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.

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

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.

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

heartbeat_in_pthread

Type

boolean

Default

False

EXPERIMENTAL: Run the health check heartbeat thread through a native python thread. By default if this option isn’t provided the health check heartbeat will inherit the execution model from the parent process. By example if the parent process have monkey patched the stdlib by using eventlet/greenlet then the heartbeat will be run through a green thread.

kombu_reconnect_delay

Type

floating point

Default

1.0

How long to wait 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, 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_transient_queues_ttl

Type

integer

Default

1800

Minimum Value

1

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.

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

2

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

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