HA router to be scheduled. This option is deprecated in the Newton release and will be removed for the Ocata release where the scheduling of new HA routers will always be allowed.
[AGENT]  
comment_iptables_rules = True (Boolean) Add comments to iptables rules. Set to false to disallow the addition of comments to generated iptables rules that describe each rule’s purpose. System must support the iptables comments module for addition of comments.
use_helper_for_ns_read = True (Boolean) Use the root helper when listing the namespaces on a system. This may not be required depending on the security configuration. If the root helper is not required, set this to False for a performance improvement.

Metadata Agent

Use the following options in the metadata_agent.ini file for the Metadata agent.

Description of metadata configuration options
Configuration option = Default value Description
[DEFAULT]  
metadata_backlog = 4096 (Integer) Number of backlog requests to configure the metadata server socket with
metadata_proxy_group = (String) Group (gid or name) running metadata proxy after its initialization (if empty: agent effective group).
metadata_proxy_shared_secret = (String) When proxying metadata requests, Neutron signs the Instance-ID header with a shared secret to prevent spoofing. You may select any string for a secret, but it must match here and in the configuration used by the Nova Metadata Server. NOTE: Nova uses the same config key, but in [neutron] section.
metadata_proxy_socket = $state_path/metadata_proxy (String) Location of Metadata Proxy UNIX domain socket
metadata_proxy_socket_mode = deduce (String) Metadata Proxy UNIX domain socket mode, 4 values allowed: ‘deduce’: deduce mode from metadata_proxy_user/group values, ‘user’: set metadata proxy socket mode to 0o644, to use when metadata_proxy_user is agent effective user or root, ‘group’: set metadata proxy socket mode to 0o664, to use when metadata_proxy_group is agent effective group or root, ‘all’: set metadata proxy socket mode to 0o666, to use otherwise.
metadata_proxy_user = (String) User (uid or name) running metadata proxy after its initialization (if empty: agent effective user).
metadata_proxy_watch_log = None (Boolean) Enable/Disable log watch by metadata proxy. It should be disabled when metadata_proxy_user/group is not allowed to read/write its log file and copytruncate logrotate option must be used if logrotate is enabled on metadata proxy log files. Option default value is deduced from metadata_proxy_user: watch log is enabled if metadata_proxy_user is agent effective user id/name.
metadata_workers = 0 (Integer) Number of separate worker processes for metadata server (defaults to half of the number of CPUs)
nova_metadata_insecure = False (Boolean) Allow to perform insecure SSL (https) requests to nova metadata
nova_metadata_ip = 127.0.0.1 (String) IP address used by Nova metadata server.
nova_metadata_port = 8775 (Port number) TCP Port used by Nova metadata server.
nova_metadata_protocol = http (String) Protocol to access nova metadata, http or https

Note

Previously, the neutron metadata agent connected to a neutron server via REST API using a neutron client. This is ineffective because keystone is then fully involved into the authentication process and gets overloaded.

The neutron metadata agent has been reworked to use RPC by default to connect to a server since Kilo release. This is a typical way of interacting between neutron server and its agents. If neutron server does not support metadata RPC then neutron client will be used.

Warning

Do not run the neutron-ns-metadata-proxy proxy namespace as root on a node with the L3 agent running. In OpenStack Kilo and newer, you can change the permissions of neutron-ns-metadata-proxy after the proxy installation using the metadata_proxy_user and metadata_proxy_group options.

Metering Agent

Use the following options in the metering_agent.ini file for the Metering agent.

Description of metering agent configuration options
Configuration option = Default value Description
[DEFAULT]  
driver = neutron.services.metering.drivers.noop.noop_driver.NoopMeteringDriver (String) Metering driver
measure_interval = 30 (Integer) Interval between two metering measures
[AGENT]  
report_interval = 30 (Floating point) Seconds between nodes reporting state to server; should be less than agent_down_time, best if it is half or less than agent_down_time.

Nova

Use the following options in the neutron.conf file to change nova-related settings.

Description of nova configuration options
Configuration option = Default value Description
[nova]  
auth_section = None (Unknown) Config Section from which to load plugin specific options
auth_type = None (Unknown) Authentication type to load
cafile = None (String) PEM encoded Certificate Authority to use when verifying HTTPs connections.
certfile = None (String) PEM encoded client certificate cert file
endpoint_type = public (String) Type of the nova endpoint to use. This endpoint will be looked up in the keystone catalog and should be one of public, internal or admin.
insecure = False (Boolean) Verify HTTPS connections.
keyfile = None (String) PEM encoded client certificate key file
region_name = None (String) Name of nova region to use. Useful if keystone manages more than one region.
timeout = None (Integer) Timeout value for http requests

Policy

Use the following options in the neutron.conf file to change policy settings.

Description of policy configuration options
Configuration option = Default value Description
[DEFAULT]  
allow_overlapping_ips = False (Boolean) Allow overlapping IP support in Neutron. Attention: the following parameter MUST be set to False if Neutron is being used in conjunction with Nova security groups.

Quotas

Use the following options in the neutron.conf file for the quota system.

Description of quotas configuration options
Configuration option = Default value Description
[DEFAULT]  
max_routes = 30 (Integer) Maximum number of routes per router
[QUOTAS]  
default_quota = -1 (Integer) Default number of resource allowed per tenant. A negative value means unlimited.
quota_driver = neutron.db.quota.driver.DbQuotaDriver (String) Default driver to use for quota checks.
quota_firewall = 10 (Integer) Number of firewalls allowed per tenant. A negative value means unlimited.
quota_firewall_policy = 10 (Integer) Number of firewall policies allowed per tenant. A negative value means unlimited.
quota_firewall_rule = 100 (Integer) Number of firewall rules allowed per tenant. A negative value means unlimited.
quota_floatingip = 50 (Integer) Number of floating IPs allowed per tenant. A negative value means unlimited.
quota_healthmonitor = -1 (Integer) Number of health monitors allowed per tenant. A negative value means unlimited.
quota_listener = -1 (Integer) Number of Loadbalancer Listeners allowed per tenant. A negative value means unlimited.
quota_loadbalancer = 10 (Integer) Number of LoadBalancers allowed per tenant. A negative value means unlimited.
quota_member = -1 (Integer) Number of pool members allowed per tenant. A negative value means unlimited.
quota_network = 10 (Integer) Number of networks allowed per tenant. A negative value means unlimited.
quota_pool = 10 (Integer) Number of pools allowed per tenant. A negative value means unlimited.
quota_port = 50 (Integer) Number of ports allowed per tenant. A negative value means unlimited.
quota_rbac_policy = 10 (Integer) Default number of RBAC entries allowed per tenant. A negative value means unlimited.
quota_router = 10 (Integer) Number of routers allowed per tenant. A negative value means unlimited.
quota_security_group = 10 (Integer) Number of security groups allowed per tenant. A negative value means unlimited.
quota_security_group_rule = 100 (Integer) Number of security rules allowed per tenant. A negative value means unlimited.
quota_subnet = 10 (Integer) Number of subnets allowed per tenant, A negative value means unlimited.
track_quota_usage = True (Boolean) Keep in track in the database of current resource quota usage. Plugins which do not leverage the neutron database should set this flag to False.

Scheduler

Use the following options in the neutron.conf file to change scheduler settings.

Description of scheduler configuration options
Configuration option = Default value Description
[DEFAULT]  
network_auto_schedule = True (Boolean) Allow auto scheduling networks to DHCP agent.
network_scheduler_driver = neutron.scheduler.dhcp_agent_scheduler.WeightScheduler (String) Driver to use for scheduling network to DHCP agent
router_auto_schedule = True (Boolean) Allow auto scheduling of routers to L3 agent.
router_scheduler_driver = neutron.scheduler.l3_agent_scheduler.LeastRoutersScheduler (String) Driver to use for scheduling router to a default L3 agent

Security Groups

Use the following options in the configuration file for your driver to change security group settings.

Description of security groups configuration options
Configuration option = Default value Description
[SECURITYGROUP]  
enable_ipset = True (Boolean) Use ipset to speed-up the iptables based security groups. Enabling ipset support requires that ipset is installed on L2 agent node.
enable_security_group = True (Boolean) Controls whether the neutron security group API is enabled in the server. It should be false when using no security groups or using the nova security group API.
firewall_driver = None (String) Driver for security groups firewall in the L2 agent

Note

Now Networking uses iptables to achieve security group functions. In L2 agent with enable_ipset option enabled, it makes use of IPset to improve security group’s performance, as it represents a hash set which is insensitive to the number of elements.

When a port is created, L2 agent will add an additional IPset chain to it’s iptables chain, if the security group that this port belongs to has rules between other security group, the member of that security group will be added to the ipset chain.

If a member of a security group is changed, it used to reload iptables rules which is expensive. However, when IPset option is enabled on L2 agent, it does not need to reload iptables if only members of security group were changed, it should just update an IPset.

Note

A single default security group has been introduced in order to avoid race conditions when creating a tenant’s default security group. The race conditions are caused by the uniqueness check of a new security group name. A table default_security_group implements such a group. It has tenant_id field as a primary key and security_group_id, which is an identifier of a default security group. The migration that introduces this table has a sanity check that verifies if a default security group is not duplicated in any tenant.

Misc

Description of FDB agent configuration options
Configuration option = Default value Description
[FDB]  
shared_physical_device_mappings = (List) Comma-separated list of <physical_network>:<network_device> tuples mapping physical network names to the agent’s node-specific shared physical network device between SR-IOV and OVS or SR-IOV and linux bridge
Description of QoS configuration options
Configuration option = Default value Description
[QOS]  
kernel_hz = 250 (Integer) Value of host kernel tick rate (hz) for calculating minimum burst value in bandwidth limit rules for a port with QoS. See kernel configuration file for HZ value and tc-tbf manual for more information.
tbf_latency = 50 (Integer) Value of latency (ms) for calculating size of queue for a port with QoS. See tc-tbf manual for more information.
Creative Commons Attribution 3.0 License

Except where otherwise noted, this document is licensed under Creative Commons Attribution 3.0 License. See all OpenStack Legal Documents.