Configuration Options

oslo.messaging uses oslo.config to define and manage configuration options to allow the deployer to control how an application uses the underlying messaging system.

DEFAULT

rpc_conn_pool_size

Type:

integer

Default:

30

Minimum Value:

1

Size of RPC connection pool.

Deprecated Variations

Group	Name
DEFAULT	rpc_conn_pool_size

conn_pool_min_size

Type:

integer

Default:

2

The pool size limit for connections expiration policy

conn_pool_ttl

Type:

integer

Default:

1200

The time-to-live in sec of idle connections in the pool

executor_thread_pool_size

Type:

integer

Default:

64

Size of executor thread pool when executor is threading or eventlet.

Deprecated Variations

Group	Name
DEFAULT	rpc_thread_pool_size

rpc_response_timeout

Type:

integer

Default:

60

Seconds to wait for a response from a call.

transport_url

Type:

string

Default:

rabbit://

The network address and optional user credentials for connecting to the messaging backend, in URL format. The expected format is:

driver://[user:pass@]host:port[,[userN:passN@]hostN:portN]/virtual_host?query

Example: rabbit://rabbitmq:password@127.0.0.1:5672//

For full details on the fields in the URL see the documentation of oslo_messaging.TransportURL at https://docs.openstack.org/oslo.messaging/latest/reference/transport.html

control_exchange

Type:

string

Default:

openstack

The default exchange under which topics are scoped. May be overridden by an exchange name specified in the transport_url option.

rpc_ping_enabled

Type:

boolean

Default:

False

Add an endpoint to answer to ping calls. Endpoint is named oslo_rpc_server_ping

oslo_messaging_amqp

container_name

Type:

string

Default:

<None>

Name for the AMQP container. must be globally unique. Defaults to a generated UUID

Deprecated Variations

Group	Name
amqp1	container_name

idle_timeout

Type:

integer

Default:

0

Timeout for inactive connections (in seconds)

Deprecated Variations

Group	Name
amqp1	idle_timeout

trace

Type:

boolean

Default:

False

Debug: dump AMQP frames to stdout

Deprecated Variations

Group	Name
amqp1	trace

ssl

Type:

boolean

Default:

False

Attempt to connect via SSL. If no other ssl-related parameters are given, it will use the system’s CA-bundle to verify the server’s certificate.

ssl_ca_file

Type:

string

Default:

''

CA certificate PEM file used to verify the server’s certificate

Deprecated Variations

Group	Name
amqp1	ssl_ca_file

ssl_cert_file

Type:

string

Default:

''

Self-identifying certificate PEM file for client authentication

Deprecated Variations

Group	Name
amqp1	ssl_cert_file

ssl_key_file

Type:

string

Default:

''

Private key PEM file used to sign ssl_cert_file certificate (optional)

Deprecated Variations

Group	Name
amqp1	ssl_key_file

ssl_key_password

Type:

string

Default:

<None>

Password for decrypting ssl_key_file (if encrypted)

Deprecated Variations

Group	Name
amqp1	ssl_key_password

ssl_verify_vhost

Type:

boolean

Default:

False

By default SSL checks that the name in the server’s certificate matches the hostname in the transport_url. In some configurations it may be preferable to use the virtual hostname instead, for example if the server uses the Server Name Indication TLS extension (rfc6066) to provide a certificate per virtual host. Set ssl_verify_vhost to True if the server’s SSL certificate uses the virtual host name instead of the DNS name.

sasl_mechanisms

Type:

string

Default:

''

Space separated list of acceptable SASL mechanisms

Deprecated Variations

Group	Name
amqp1	sasl_mechanisms

sasl_config_dir

Type:

string

Default:

''

Path to directory that contains the SASL configuration

Deprecated Variations

Group	Name
amqp1	sasl_config_dir

sasl_config_name

Type:

string

Default:

''

Name of configuration file (without .conf suffix)

Deprecated Variations

Group	Name
amqp1	sasl_config_name

sasl_default_realm

Type:

string

Default:

''

SASL realm to use if no realm present in username

connection_retry_interval

Type:

integer

Default:

1

Minimum Value:

1

Seconds to pause before attempting to re-connect.

connection_retry_backoff

Type:

integer

Default:

2

Minimum Value:

0

Increase the connection_retry_interval by this many seconds after each unsuccessful failover attempt.

connection_retry_interval_max

Type:

integer

Default:

30

Minimum Value:

1

Maximum limit for connection_retry_interval + connection_retry_backoff

link_retry_delay

Type:

integer

Default:

10

Minimum Value:

1

Time to pause between re-connecting an AMQP 1.0 link that failed due to a recoverable error.

default_reply_retry

Type:

integer

Default:

0

Minimum Value:

-1

The maximum number of attempts to re-send a reply message which failed due to a recoverable error.

default_reply_timeout

Type:

integer

Default:

30

Minimum Value:

5

The deadline for an rpc reply message delivery.

default_send_timeout

Type:

integer

Default:

30

Minimum Value:

5

The deadline for an rpc cast or call message delivery. Only used when caller does not provide a timeout expiry.

default_notify_timeout

Type:

integer

Default:

30

Minimum Value:

5

The deadline for a sent notification message delivery. Only used when caller does not provide a timeout expiry.

default_sender_link_timeout

Type:

integer

Default:

600

Minimum Value:

1

The duration to schedule a purge of idle sender links. Detach link after expiry.

addressing_mode

Type:

string

Default:

dynamic

Indicates the addressing mode used by the driver. Permitted values: ‘legacy’ - use legacy non-routable addressing ‘routable’ - use routable addresses ‘dynamic’ - use legacy addresses if the message bus does not support routing otherwise use routable addressing

pseudo_vhost

Type:

boolean

Default:

True

Enable virtual host support for those message buses that do not natively support virtual hosting (such as qpidd). When set to true the virtual host name will be added to all message bus addresses, effectively creating a private ‘subnet’ per virtual host. Set to False if the message bus supports virtual hosting using the ‘hostname’ field in the AMQP 1.0 Open performative as the name of the virtual host.

server_request_prefix

Type:

string

Default:

exclusive

address prefix used when sending to a specific server

Deprecated Variations

Group	Name
amqp1	server_request_prefix

broadcast_prefix

Type:

string

Default:

broadcast

address prefix used when broadcasting to all servers

Deprecated Variations

Group	Name
amqp1	broadcast_prefix

group_request_prefix

Type:

string

Default:

unicast

address prefix when sending to any server in group

Deprecated Variations

Group	Name
amqp1	group_request_prefix

rpc_address_prefix

Type:

string

Default:

openstack.org/om/rpc

Address prefix for all generated RPC addresses

notify_address_prefix

Type:

string

Default:

openstack.org/om/notify

Address prefix for all generated Notification addresses

multicast_address

Type:

string

Default:

multicast

Appended to the address prefix when sending a fanout message. Used by the message bus to identify fanout messages.

unicast_address

Type:

string

Default:

unicast

Appended to the address prefix when sending to a particular RPC/Notification server. Used by the message bus to identify messages sent to a single destination.

anycast_address

Type:

string

Default:

anycast

Appended to the address prefix when sending to a group of consumers. Used by the message bus to identify messages that should be delivered in a round-robin fashion across consumers.

default_notification_exchange

Type:

string

Default:

<None>

Exchange name used in notification addresses. Exchange name resolution precedence: Target.exchange if set else default_notification_exchange if set else control_exchange if set else ‘notify’

default_rpc_exchange

Type:

string

Default:

<None>

Exchange name used in RPC addresses. Exchange name resolution precedence: Target.exchange if set else default_rpc_exchange if set else control_exchange if set else ‘rpc’

reply_link_credit

Type:

integer

Default:

200

Minimum Value:

1

Window size for incoming RPC Reply messages.

rpc_server_credit

Type:

integer

Default:

100

Minimum Value:

1

Window size for incoming RPC Request messages

notify_server_credit

Type:

integer

Default:

100

Minimum Value:

1

Window size for incoming Notification messages

pre_settled

Type:

multi-valued

Default:

rpc-cast

Default:

rpc-reply

Send messages of this type pre-settled. Pre-settled messages will not receive acknowledgement from the peer. Note well: pre-settled messages may be silently discarded if the delivery fails. Permitted values: ‘rpc-call’ - send RPC Calls pre-settled ‘rpc-reply’- send RPC Replies pre-settled ‘rpc-cast’ - Send RPC Casts pre-settled ‘notify’ - Send Notifications pre-settled

oslo_messaging_kafka

kafka_max_fetch_bytes

Type:

integer

Default:

1048576

Max fetch bytes of Kafka consumer

kafka_consumer_timeout

Type:

floating point

Default:

1.0

Default timeout(s) for Kafka consumers

pool_size

Type:

integer

Default:

10

Pool Size for Kafka Consumers

Warning

This option is deprecated for removal. Its value may be silently ignored in the future.

Reason:

Driver no longer uses connection pool.

conn_pool_min_size

Type:

integer

Default:

2

The pool size limit for connections expiration policy

Warning

This option is deprecated for removal. Its value may be silently ignored in the future.

Reason:

Driver no longer uses connection pool.

conn_pool_ttl

Type:

integer

Default:

1200

The time-to-live in sec of idle connections in the pool

Warning

This option is deprecated for removal. Its value may be silently ignored in the future.

Reason:

Driver no longer uses connection pool.

consumer_group

Type:

string

Default:

oslo_messaging_consumer

Group id for Kafka consumer. Consumers in one group will coordinate message consumption

producer_batch_timeout

Type:

floating point

Default:

0.0

Upper bound on the delay for KafkaProducer batching in seconds

producer_batch_size

Type:

integer

Default:

16384

Size of batch for the producer async send

compression_codec

Type:

string

Default:

none

Valid Values:

none, gzip, snappy, lz4, zstd

The compression codec for all data generated by the producer. If not set, compression will not be used. Note that the allowed values of this depend on the kafka version

enable_auto_commit

Type:

boolean

Default:

False

Enable asynchronous consumer commits

max_poll_records

Type:

integer

Default:

500

The maximum number of records returned in a poll call

security_protocol

Type:

string

Default:

PLAINTEXT

Valid Values:

PLAINTEXT, SASL_PLAINTEXT, SSL, SASL_SSL

Protocol used to communicate with brokers

sasl_mechanism

Type:

string

Default:

PLAIN

Mechanism when security protocol is SASL

ssl_cafile

Type:

string

Default:

''

CA certificate PEM file used to verify the server certificate

ssl_client_cert_file

Type:

string

Default:

''

Client certificate PEM file used for authentication.

ssl_client_key_file

Type:

string

Default:

''

Client key PEM file used for authentication.

ssl_client_key_password

Type:

string

Default:

''

Client key password file used for authentication.

oslo_messaging_notifications

driver

Type:

multi-valued

Default:

''

The Drivers(s) to handle sending notifications. Possible values are messaging, messagingv2, routing, log, test, noop

Deprecated Variations

Group	Name
DEFAULT	notification_driver

transport_url

Type:

string

Default:

<None>

A URL representing the messaging driver to use for notifications. If not set, we fall back to the same configuration used for RPC.

Deprecated Variations

Group	Name
DEFAULT	notification_transport_url

topics

Type:

list

Default:

['notifications']

AMQP topic used for OpenStack notifications.

Deprecated Variations

Group	Name
rpc_notifier2	topics
DEFAULT	notification_topics

retry

Type:

integer

Default:

-1

The maximum number of attempts to re-send a notification message which failed to be delivered due to a recoverable error. 0 - No retry, -1 - indefinite

oslo_messaging_rabbit

amqp_durable_queues

Type:

boolean

Default:

False

Use durable queues in AMQP. If rabbit_quorum_queue is enabled, queues will be durable and this value will be ignored.

amqp_auto_delete

Type:

boolean

Default:

False

Auto-delete queues in AMQP.

Deprecated Variations

Group	Name
DEFAULT	amqp_auto_delete

ssl

Type:

boolean

Default:

False

Connect over SSL.

Deprecated Variations

Group	Name
oslo_messaging_rabbit	rabbit_use_ssl

ssl_version

Type:

string

Default:

''

SSL version to use (valid only if SSL enabled). Valid values are TLSv1 and SSLv23. SSLv2, SSLv3, TLSv1_1, and TLSv1_2 may be available on some distributions.

Deprecated Variations

Group	Name
oslo_messaging_rabbit	kombu_ssl_version

ssl_key_file

Type:

string

Default:

''

SSL key file (valid only if SSL enabled).

Deprecated Variations

Group	Name
oslo_messaging_rabbit	kombu_ssl_keyfile

ssl_cert_file

Type:

string

Default:

''

SSL cert file (valid only if SSL enabled).

Deprecated Variations

Group	Name
oslo_messaging_rabbit	kombu_ssl_certfile

ssl_ca_file

Type:

string

Default:

''

SSL certification authority file (valid only if SSL enabled).

Deprecated Variations

Group	Name
oslo_messaging_rabbit	kombu_ssl_ca_certs

ssl_enforce_fips_mode

Type:

boolean

Default:

False

Global toggle for enforcing the OpenSSL FIPS mode. This feature requires Python support. This is available in Python 3.9 in all environments and may have been backported to older Python versions on select environments. If the Python executable used does not support OpenSSL FIPS mode, an exception will be raised.

heartbeat_in_pthread

Type:

boolean

Default:

False

(DEPRECATED) It is recommend not to use this option anymore. Run the health check heartbeat thread through a native python thread by default. If this option is equal to False then the health check heartbeat will inherit the execution model from the parent process. For example if the parent process has monkey patched the stdlib by using eventlet/greenlet then the heartbeat will be run through a green thread. This option should be set to True only for the wsgi services.

Warning

This option is deprecated for removal. Its value may be silently ignored in the future.

Reason:

The option is related to Eventlet which will be removed. In addition this has never worked as expected with services using eventlet for core service framework.

kombu_reconnect_delay

Type:

floating point

Default:

1.0

Minimum Value:

0.0

Maximum Value:

4.5

How long to wait (in seconds) before reconnecting in response to an AMQP consumer cancel notification.

Deprecated Variations

Group	Name
DEFAULT	kombu_reconnect_delay

kombu_compression

Type:

string

Default:

<None>

EXPERIMENTAL: Possible values are: gzip, bz2. If not set compression will not be used. This option may not be available in future versions.

kombu_missing_consumer_retry_timeout

Type:

integer

Default:

60

How long to wait a missing client before abandoning to send it its replies. This value should not be longer than rpc_response_timeout.

Deprecated Variations

Group	Name
oslo_messaging_rabbit	kombu_reconnect_timeout

kombu_failover_strategy

Type:

string

Default:

round-robin

Valid Values:

round-robin, shuffle

Determines how the next RabbitMQ node is chosen in case the one we are currently connected to becomes unavailable. Takes effect only if more than one RabbitMQ node is provided in config.

rabbit_login_method

Type:

string

Default:

AMQPLAIN

Valid Values:

PLAIN, AMQPLAIN, EXTERNAL, RABBIT-CR-DEMO

The RabbitMQ login method.

Deprecated Variations

Group	Name
DEFAULT	rabbit_login_method

rabbit_retry_interval

Type:

integer

Default:

1

How frequently to retry connecting with RabbitMQ.

rabbit_retry_backoff

Type:

integer

Default:

2

How long to backoff for between retries when connecting to RabbitMQ.

Deprecated Variations

Group	Name
DEFAULT	rabbit_retry_backoff

rabbit_interval_max

Type:

integer

Default:

30

Maximum interval of RabbitMQ connection retries. Default is 30 seconds.

rabbit_ha_queues

Type:

boolean

Default:

False

Try to use HA queues in RabbitMQ (x-ha-policy: all). If you change this option, you must wipe the RabbitMQ database. In RabbitMQ 3.0, queue mirroring is no longer controlled by the x-ha-policy argument when declaring a queue. If you just want to make sure that all queues (except those with auto-generated names) are mirrored across all nodes, run: “rabbitmqctl set_policy HA ‘^(?!amq.).*’ ‘{“ha-mode”: “all”}’ “

Deprecated Variations

Group	Name
DEFAULT	rabbit_ha_queues

rabbit_quorum_queue

Type:

boolean

Default:

False

Use quorum queues in RabbitMQ (x-queue-type: quorum). The quorum queue is a modern queue type for RabbitMQ implementing a durable, replicated FIFO queue based on the Raft consensus algorithm. It is available as of RabbitMQ 3.8.0. If set this option will conflict with the HA queues (rabbit_ha_queues) aka mirrored queues, in other words the HA queues should be disabled. Quorum queues are also durable by default so the amqp_durable_queues option is ignored when this option is enabled.

rabbit_transient_quorum_queue

Type:

boolean

Default:

False

Use quorum queues for transients queues in RabbitMQ. Enabling this option will then make sure those queues are also using quorum kind of rabbit queues, which are HA by default.

rabbit_quorum_delivery_limit

Type:

integer

Default:

0

Each time a message is redelivered to a consumer, a counter is incremented. Once the redelivery count exceeds the delivery limit the message gets dropped or dead-lettered (if a DLX exchange has been configured) Used only when rabbit_quorum_queue is enabled, Default 0 which means dont set a limit.

rabbit_quorum_max_memory_length

Type:

integer

Default:

0

By default all messages are maintained in memory if a quorum queue grows in length it can put memory pressure on a cluster. This option can limit the number of messages in the quorum queue. Used only when rabbit_quorum_queue is enabled, Default 0 which means dont set a limit.

Deprecated Variations

Group	Name
oslo_messaging_rabbit	rabbit_quroum_max_memory_length

rabbit_quorum_max_memory_bytes

Type:

integer

Default:

0

By default all messages are maintained in memory if a quorum queue grows in length it can put memory pressure on a cluster. This option can limit the number of memory bytes used by the quorum queue. Used only when rabbit_quorum_queue is enabled, Default 0 which means dont set a limit.

Deprecated Variations

Group	Name
oslo_messaging_rabbit	rabbit_quroum_max_memory_bytes

rabbit_transient_queues_ttl

Type:

integer

Default:

1800

Minimum Value:

0

Positive integer representing duration in seconds for queue TTL (x-expires). Queues which are unused for the duration of the TTL are automatically deleted. The parameter affects only reply and fanout queues. Setting 0 as value will disable the x-expires. If doing so, make sure you have a rabbitmq policy to delete the queues or you deployment will create an infinite number of queue over time.In case rabbit_stream_fanout is set to True, this option will control data retention policy (x-max-age) for messages in the fanout queue rather then the queue duration itself. So the oldest data in the stream queue will be discarded from it once reaching TTL Setting to 0 will disable x-max-age for stream which make stream grow indefinitely filling up the diskspace

rabbit_qos_prefetch_count

Type:

integer

Default:

0

Specifies the number of messages to prefetch. Setting to zero allows unlimited messages.

heartbeat_timeout_threshold

Type:

integer

Default:

60

Number of seconds after which the Rabbit broker is considered down if heartbeat’s keep-alive fails (0 disables heartbeat).

heartbeat_rate

Type:

integer

Default:

3

How often times during the heartbeat_timeout_threshold we check the heartbeat.

direct_mandatory_flag

Type:

boolean

Default:

True

(DEPRECATED) Enable/Disable the RabbitMQ mandatory flag for direct send. The direct send is used as reply, so the MessageUndeliverable exception is raised in case the client queue does not exist.MessageUndeliverable exception will be used to loop for a timeout to lets a chance to sender to recover.This flag is deprecated and it will not be possible to deactivate this functionality anymore

Warning

This option is deprecated for removal. Its value may be silently ignored in the future.

Reason:

Mandatory flag no longer deactivable.

enable_cancel_on_failover

Type:

boolean

Default:

False

Enable x-cancel-on-ha-failover flag so that rabbitmq server will cancel and notify consumerswhen queue is down

use_queue_manager

Type:

boolean

Default:

False

Should we use consistant queue names or random ones

hostname

Type:

string

Default:

node1.example.com

This option has a sample default set, which means that its actual default value may vary from the one documented above.

Hostname used by queue manager. Defaults to the value returned by socket.gethostname().

processname

Type:

string

Default:

nova-api

This option has a sample default set, which means that its actual default value may vary from the one documented above.

Process name used by queue manager

rabbit_stream_fanout

Type:

boolean

Default:

False

Use stream queues in RabbitMQ (x-queue-type: stream). Streams are a new persistent and replicated data structure (“queue type”) in RabbitMQ which models an append-only log with non-destructive consumer semantics. It is available as of RabbitMQ 3.9.0. If set this option will replace all fanout queues with only one stream queue.

API

oslo_messaging.opts.list_opts()

Return a list of oslo.config options available in the library.

The returned list includes all oslo.config options which may be registered at runtime by the library.

Each element of the list is a tuple. The first element is the name of the group under which the list of elements in the second element will be registered. A group name of None corresponds to the [DEFAULT] group in config files.

This function is also discoverable via the ‘oslo_messaging’ entry point under the ‘oslo.config.opts’ namespace.

The purpose of this is to allow tools like the Oslo sample config file generator to discover the options exposed to users by this library.

Returns:

a list of (group_name, opts) tuples