RabbitMQ Releases

RabbitMQ 4.3.4 is a maintenance release in the 4.3.x release series . It is strongly recommended that you read 4.3.0 release notes in detail if upgrading from a version prior to 4.3.0 . Minimum Supported Erlang Version The minimum supported Erlang version for this release series is 27.0 . RabbitMQ and Erlang/OTP Compatibility Matrix has more details on Erlang version requirements for RabbitMQ. Nodes will fail to start on older Erlang releases. Changes Worth Mentioning Release notes can be found on GitHub at rabbitmq-server/release-notes . Core Server Bug Fixes Quorum queues in clusters upgraded from 3.13.x to 4.2.x and then to 4.3.x could stop emitting metrics and taking snapshots after a node restart. GitHub issues: #16974 , #16990 The AMQP 1.0 parser now detects standard message body sections more strictly. GitHub issue: #17017 The AMQP 1.0 parser now decodes certain array values more efficiently. GitHub issue: #16994 Stream Plugin Bug Fixes The single active consumer coordinator did not notify a consumer that was re-selected for activation while it was still deactivating, leaving the group without an active consumer. Contributed by @pterygota . GitHub issues: #16975 , #16976 Management Plugin Bug Fixes Very short lived exclusive queues could cause an exception during metric collection, producing log noise. GitHub issues: #16989 , #16999 , #17002 After an IdP-initiated OAuth 2 login, the management UI now returns the user to the page that was open before the login instead of the default one. Contributed by @thisisnsh . GitHub issues: #16957 , #16961 Several security fixes and validation gaps were addressed: The HTTP API now returns 404 Not Found instead of 401 Unauthorized when a user lacks permission to a vhost, avoiding disclosure of the vhost's existence. Token expiry values that use a floating point number are now accepted, not just integers. To access all user-limits it is required administrator priviledge To access a user-limits for a specific user now require the requester to be that same user or have administrator/monitoring privileges. GitHub issue: #16709 Enhancements The management UI Content Security Policy (CSP) no longer includes the unsafe-eval and unsafe-inline directives. GitHub issue: #16916 Federation Plugin Bug Fixes In scenarios that involved a federated queue and a federated exchange with exactly the same name in the same virtual host, deleting an upstream unintentionally corrupted the federated exchange(s) operating state, breaking federation for the exchange in question. GitHub issues: #16991 , #16997 Dependency Changes None in this release.

RabbitMQ 4.3.5 is a maintenance release in the 4.3.x release series . It is strongly recommended that you read 4.3.0 release notes in detail if upgrading from a version prior to 4.3.0 . Minimum Supported Erlang Version The minimum supported Erlang version for this release series is 27.0 . RabbitMQ and Erlang/OTP Compatibility Matrix has more details on Erlang version requirements for RabbitMQ. Nodes will fail to start on older Erlang releases. Changes Worth Mentioning Release notes can be found on GitHub at rabbitmq-server/release-notes . Core Server Bug Fixes With direct reply-to , a message routed to multiple targets that resolved to the same process could be delivered to it more than once. GitHub issue: #17071 Quorum queue recovery from a recovery checkpoint could leave a part of the queue's internal state only partially initialized. GitHub issue: #17012 In clusters that run a mix of 4.2.x and 4.3.x nodes during a rolling upgrade, local quorum queue queries now fall back to the previous state machine version instead of failing. GitHub issue: #17128 A malformed AMQP 1.0 frame now results in a framing error returned to the client instead of an exception. GitHub issue: #17101 The AMQP 1.0 message parser now validates message sections more strictly and decodes certain types of arrays more efficiently. GitHub issue: #17049 Topic exchanges now limit the number of multi-segment ( # ) wildcards a binding key can use to two. The # wildcard is meant to be used as the final segment, that is, just once. GitHub issue: #17039 When connection credentials are refreshed (for example, when an OAuth 2 token is renewed), the user's tags are now updated instead of being carried over from the original state. GitHub issue: #17029 Definition import from an HTTPS endpoint no longer fails when a password-protected TLS (HTTPS) client certificate is used. Contributed by @Pyolar . GitHub issue: #16973 The AMQP 1.0 Erlang client no longer logs an exception when a link is already detached. Workloads that use short lived links could produce a substantial amount of log noise. GitHub issue: #17124 Enhancements Authentication events are now logged under a new logging category, user . Successful logins are logged at the info level, failed login attempts at the warning level. GitHub issue: #16907 CLI Tools Enhancements rabbitmqctl hash_password now supports more password hashing functions. GitHub issues: #14215 , #17108 Stream Plugin Bug Fixes A stream protocol connection can have at most 256 publishers and 256 subscriptions, a limit that comes from the protocol's wire format. Attempts to go over these limits are now rejected early with a clear error instead of failing later with an unrelated one. GitHub issue: #17123 Enhancements Before a stream client connection completes authentication and authorization (that is, before a successful open ), the server now enforces a low frame_max ceiling instead of the full configured value. The default, 8192 bytes, is high enough to accommodate realistic JWT tokens used with SASL PLAIN authentication, and mirrors a mechanism already in place for AMQP 0-9-1 connections. It can be adjusted with the new stream.initial_frame_max setting. GitHub issue: #17053 New setting: stream.max_uncompressed_sub_entry_batch_size . It bounds the declared uncompressed size of a published sub-entry batch, and defaults to 67108864 (64 MiB), the same default already used by the Java client's maxUncompressedSubEntryBatchSize . The broker and any client publishing to it should be configured with the same value. GitHub issue: #17103 Management Plugin Bug Fixes HTTP API endpoints that accept a node name, including the federation and tracing related ones, now validate that the target node is a cluster member. GitHub issues: #17106 , #17118 The management UI no longer displays certain alert messages twice. GitHub issue: #17127 Enhancements When management.credential_encryption_secret is configured, the management UI login endpoint ( POST /api/login ) returns client credentials encrypted using AES-256-GCM with a key derived from the configured secret, and returns the ciphertext as an opaque token prefixed with rmqe. . The browser stores this token and presents it on all subsequent requests using the Authorization: Bearer rmqe.<token> header. The secret MUST be identical on every node in the cluster. Important : during a rolling cluster upgrade, enable this feature only after all nodes have been upgraded. This is particularly important for clusters behind a load balancer: nodes that run older versions will not recognize the encrypted tokens and will reject the requests, unexpectedly logging users out. GitHub issue: #16705 GET /api/definitions now supports conditional requests ( ETag ). The ETag value is derived from the metadata store Raft index, so the tag will naturally change as the metadata store serves writes. GitHub issues: #16724 , #17121 The Referrer-Policy HTTP response header can now be configured with the management.headers.referrer_policy setting. GitHub issue: #16893 When management.http.hide_allow_header is set to true , the Allow HTTP response header is omitted from all responses except 405 Method Not Allowed ones, where it is required by the HTTP specification. This avoids disclosing the supported HTTP methods to clients. GitHub issue: #16893 When management.definitions.require_json_extension is set to true , both the management UI and the HTTP API will reject definition upload where the file does not have a .json extension. The setting defaults to false . Regardless of this setting, the server always validates that the uploaded content is valid JSON before importing it. GitHub issue: #16946 OAuth 2 AuthN and AuthZ Backend Plugin Bug Fixes When RabbitMQ is behind a proxy that terminates TLS, the OAuth 2 login flow now honors the X-Forwarded-Proto , X-Forwarded-Host and X-Forwarded-Port headers when rewriting the token endpoint URL in the OpenID discovery payload. GitHub issue: #17153 Shovel Plugin Bug Fixes Reduced log noise. GitHub issue: #17028 Static shovels that do not define any declarations failed to start. GitHub issues: #17063 , #17067 When a topology setup failure stops a shovel worker, the specific reason is now reported instead of a generic one. GitHub issue: #17135 The Shovel HTTP API now processes shovel URIs the same way the federation plugin processes its upstream URIs. GitHub issue: #17134 Enhancements Shovel TTL: dynamic shovels support a new setting, src-delete-after-duration , that instructs the shovel to self-delete after at least the specified duration. Contributed by @michalovits . GitHub issues: #17055 , #17064 Federation Plugin Bug Fixes A malformed upstream URI could prevent a federation link from starting even when other, well-formed URIs were available. All candidate URIs are now tried. Contributed by @sauravonwww . GitHub issue: #17046 MQTT Plugin Bug Fixes Packets split across many network fragments are now parsed more efficiently. GitHub issue: #17093 MQTT 5.0 properties are now parsed strictly: a property that is not valid for a given packet type is rejected. GitHub issue: #17039 A Receive Maximum value of 0, prohibited by the MQTT 5.0 specification, is now rejected. GitHub issue: #17035 STOMP Plugin Bug Fixes Frame size limits are now enforced earlier in the connection lifecycle. GitHub issue: #17116 Web STOMP Plugin Bug Fixes The accumulated frame size is now checked against max_frame_size after a connection has authenticated, matching the behavior of "regular" STOMP connections. GitHub issue: #17065 Consistent Hash Exchange Plugin Bug Fixes An edge case in bucket selection is now handled gracefully. GitHub issue: #17081 Dependency Changes cowboy was upgraded to 2.18.0 cowlib was upgraded to 2.19.0 gun was upgraded to 2.5.0 ra was upgraded to 3.1.10 ranch was upgraded to 2.2.1

RabbitMQ 4.3.3 is a maintenance release in the 4.3.x release series . It is strongly recommended that you read 4.3.0 release notes in detail if upgrading from a version prior to 4.3.0 . Minimum Supported Erlang Version Important : starting with this release, the minimum supported Erlang version is 27.0 . Erlang/OTP 26 has reached end of life and is no longer supported. GitHub issue: #16914 RabbitMQ and Erlang/OTP Compatibility Matrix has more details on Erlang version requirements for RabbitMQ. Nodes will fail to start on older Erlang releases. Changes Worth Mentioning Release notes can be found on GitHub at rabbitmq-server/release-notes . Core Server Bug Fixes Quorum queue, Khepri and other Raft leaders could optimistically commit new log entries in certain scenarios. GitHub issue: rabbitmq/ra#637 Quorum queues that use at-least-once dead lettering could get their dead lettering process permanently stuck after repeated queue membership changes. GitHub issue: #16652 Classic queue index directory paths could accumulate slashes, eventually failing with an enametoolong file system error. GitHub issue: #16833 Enabling the tie_binding_to_dest_with_keep_while_cond feature flag could fail with an exception when certain exchange-to-exchange topologies. GitHub issue: #16824 An invalid consumer_timeout value in the configuration now falls back to the default value (24 hours) instead of being used as is. GitHub issue: #16799 AMQP 1.0 management operations that declare an exchange with an alternate exchange now verify the necessary permissions on the alternate exchange, matching AMQP 0-9-1. GitHub issue: #16785 AMQP 1.0 management GET /bindings operations now behave consistently with the rest of the binding-related handlers. GitHub issue: #16790 Worker pool processes no longer terminate when they receive an unexpected message. Contributed by @Ayanda-D . GitHub issue: #16666 A race condition between concurrent queue (or virtual host) deletion and a Ra cluster shutdown could log an exception. Contributed by @Ayanda-D . GitHub issue: #16880 A closing channel (connection) that failed to send channel.close_ok on an already terminated writer or socket no longer produce log noise. Contributed by @Ayanda-D . GitHub issue: #16651 Unexpected failures during channel termination cleanup no longer produce log noise. Contributed by @Ayanda-D . GitHub issue: #16740 Code paths that use rabbit_queue_type_util:erpc_call/5 now handle more errors. Contributed by @Ayanda-D . GitHub issue: #16701 Nodes could fail to start with a bad_generator exception in rabbit_queue_decorator:select/1 when a quorum queue record in the metadata store had its decorators set to undefined . GitHub issues: #16843 , #16844 Enabling tracing on multiple virtual hosts concurrently could silently drop some of the virtual hosts from the traced set. All virtual host tracing state modifications are now linearized. GitHub issues: #16755 , #16763 Enhancements Password salts are now generated using a cryptographically secure pseudo-random number generator (CSPRNG). GitHub issue: #16775 Socket-level metric collection used by several protocol readers and the management agent now handles concurrently closed connections safely. Inspired by a contribution of @MugemaneBertin2001 . GitHub issues: #16856 , #16832 CLI Tools Bug Fixes rabbitmq-plugins commands now tolerate plugins that are listed as enabled but are not installed. GitHub issue: #16896 rabbitmq-plugins list no longer outputs an empty plugin table when the target node cannot be reached. GitHub issue: #16791 rabbitmq-plugins commands now correctly handle file paths of remote nodes, validate remote nodes in offline mode, and no longer report false positives for rabbitmq-plugins is_enabled . GitHub issue: #16842 Shell (Bash, zsh) command completion fixes. Contributed by @Chr1s70ph . GitHub issue: #16776 Enhancements rabbitmq-queues and rabbitmq-streams now provide transfer_leadership commands for individual queues and streams. GitHub issue: #16757 rabbitmq-upgrade drain safety improvements: the command now handles certain failures more gracefully. Proposed by @MugemaneBertin2001 . GitHub issues: #16865 , #3369 Stream Plugin Bug Fixes Permissions required for certain stream protocol operations were adjusted to be consistent with comparable operations over other protocols. GitHub issue: #16754 Enhancements The maximum number of super stream partitions is now limited to 1,000 partitions by default. This limit can be increased using the stream.max_super_stream_partitions key in rabbitmq.conf . GitHub issues: #16689 , #16706 A client RPC timeout is now logged as a concise message instead of an exception with a stack trace. Contributed by @MugemaneBertin2001 . GitHub issues: #16829 , #15744 Management Plugin Bug Fixes OAuth 2 login could fail in Safari. A new token endpoint proxy is now used for the affected authorization flow. GitHub issues: #16664 , #16892 Several management UI templates now use safe string escaping in more places. GitHub issue: #16738 , #16677 HTTP API message publishing endpoint now uses a timeout when waiting for publisher confirms. GitHub issue: #16911 Enhancements Definition export over the HTTP API is now significantly more efficient and transfers the result using HTTP response streaming. GitHub issue: #16734 The Referrer-Policy HTTP response header is now set (and configurable). GitHub issue: #16893 The Allow HTTP response header can now be excluded from HTTP API responses. GitHub issue: #16907 HTTP API error responses were refactored to be more consistent and expose fewer internal details. GitHub issue: #16709 HTTP access log entries for OAuth 2-authenticated requests now use the username determined by the authentication backend (e.g. preferred_username ) instead of the client ID. GitHub issues: #16879 , #16559 Definition file uploads via the management UI now require a .json file extension (enabled via a feature switch). GitHub issue: #16946 OAuth 2 AuthN and AuthZ Backend Plugin Bug Fixes Fractional exp (token expiry) timestamp values are now honored. GitHub issue: #16713 Enhancements The token refresh path is now more robust. GitHub issue: #16858 Shovel Plugin Bug Fixes Several shovel bug fixes, including one for static shovel URIs whose credentials could be logged. GitHub issues: #16855 , #16835 A shovel deleted before it successfully connected (in the starting state) no longer leaks its status entry. GitHub issue: #16767 Improved network failure recovery for shovels. GitHub issue: #16662 Enhancements Shovels with AMQP 1.0 sources now support the src-consumer-args parameter. GitHub issue: #16800 Federation Plugin Bug Fixes Federation upstream URIs are now validated more strictly. GitHub issue: #16942 Improved network failure recovery for shovels. GitHub issue: #16662 Exchange federation links now trap exits later in the initialization process, avoiding confusing timeouts and log noise. GitHub issue: #16801 MQTT Plugin Enhancements More correct peer host detection in setups that have Proxy Protocol enabled. GitHub issue: #16933 STOMP Plugin Enhancements Internal socket handling refactoring shared by STOMP and Web STOMP connections. GitHub issue: #16935 Web MQTT Plugin Enhancements More correct peer host detection in setups that have Proxy Protocol enabled. GitHub issue: #16933 The HSTS response header policy can now be configured for Web MQTT listeners. GitHub issues: #14161 , #16772 Web STOMP Plugin Enhancements More correct peer host detection in setups that have Proxy Protocol enabled. GitHub issue: #16933 The HSTS response header policy can now be configured for Web STOMP listeners. GitHub issues: #14161 , #16772 LDAP AuthN and AuthZ Backend Plugin Bug Fixes Additional DN escaping (RFC 4514) improvements GitHub issue: #16712 JMS Topic Exchange Plugin Enhancements JMS selector evaluation now uses much smaller, safer limits. GitHub issue: #16951 AWS Peer Discovery Plugin Bug Fixes Fixed a SigV4 request signing issue ( SignatureDoesNotMatch ) for body-less requests such as S3 GET s. Contributed by @sdewhitt . GitHub issue: #16759 Dependency Changes ra was upgraded to 3.1.9 cowboy was upgraded to 2.17.0

RabbitMQ 4.2.9 is a maintenance release in the 4.2.x release series . It is strongly recommended that you read 4.2.0 release notes in detail if upgrading from a version prior to 4.2.0 . Minimum Supported Erlang Version Important : starting with this release, the minimum supported Erlang version is 27.0 . Erlang/OTP 26 has reached end of life and is no longer supported. GitHub issue: #16914 RabbitMQ and Erlang/OTP Compatibility Matrix has more details on Erlang version requirements for RabbitMQ. Nodes will fail to start on older Erlang releases. Changes Worth Mentioning Release notes can be found on GitHub at rabbitmq-server/release-notes . Core Server Bug Fixes Classic queue index directory paths could accumulate slashes, eventually failing with an enametoolong file system error. GitHub issue: #16833 AMQP 1.0 management operations that declare an exchange with an alternate exchange now verify the necessary permissions on the alternate exchange, matching AMQP 0-9-1. GitHub issue: #16785 AMQP 1.0 management GET /bindings operations now behave consistently with the rest of the binding-related handlers. GitHub issue: #16790 Worker pool processes no longer terminate when they receive an unexpected message. Contributed by @Ayanda-D . GitHub issue: #16666 A race condition between concurrent queue (or virtual host) deletion and a Ra cluster shutdown could log an exception. Contributed by @Ayanda-D . GitHub issue: #16880 A closing channel (connection) that failed to send channel.close_ok on an already terminated writer or socket no longer produce log noise. Contributed by @Ayanda-D . GitHub issue: #16651 Unexpected failures during channel termination cleanup no longer produce log noise. Contributed by @Ayanda-D . GitHub issue: #16740 Code paths that use rabbit_queue_type_util:erpc_call/5 now handle more errors. Contributed by @Ayanda-D . GitHub issue: #16701 Nodes could fail to start with a bad_generator exception in rabbit_queue_decorator:select/1 when a quorum queue record in the metadata store had its decorators set to undefined . GitHub issues: #16843 , #16844 Enabling tracing on multiple virtual hosts concurrently could silently drop some of the virtual hosts from the traced set. All virtual host tracing state modifications are now linearized. GitHub issues: #16755 , #16763 Enhancements Password salts are now generated using a cryptographically secure pseudo-random number generator (CSPRNG). GitHub issue: #16775 Socket-level metric collection used by several protocol readers and the management agent now handles concurrently closed connections safely. Inspired by a contribution of @MugemaneBertin2001 . GitHub issues: #16856 , #16832 CLI Tools Bug Fixes rabbitmq-plugins commands now tolerate plugins that are listed as enabled but are not installed. GitHub issue: #16896 rabbitmq-plugins list no longer outputs an empty plugin table when the target node cannot be reached. GitHub issue: #16791 rabbitmq-plugins commands now correctly handle file paths of remote nodes, validate remote nodes in offline mode, and no longer report false positives for rabbitmq-plugins is_enabled . GitHub issue: #16842 Shell (Bash, zsh) command completion fixes. Contributed by @Chr1s70ph . GitHub issue: #16776 Enhancements rabbitmq-queues and rabbitmq-streams now provide transfer_leadership commands for individual queues and streams. GitHub issue: #16757 rabbitmq-upgrade drain safety improvements: the command now handles certain failures more gracefully. Proposed by @MugemaneBertin2001 . GitHub issues: #16865 , #3369 Stream Plugin Bug Fixes Permissions required for certain stream protocol operations were adjusted to be consistent with comparable operations over other protocols. GitHub issue: #16754 Enhancements The maximum number of super stream partitions is now limited to 1,000 partitions by default. This limit can be increased using the stream.max_super_stream_partitions key in rabbitmq.conf . GitHub issues: #16689 , #16706 A client RPC timeout is now logged as a concise message instead of an exception with a stack trace. Contributed by @MugemaneBertin2001 . GitHub issues: #16829 , #15744 Management Plugin Bug Fixes OAuth 2 login could fail in Safari. A new token endpoint proxy is now used for the affected authorization flow. GitHub issues: #16664 , #16892 Several management UI templates now use safe string escaping in more places. GitHub issue: #16738 , #16677 HTTP API message publishing endpoint now uses a timeout when waiting for publisher confirms. GitHub issue: #16911 Enhancements Definition export over the HTTP API is now significantly more efficient and transfers the result using HTTP response streaming. GitHub issue: #16734 The Referrer-Policy HTTP response header is now set (and configurable). GitHub issue: #16893 HTTP API error responses were refactored to be more consistent and expose fewer internal details. GitHub issue: #16709 OAuth 2 AuthN and AuthZ Backend Plugin Bug Fixes Fractional exp (token expiry) timestamp values are now honored. GitHub issue: #16713 Enhancements The token refresh path is now more robust. GitHub issue: #16858 Shovel Plugin Bug Fixes Several shovel bug fixes, including one for static shovel URIs whose credentials could be logged. GitHub issues: #16855 , #16835 A shovel deleted before it successfully connected (in the starting state) no longer leaks its status entry. GitHub issue: #16767 Federation Plugin Bug Fixes Federation upstream URIs are now validated more strictly. GitHub issue: #16942 MQTT Plugin Enhancements More correct peer host detection in setups that have Proxy Protocol enabled. GitHub issue: #16933 Web MQTT Plugin Enhancements More correct peer host detection in setups that have Proxy Protocol enabled. GitHub issue: #16933 The HSTS response header policy can now be configured for Web MQTT listeners. GitHub issues: #14161 , #16772 STOMP Plugin Enhancements Internal socket handling refactoring shared by STOMP and Web STOMP connections. GitHub issue: #16935 Web STOMP Plugin Enhancements More correct peer host detection in setups that have Proxy Protocol enabled. GitHub issue: #16935 The HSTS response header policy can now be configured for Web STOMP listeners. GitHub issues: #14161 , #16772 LDAP AuthN and AuthZ Backend Plugin Bug Fixes Additional DN escaping (RFC 4514) improvements GitHub issue: #16712 JMS Topic Exchange Plugin Enhancements JMS selector evaluation now uses much smaller, safer limits. GitHub issue: #16951 AWS Peer Discovery Plugin Bug Fixes Fixed a SigV4 request signing issue ( SignatureDoesNotMatch ) for body-less requests such as S3 GET s. Contributed by @sdewhitt . GitHub issue: #16759 Dependency Changes cowboy was upgraded to 2.17.0

RabbitMQ 4.3.2 is a maintenance release in the 4.3.x release series . It is strongly recommended that you read 4.3.0 release notes in detail if upgrading from a version prior to 4.3.0 . Minimum Supported Erlang Version RabbitMQ and Erlang/OTP Compatibility Matrix has more details on Erlang version requirements for RabbitMQ. Nodes will fail to start on older Erlang releases. Changes Worth Mentioning Release notes can be found on GitHub at rabbitmq-server/release-notes . Core Server Bug Fixes Enabling the tie_binding_to_dest_with_keep_while_cond feature flag could fail in some rare cases. GitHub issue: #16587 Users created without a password or a password hash (for example, those that rely on X.509 certificate-based authentication) over the HTTP API are now stored correctly, exactly like the users whose password was cleared with rabbitmqctl clear_password . GitHub issues: #16629 , #16633 Consumer activity status of classic queue consumers was not always correctly updated and reported when single active consumer was enabled. GitHub issues: #16532 , #16450 The values of the x-consumer-timeout and x-consumer-disconnected-timeout optional arguments are now validated at queue declaration time. GitHub issue: #16557 Default queue type (DQT) validation now treats empty strings the same way as a missing value: by falling back. to the default (classic queues). GitHub issues: #16481 , #16488 Feature flag operations now avoid unnecessary work: flags that are already enabled on all cluster nodes are excluded from synchronization, and enabling an empty set of flags is a no-op. GitHub issue: #16497 Configuration changes for deprecated features are now honored when possible. GitHub issue: #16500 Enhancements The per-node channel limit ( channel_max_per_node ) is now also enforced for channels opened on direct Erlang client connections used by the Shovel and Federation plugins, matching the behavior enforced for "regular" AMQP 0-9-1 clients. GitHub issues: #16616 , #16618 Modules are now loaded in parallel early on node boot, reducing node startup time. GitHub issue: #16479 Several new rabbitmq.conf keys now supports encrypted values . GitHub issue: #16632 CLI Tools Bug Fixes rabbitmqctl set_topic_permissions now validates target user and exchange for existence. GitHub issue: #16590 rabbitmqctl add_vhost now validates the provided default queue type value. GitHub issue: #16481 Stream Plugin Bug Fixes Fixed a frame assembly performance regression in the stream protocol reader. GitHub issue: #16588 Enhancements Several stream protocol reader optimizations: stream metadata queries now contact cluster nodes concurrently, subscription lookups use a more efficient data structure, and frame processing short-circuits when a connection reaches a terminal state. GitHub issue: #16588 Management Plugin Bug Fixes CORS hardening: access-control-request-headers values are now validated and a wildcard ( * ) origin header value is rejected. GitHub issue: #16544 Definitions import now limits the size of multipart upload bodies, and definitions export download filenames are restricted to a safe character set. GitHub issue: #16544 HTTP API 500 responses no longer include internal error details in the response body. GitHub issue: #16544 Several HTTP response headers are now consistently lowercase, and a previously missing content-type header was added to certain responses. GitHub issue: #16544 Enhancements A one-time warning is now logged when the HSTS or CSP headers are disabled. GitHub issue: #16544 The timestamp of the oldest message in a stream is now displayed on the stream page. GitHub issue: #15412 The queue list page can now display a "Delayed" message count column, for example, for quorum queues that have a retry policy configured. GitHub issue: #16639 Prometheus Plugin Enhancements More plugin configuration keys, such as prometheus.ssl.password , now support encrypted values in rabbitmq.conf . GitHub issues: #16516 , #16521 MQTT Plugin Bug Fixes mqtt.tcp_listen_options.* settings in rabbitmq.conf did not take effect due to a configuration translation issue. GitHub issue: #16529 Dependency Changes cuttlefish was upgraded to 3.9.1 cowboy was upgraded to 2.16.0 cowlib was upgraded to 2.17.0 gun was upgraded to 2.4.0

RabbitMQ 4.2.8 is a maintenance release in the 4.2.x release series . It is strongly recommended that you read 4.2.0 release notes in detail if upgrading from a version prior to 4.2.0 . Minimum Supported Erlang Version RabbitMQ and Erlang/OTP Compatibility Matrix has more details on Erlang version requirements for RabbitMQ. Nodes will fail to start on older Erlang releases. Changes Worth Mentioning Release notes can be found on GitHub at rabbitmq-server/release-notes . Core Server Bug Fixes Users created without a password or a password hash (for example, those that rely on X.509 certificate-based authentication) over the HTTP API are now stored correctly, exactly like the users whose password was cleared with rabbitmqctl clear_password . GitHub issues: #16629 , #16633 Consumer activity status of classic queue consumers was not always correctly updated and reported when single active consumer was enabled. GitHub issues: #16532 , #16450 Default queue type (DQT) validation now treats empty strings the same way as a missing value: by falling back to the default (classic queues). GitHub issues: #16481 , #16488 Enhancements The per-node channel limit ( channel_max_per_node ) is now also enforced for channels opened on direct Erlang client connections used by the Shovel and Federation plugins, matching the behavior enforced for "regular" AMQP 0-9-1 clients. GitHub issues: #16616 , #16618 Modules are now loaded in parallel early on node boot, reducing node startup time. GitHub issue: #16479 Several new rabbitmq.conf keys now support encrypted values . GitHub issue: #16632 CLI Tools Bug Fixes rabbitmqctl add_vhost now validates the provided default queue type value. GitHub issue: #16481 Stream Plugin Bug Fixes Fixed a frame assembly performance regression in the stream protocol reader. GitHub issue: #16588 Enhancements Several stream protocol reader optimizations: stream metadata queries now contact cluster nodes concurrently, subscription lookups use a more efficient data structure, and frame processing short-circuits when a connection reaches a terminal state. GitHub issue: #16588 Management Plugin Bug Fixes CORS hardening: access-control-request-headers values are now validated and a wildcard ( * ) origin header value is rejected. GitHub issue: #16544 Definitions import now limits the size of multipart upload bodies, and definitions export download filenames are restricted to a safe character set. GitHub issue: #16544 HTTP API 500 responses no longer include internal error details in the response body. GitHub issue: #16544 Several HTTP response headers are now consistently lowercase, and a previously missing content-type header was added to certain responses. GitHub issue: #16544 Enhancements A one-time warning is now logged when the HSTS or CSP headers are disabled. GitHub issue: #16544 The timestamp of the oldest message in a stream is now displayed on the stream page. GitHub issue: #15412 Prometheus Plugin Enhancements More plugin configuration keys, such as prometheus.ssl.password , now support encrypted values in rabbitmq.conf . GitHub issues: #16516 , #16521 MQTT Plugin Bug Fixes mqtt.tcp_listen_options.* settings in rabbitmq.conf did not take effect due to a configuration translation issue. GitHub issue: #16529 Dependency Changes cuttlefish was upgraded to 3.9.1 cowboy was upgraded to 2.16.0 cowlib was upgraded to 2.17.0 gun was upgraded to 2.4.0

RabbitMQ 4.3.1 is a maintenance release in the 4.3.x release series . It is strongly recommended that you read 4.3.0 release notes in detail if upgrading from a version prior to 4.3.0 . Minimum Supported Erlang Version RabbitMQ and Erlang/OTP Compatibility Matrix has more details on Erlang version requirements for RabbitMQ. Nodes will fail to start on older Erlang releases. Changes Worth Mentioning Release notes can be found on GitHub at rabbitmq-server/release-notes . Core Server Bug Fixes If a queue was bound to a topic exchange using an empty binding key ( "" ), messages published to any topic exchange with an empty routing key would be incorrectly routed to that queue. To apply the fix, enable the new topic_binding_projection_v5 feature flag after upgrading all cluster nodes. GitHub issue: #16271 A virtual host could be falsely considered to be deleted in certain metadata store error and timeout scenarios. GitHub issue: #16422 Passive queue and exchange declarations are now allowed for users that have any permission on the virtual host ( configure , write , or read ), not only configure . GitHub issues: #16272 , #16085 Classic queue shared message store GC could fall behind other queue activity under heavy load GitHub issues: #16142 , #16141 Classic queue message store: garbage collection is now stopped cleanly during node shutdown. GitHub issue: #15498 Quorum queues now gracefully handle negative priority values. GitHub issue: #16280 Quorum queues: delayed retry-related policy keys are now accepted in policy definitions. GitHub issues: #16395 , #16398 Fixed a bug where quorum queue's at-least-once dead lettering could direct commands to the wrong member (replica). GitHub issue: #16203 Quorum queues: reintroduced Raft WAL max entries default of 500K. GitHub issue: #16382 A quorum queue could crash during recovery after an unclean shutdown PR: rabbitmq/ra#629 Stream queue argument validation was improved. GitHub issue: #16285 Enhancements channel_max was renamed to max_channels in rabbitmq.conf . The original name is still supported as an alias. GitHub issue: #16347 connection_max was renamed to max_connections in rabbitmq.conf . The original name is still supported as an alias. GitHub issue: #16347 The per-node max_connections limit is now enforced for AMQP 1.0 connections as well as AMQP 0-9-1 ones. GitHub issue: #16300 When a plain-text client connects to a TLS listener (or vice versa) for AMQP 0-9-1, MQTT, STOMP, and the Stream protocol, target node will log a more useful message. GitHub issues: #16342 , #16344 The permission cache is now traversed less often during AMQP 1.0 management and AMQP 0-9-1 channel checks. GitHub issue: #16274 Stream Plugin Bug Fixes Stream protocol: an open frame with empty properties is now handled correctly. GitHub issue: #16341 Enhancements It is now possible to cap the maximum number of concurrent Stream Protocol client connections using the stream.max_connections configuration key in rabbitmq.conf . GitHub issue: #16341 Management Plugin Bug Fixes HTTP API GET /api/connections could return a 500 response when STOMP connections were present. GitHub issue: #16435 Enhancements It is now possible to cap the maximum number of concurrent HTTP API connections using the management.tcp.max_connections , management.ssl.max_connections configuration keys in rabbitmq.conf . GitHub issue: #16407 The peer (client) certificate serial number is now exposed in the management UI and select CLI commands. GitHub issue: #16463 Prometheus Plugin Enhancements It is now possible to cap the maximum number of concurrent HTTP API connections using the prometheus.tcp.max_connections , prometheus.ssl.max_connections configuration keys in rabbitmq.conf . GitHub issue: #16407 MQTT Plugin Bug Fixes The MQTT connection process no longer fails and logs an exception when keepalive checks encounter socket errors on an already-closed connection. GitHub issue: #16391 Enhancements It is now possible to cap the maximum number of concurrent MQTT client connections using the mqtt.max_connections configuration key in rabbitmq.conf . GitHub issue: #16367 Federation Plugin Bug Fixes Federation links could fail to start during rolling cluster restarts. GitHub issues: #16234 , #16224 LDAP Plugin Enhancements New rabbitmq.conf configuration settings for TLS cipher suites: auth_ldap.ssl_options.ciphers.* . GitHub issue: #16226 HTTP Auth Backend Plugin Enhancements New rabbitmq.conf configuration settings for TLS cipher suites: auth_http.ssl_options.ciphers.* . GitHub issue: #16226 Auth Backend Cache Plugin Bug Fixes The cache was not effective for reconnecting clients. GitHub issues: #16255 , #16258 Trust Store Plugin Bug Fixes A user-provided fail_if_no_peer_cert value in the plugin's TLS options is now respected. Previously, an internal default could override the configured value. GitHub issue: #16201 Enhancements New rabbitmq.conf configuration settings for TLS cipher suites: trust_store.ssl_options.ciphers.* . GitHub issue: #16226 Dependency Changes ra was upgraded to 3.1.7 cuttlefish was upgraded to 3.7.0 cowboy was upgraded to 2.15.0 cowlib was upgraded to 2.16.1 gun was upgraded to 2.3.0

RabbitMQ 4.2.7 is a maintenance release in the 4.2.x release series . It is strongly recommended that you read 4.2.0 release notes in detail if upgrading from a version prior to 4.2.0 . Minimum Supported Erlang Version RabbitMQ and Erlang/OTP Compatibility Matrix has more details on Erlang version requirements for RabbitMQ. Nodes will fail to start on older Erlang releases. Changes Worth Mentioning Release notes can be found on GitHub at rabbitmq-server/release-notes . Core Server Bug Fixes A virtual host could be falsely considered to be deleted in certain metadata store error and timeout scenarios. GitHub issue: #16422 Passive queue and exchange declarations are now allowed for users that have any permission on the virtual host ( configure , write , or read ), not only configure . GitHub issue: #16272 Classic queue message store: garbage collection is now stopped cleanly during node shutdown. GitHub issue: #15498 Fixed a bug where quorum queue's at-least-once dead lettering could direct commands to the wrong member (replica). GitHub issue: #16203 Stream queue argument validation was improved. GitHub issue: #16285 Enhancements channel_max was renamed to max_channels in rabbitmq.conf . The original name is still supported as an alias. GitHub issue: #16347 connection_max was renamed to max_connections in rabbitmq.conf . The original name is still supported as an alias. GitHub issue: #16347 The per-node max_connections limit is now enforced for AMQP 1.0 connections as well as AMQP 0-9-1 ones. GitHub issue: #16300 The permission cache is now traversed less often during AMQP 1.0 management and AMQP 0-9-1 channel checks. GitHub issue: #16274 Stream Plugin Bug Fixes Stream protocol: an open frame with empty properties is now handled correctly. GitHub issue: #16341 Enhancements It is now possible to cap the maximum number of concurrent Stream Protocol client connections using the stream.max_connections configuration key in rabbitmq.conf . GitHub issue: #16341 Management Plugin Bug Fixes HTTP API GET /api/connections could return a 500 response when STOMP connections were present. GitHub issue: #16435 Enhancements It is now possible to cap the maximum number of concurrent HTTP API connections using the management.tcp.max_connections , management.ssl.max_connections configuration keys in rabbitmq.conf . GitHub issue: #16407 The peer (client) certificate serial number is now exposed in the management UI and select CLI commands. GitHub issue: #16463 Prometheus Plugin Enhancements It is now possible to cap the maximum number of concurrent HTTP API connections using the prometheus.tcp.max_connections , prometheus.ssl.max_connections configuration keys in rabbitmq.conf . GitHub issue: #16407 MQTT Plugin Bug Fixes The MQTT connection process no longer fails and logs an exception when keepalive checks encounter socket errors on an already-closed connection. GitHub issue: #16391 Enhancements It is now possible to cap the maximum number of concurrent MQTT client connections using the mqtt.max_connections configuration key in rabbitmq.conf . GitHub issue: #16367 Federation Plugin Bug Fixes Federation links could fail to start during rolling cluster restarts. GitHub issues: #16234 , #16224 LDAP Plugin Enhancements New rabbitmq.conf configuration settings for TLS cipher suites: auth_ldap.ssl_options.ciphers.* . GitHub issue: #16226 HTTP Auth Backend Plugin Enhancements New rabbitmq.conf configuration settings for TLS cipher suites: auth_http.ssl_options.ciphers.* . GitHub issue: #16226 Auth Backend Cache Plugin Bug Fixes The cache was not effective for reconnecting clients. GitHub issues: #16255 , #16258 Trust Store Plugin Bug Fixes A user-provided fail_if_no_peer_cert value in the plugin's TLS options is now respected. Previously, an internal default could override the configured value. GitHub issue: #16201 Enhancements New rabbitmq.conf configuration settings for TLS cipher suites: trust_store.ssl_options.ciphers.* . GitHub issue: #16226 Dependency Changes ra was upgraded to 2.17.3 cuttlefish was upgraded to 3.7.0 cowboy was upgraded to 2.15.0 cowlib was upgraded to 2.16.1 gun was upgraded to 2.3.0

RabbitMQ 4.3.0 is a new feature release. Breaking Changes and Compatibility Notes Mnesia and Parition Handling Strategies are Removed Since only 4.2.x clusters can upgrade to 4.3.0 in place , this won't be a breaking change for nearly all instalations but it will affect community plugins that use Mnesia. All partition handling-related keys in rabbitmq.conf will be accepted by 4.3.0 nodes but won't have any effect: cluster_partition_handling cluster_partition_handling.pause_if_all_down.recover cluster_partition_handling.pause_if_all_down.nodes.$name Team RabbitMQ recommends removing the above keys from rabbitmq.conf before or shortly after upgrading. Deprecated Features are Now Disabled by Default A number of deprecated features are now disabled by default and require the user to opt-in in order to use them. This includes non-durable (transient) non-exclusive queues: attempts to declare a queue with such property combination will be rejected by default. Use durable queues, transient exclusive queues, or durable queues with a queue TTL instead. To explicitly allow transient non-exclusive queues, make sure that all nodes in the cluster include the following rabbitmq.conf key and were restarted so that all nodes have a consistent view of the deprecated feature settings: # Enables deprecated non-durable (transient) non-exclusive queues # (disabled by default as of RabbitMQ `4.3.0`, will be removed in a later version). # # Must be effective on all cluster nodes BEFORE # the cluster is upgraded to `4.3.0`. # If only some nodes have the setting configured, it will not have the desired effect. deprecated_features.permit.transient_nonexcl_queues = true If only some nodes have setting configured, it will not have the desired effect. Classic Queues v1 Storage (CQv1) is Removed This release removes the original classic queue storage implementation these days known as CQv1. A 2nd generation implementation called CQv2 has been adopted as the default starting with 4.2.0 . This means that attempts to declare a queue using the following optional queue arguments will fail: x-queue-mode set to any value x-queue-version set to 1 Existing classic queues upgraded to CQv2 during an earlier upgrade to 4.2.x will continue operating as usual. Consumer Timeouts are No Longer Evaluated for Classic Queues and Streams This release moves consumer timeout handling responsibility into the queues themselves. Also, all protocols (except for the stream protocol) now evaluate consumer timeout for queue types that support them. Classic queues and streams never evaluate consumer timeouts as their use cases largely avoid the need for such as feature. Release Highlights Khepri is Now The Only Metadata Store As of this release, Khepri is the only metadata store supported by RabbitMQ: Mnesia was removed completely. In practical operational terms, this means that For a cluster to be available, a majority of nodes must be online at all times Failure and partition recovery in a RabbitMQ cluster is now significantly simpler and uniform: all components that have replicated state (Khepri, quorum queues, streams) recover per Raft recovery semantics Quorum Queues Enhancements This release upgrades the Ra dependency to 3.x and introduces a new (8th) version of the quorum queue state machine with several new features and optimisations: Strict priority queues with per-priority message counts, correct redelivery ordering, and priority-aware message expiration Delayed retry for quorum queues: configurable increasing backoff when messages are returned Consumer timeout for quorum queues: configurable timeout for unacknowledged messages, with protocol-specific handling for AMQP 1.0 and MQTT Recovery snapshots and snapshot throttling to reduce recovery time and improve snapshotting decisions Memory optimisations including compact message references, optimised tuple storage for delayed keys, and removal of rabbit_fifo_index usage Upgrading to 4.3.0 Documentation Guides on Upgrades See the Upgrading guide for documentation on upgrades and GitHub releases for release notes of individual releases. This release series supports upgrades from 4.2.x . Upgrades from earlier series are not supported: users must upgrade to the latest available 4.2.x patch release before upgrading to 4.3.0 . New Required Feature Flags All feature flags introduced in 4.2.0 and earlier are required, including the following: rabbitmq_4.2.0 rabbitmq_4.1.0 rabbitmq_4.0.0 khepri_db quorum_queue_non_voters message_containers_deaths_v2 Enable all required feature flags before upgrading to 4.3.0 . If your RabbitMQ cluster had plugin rabbitmq_amqp1_0 enabled in RabbitMQ 3.13.x (and your cluster still serves AMQP 1.0 client connections in 4.x ), your cluster should do at least one rolling update after enabling feature flag rabbitmq_4.0.0 but before upgrading to 4.3.0 . Deprecated Features In 4.3.0 the deprecation phase of the following features advanced from permitted_by_default to denied_by_default : amqp_address_v1 amqp_filter_set_bug global_qos queue_master_locator transient_nonexcl_queues And the deprecated feature ram_node_type has been removed. Mixed Version Cluster Compatibility RabbitMQ 4.3.0 nodes can run alongside 4.2.x in the same cluster. Mixed version clusters are a mechanism that allows rolling upgrades and are not meant to be run for extended periods of time (no more than a few hours). Recommended Post-upgrade Procedures This version does not require any additional post-upgrade procedures compared to other versions. Changes Worth Mentioning Core Server Enhancements When a message is rejected by a queue, RabbitMQ now provides the queue name and rejection reason to AMQP 1.0 publishers in the Rejected outcome. This is particularly useful when multiple queues are bound to an exchange, as it allows publishers to identify which specific queue out of several target queues rejected the message and why (e.g., maximum queue length reached or queue unavailable). Previously, publishers had no way to determine which queue rejected their message or the reason for rejection. The queue name and reason are included in the info field of the Rejected outcome's error field: queue: <queue name> reason: maxlen | unavailable GitHub issue: #15075 Quorum queues now support strict priority queues with per-priority message counts, correct redelivery ordering across priorities, and priority-aware message expiration scans. GitHub issue: #13885 Quorum queues now support delayed retry with configurable backoff based on delivery count. When messages are returned (via reject, nack, or modify), they can be held in a delayed state before becoming available again. The delay is based on delivery count: min(min_delay * delivery_count, max_delay) . Configuration is available via queue arguments ( x-delayed-retry-type , x-delayed-retry-min , x-delayed-retry-max ) or policy keys ( delayed-retry-type , delayed-retry-min , delayed-retry-max ). The retry type can be set to disabled , all , failed , or returned . GitHub issue: #13885 Quorum queues now support a configurable consumer timeout . When a consumer holds unacknowledged messages beyond the timeout, the messages are returned to the queue. For AMQP 1.0 clients, timed-out deliveries are released via DISPOSITION(state=released) instead of detaching the link, allowing the consumer to recover without re-attaching. MQTT consumers are also supported. The timeout can be set via the x-consumer-timeout consumer argument, queue argument, consumer-timeout policy key, or the global consumer_timeout setting in rabbitmq.conf . GitHub issue: #13885 A new consumer_disconnected_timeout setting controls how long quorum queues wait before returning messages when a consumer's node becomes unreachable due to a network partition. The default is 60 seconds. Configurable via consumer_disconnected_timeout in rabbitmq.conf , the consumer-disconnected-timeout policy key, or the x-consumer-disconnected-timeout queue argument. GitHub issue: #13885 Quorum queue recovery snapshots reduce recovery time after a member restart by avoiding the need to replay all enqueue commands from the log. GitHub issue: #13885 Quorum queue snapshot throttling now uses WAL fill ratio and reclaimable byte tracking to make smarter snapshotting decisions, yielding roughly one snapshot per queue per WAL cycle instead of excessive snapshots in shallow, fast-flowing queues. GitHub issue: #13885 Quorum queue memory optimisations : message references now use a compact packed integer representation ("compact" means up to 59-bit) when possible, halving per-message memory overhead in many scenarios. The rabbit_fifo_index module is no longer used by the main state machine. GitHub issue: #13885 Quorum queues now allow unlimited explicit message returns. The delivery limit is based on delivery-count rather than acquired-count , so messages can be explicitly returned to the queue without counting towards the delivery limit. GitHub issue: #13885 The x-modulus-hash exchange type, previously provided by the sharding plugin, was moved into the core and reworked to provide stable message routing (distribution) assuming a stable set of bindings, including between node restarts. GitHub issue: #15849 When quorum queue members (replicas) are deleted from a node, either manually via rabbitmq-queues shrink or as part of rabbitmqctl forget_cluster_node , the members are stopped in parallel. GitHub issue: #15081 Purging a quorum queue now also removes at-least-once dead-lettered messages that were pending delivery. GitHub issue: #13885 AMQP 0-9-1: when a connection's credentials are refreshed, the permissions cache is now cleared and consumer permissions are re-validated immediately GitHub issue: #16092 Quorum queue delivery limit can now be changed via policy without queue redeclaration GitHub issue: #16035 Khepri topic exchange routing projection (v4): replaced the internal representation with a trie backed by an ordered_set ETS table, significantly improving routing performance for topic exchanges with many bindings GitHub issue: #15619 Quorum queues notify AMQP 1.0 clients of Single Active Consumer state changes GitHub issue: #15736 More rabbitmq.conf keys now accept tagged values (e.g., encrypted:... ) GitHub issue: #15808 Startup banner no longer includes the Erlang cookie hash GitHub issue: #16087 Optimised AMQP 1.0 message container annotation handling during modify outcomes GitHub issue: #15743 Bulk queue delete with Khepri has been optimized GitHub issue: #14902 Optimised quorum queue message expiry scanning GitHub issue: #15846 AMQP 0-9-1: configure permission checks now apply to passive queue and exchange declarations, matching the behavior of their regular counterparts GitHub issue: #16085 Khepri snapshot interval is now configurable in rabbitmq.conf GitHub issue: #16011 Quorum queue Raft settings: additional configuration settings are now exposed in rabbitmq.conf , including maximum segment size GitHub issue: #15962 Bug Fixes If a quorum queue with a large backlog terminated abnormally, node memory footprint could spike. GitHub issue: #15837 rabbitmqctl forget_cluster_node now removes all quorum queue and stream members (replicas) before proceeding to leave the metadata store cluster. This order minimizes the risk of some replicas being left behind on the leaving node. GitHub issue: #15729 Quorum queue at-most-once dead lettering for the overflow behaviour drop-head now happens in the correct order. GitHub issue: #14926 Feature flag state in the registry and on disk were not consistent for a period of time during node boot. GitHub issue: #14943 Classic queues now implement AMQP 1.0 delivery-count and first-acquirer headers properly. GitHub issue: #15020 Quorum queues returned an incorrect consumer count in the response to a passive queue.declare operation GitHub issue: #16185 Classic queue shared store could leave stale index entries after segment removal or rollover, causing unnecessary disk space usage GitHub issue: #16142 Bindings targeting Direct Reply-to pseudo-queues are now rejected instead of being silently accepted without any functional effect GitHub issue: #15935 AMQP 1.0 sessions could grant too many credits in certain failure and recovery scenarios GitHub issue: #15883 Quorum queues: acquired-count is now correctly preserved when dead-lettering GitHub issue: #16039 AMQP 1.0: attaching with a link handle already in use on the same session is now rejected with a handle-in-use session error, as required by the specification GitHub issue: #16039 Quorum queues: Single Active Consumer could incorrectly report multiple active consumers in certain timing scenarios GitHub issue: #15733 Quorum queues: consumer timeout could fail to trigger under certain conditions GitHub issue: #15805 The channel limit exceeded error message now correctly identifies the per-user limit as the source of the constraint GitHub issue: #15750 Stream Plugin Bug Fixes stream.read_ahead is a new setting that controls how much data is prefetched from disk for stream reads (consumption). GitHub issue: #14948 Stream deletion is now more resilient and can handle certain mid-deletion failure scenarios. GitHub issue: #14852 new_stream coordinator command is now idempotent. Previously, concurrent or retried stream declarations could produce spurious errors even though the stream was created successfully GitHub issue: #15706 Prometheus Plugin Enhancements /metrics/detailed endpoint now supports filtering queue metrics by queue name GitHub issue: #15689 Grafana Dashboards Enhancements The dashboards were updated for the most recent RabbitMQ release series. Replaced explicit rate intervals with $__rate_interval for better compatibility across different scrape intervals GitHub issue: #15978 Management Plugin Enhancements GET /api/queues/{vhost} requests no longer perform unnecessary virtual host permission checks and log less (at debug level) as a result. GitHub issue: #14923 Quorum queue delayed retry configuration and status, per-priority message counts, and consumer timeout state are now displayed in the management UI. GitHub issue: #13885 GET /users/{user}/queues has been added. GitHub issue: #15074 HTTP API displays static connection info (peer address, TLS details, auth mechanism) even when stats collection is disabled via rabbitmq.conf GitHub issue: #16009 Bug Fixes effective_policy_definition in HTTP API responses now returns an empty JSON object (not an array or empty string) when no policy applies to a queue GitHub issue: #16017 Management UI: OAuth 2 used side by side with Basic Auth could fail to reload provider configuration correctly GitHub issue: #15793 Management UI: preference cookie expiry now respects the configured session timeout setting rather than using a hardcoded value GitHub issue: #15814 Management UI: users were presented with a 401 error after changing their own password via the UI. The session is now refreshed automatically GitHub issue: #15730 The deprecated, unused GET /api/auth endpoint was removed. It has been out of use since 3.11 but never removed. GitHub issue: #16083 POST /api/users/bulk-delete now respects the protected_users configuration, matching the behavior of the single-user DELETE /api/users/:name endpoint GitHub issue: #16143 MQTT Plugin Enhancements For MQTT 5.0 publishers, when a message is rejected because the target queue's maximum length is exceeded, RabbitMQ now returns a Quota exceeded reason code in the PUBACK packet. This provides publishers with actionable information about why their message was rejected. GitHub issue: #15075 MQTT QoS 0 queue type now reports member information in management API responses GitHub issue: #15656 Web MQTT Plugin Enhancements A default max_frame_size is now set on WebSocket connections, bounding decompressed frame sizes. The limit starts at mqtt.max_packet_size_unauthenticated and is raised after successful CONNECT GitHub issue: #16180 A login_timeout is now enforced for WebSocket connections, matching the TCP listener behavior GitHub issue: #16120 WebSocket Origin header will be validated web_mqtt.allow_origins GitHub issue: #16158 STOMP Plugin Enhancements For certain destinations that previously used non-durable (transient) queues, STOMP subscriptions now use exclusive queues, as non-exclusive transient queues are a deprecated property combination disabled by default as of this release GitHub issue: #13016 Web STOMP Plugin Enhancements WebSocket Origin header validation is now available via web_stomp.allow_origins GitHub issue: #16158 Federation Plugin Enhancements Federation links and their connections are now stopped in parallel. This significantly improves shutdown time for nodes with many (into thousands) federation links. GitHub issue: #15271 Federation links no longer restart during plugin or node shutdown. For nodes with hundreds or thousands of federation links, link recovery could significantly delay node shutdown. GitHub issue: #15258 Federation Management Plugin Bug Fixes Federation link restart operations now require the policymaker tag GitHub issue: #16051 Shovel Plugin Enhancements An optional src-consumer-name property can be specified to define the consumer tag ( amqp091 and local src-protocol ) or link identifier ( amqp10 protocol) Bug Fixes Improved target node resource alarm handling for AMQP 1.0 and local shovels. GitHub issue: #14886 Local shovels could run into an exception that would cause a shovel restart. GitHub issue: #14872 AMQP 1.0 shovels ignored the sasl URI parameter. GitHub issue: #14867 Shovel Management Plugin Bug Fixes Shovel management: DELETE operations now require the policymaker tag, matching the federation plugin counterpart GitHub issue: #16051 OAuth 2 Plugin Bug Fixes A usability improvement allows the plugin to automatically load the trusted system x.509 (TLS) certificates. GitHub issue: #14927 The auth cache backend now correctly delegates token expiry timestamps to the wrapped backend, ensuring connections are closed when tokens expire GitHub issue: #16100 LDAP Plugin Enhancements LDAP queries, including multi-line ones, can now be specified in rabbitmq.conf . GitHub issue: #14868 Bug Fixes A usability improvement allows the plugin to automatically load the trusted system certificates when the user only enables TLS for the LDAP client but does not configure any other settings. GitHub issue: #14937 DN values are now handled per RFC 4514 GitHub issue: #16101 HTTP Auth Backend Plugin Enhancements The HTTP Auth Backend can now optionally provide a custom authorization denial reason to AMQP clients. To opt in, return deny <Reason> (instead of only deny ) in the HTTP response body of your HTTP auth backend and set the following in your rabbitmq.conf file: auth_http.authorization_failure_disclosure = true See the README for more information. GitHub issue: #14641 Sharding Plugin Enhancements The x-modulus-hash exchange type, previously provided by the sharding plugin, was moved into the core and reworked to provide stable message routing (distribution) assuming a stable set of bindings, including between node restarts. GitHub issue: #15849 Trust Store Plugin Enhancements Refactored certificate identification to avoid (unlikely) conflicts GitHub issue: #16116 The plugin now provides CLI commands for trust store certificate management have been introduced GitHub issue: #15746 Rejected certificates are now logged with additional diagnostic details GitHub issue: #15889 Tracing Plugin Bug Fixes Trace file downloads now set the charset to UTF-8 when serving trace files. GitHub issue: #13952 Dependency Changes ra was upgraded to 3.1.6 khepri was upgraded to 0.18.0 osiris was upgraded to 1.3.1 gen_batch_server was upgraded to 0.9.2 cuttlefish was upgraded to 3.6.0 Source Code Archives To obtain source code of the entire distribution, please download the archive named rabbitmq-server-4.3.0.tar.xz instead of the source tarball produced by GitHub.

RabbitMQ 4.2.6 is a maintenance release in the 4.2.x release series . It is strongly recommended that you read 4.2.0 release notes in detail if upgrading from a version prior to 4.2.0 . Minimum Supported Erlang Version RabbitMQ and Erlang/OTP Compatibility Matrix has more details on Erlang version requirements for RabbitMQ. Nodes will fail to start on older Erlang releases. Changes Worth Mentioning Release notes can be found on GitHub at rabbitmq-server/release-notes . Core Server Bug Fixes Quorum queues: get_checked_out aux command could return messages in incorrect order GitHub issue: #16008 rabbitmqctl forget_cluster_node now removes all quorum queue and stream members (replicas) before proceeding to leave the metadata store cluster. This order minimizes the risk of some replicas being left behind on the leaving node. GitHub issue: #15729 The channel limit exceeded error message now correctly identifies the per-user limit as the reason GitHub issue: #15750 AMQP 0-9-1: configure permission checks now apply to passive queue and exchange declarations, matching the behavior of their regular counterparts Khepri: missing keys are now correctly distinguished from errors in certain internal operations, avoiding spurious error-level log messages GitHub issue: #15942 Bindings targeting Direct Reply-to pseudo-queues are now rejected instead of being silently accepted without any functional effect GitHub issue: #15935 Enhancements More rabbitmq.conf keys now accept tagged values (e.g., encrypted:... ) GitHub issue: #15808 When quorum queue members (replicas) are deleted from a node, either manually via rabbitmq-queues shrink or as part of rabbitmqctl forget_cluster_node , the members are stopped in parallel GitHub issue: #15081 AMQP 0-9-1: configure permission checks now apply to passive queue and exchange declarations, matching the behavior of their regular counterparts GitHub issue: #16085 AMQP 0-9-1: when a connection's credentials are refreshed, the permissions cache is now cleared and consumer permissions are re-validated immediately GitHub issue: #16092 Management Plugin Bug Fixes effective_policy_definition in HTTP API responses now returns an empty JSON object (not an array or empty string) when no policy applies to a queue GitHub issue: #16017 Management UI: OAuth 2 combined with basic_auth could fail to reload provider configuration correctly GitHub issue: #15858 Management UI: preference cookie expiry now respects the configured session timeout setting rather than using a hardcoded value GitHub issue: #15814 Management UI: users were presented with a 401 error after changing their own password via the UI. The session is now refreshed automatically GitHub issue: #15730 The deprecated, unused GET /api/auth endpoint was removed It has been out of use since 3.11 but never removed. GitHub issue: #16083 POST /api/users/bulk-delete now respects the protected_users configuration, matching the behavior of the single-user DELETE /api/users/:name endpoint GitHub issue: #16143 Quorum queue status and stream tracking endpoints now enforce virtual host access checks, consistent with all other vhost-scoped endpoints GitHub issue: #16104 Enhancements HTTP API displays static connection info (peer address, TLS details, auth mechanism) even when stats collection is disabled via rabbitmq.conf GitHub issue: #16009 Super stream creation via HTTP API now verifies configure permission, matching the stream protocol code path GitHub issue: #16099 Management API regex filters ( ?name=...&use_regex=true ) now enforce match limits, preventing pathological patterns from consuming excessive CPU time GitHub issue: #16074 MQTT Plugin Bug Fixes Fixed a timing-sensitive issue around Last Will message delivery and session expiration GitHub issue: #15999 Enhancements MQTT QoS 0 queue type now reports member information in management API responses GitHub issue: #15656 Web MQTT Plugin Enhancements A default max_frame_size is now set on WebSocket connections, bounding decompressed frame sizes. The limit starts at mqtt.max_packet_size_unauthenticated and is raised after successful CONNECT GitHub issue: #16180 A login_timeout is now enforced for WebSocket connections, matching the TCP listener behavior GitHub issue: #16120 WebSocket Origin header validation is now available via web_mqtt.allow_origins GitHub issue: #16158 Web STOMP Plugin Enhancements A default max_frame_size is now set on WebSocket connections. A smaller pre-authentication limit is raised after successful STOMP CONNECT, matching the Web MQTT pattern GitHub issue: #16180 A login_timeout is now enforced for WebSocket connections, matching the TCP listener behavior GitHub issue: #16120 WebSocket Origin header validation is now available via web_stomp.allow_origins GitHub issue: #16158 Shovel Plugin Bug Fixes AMQP 1.0 shovels now properly detach links when closing connections, preventing spurious error log entries during shutdown GitHub issue: #15603 AMQP 1.0 shovel status no longer includes full connection URIs in API responses and CLI output GitHub issue: #16108 Shovel Management Plugin Bug Fixes DELETE operations now require the policymaker tag, matching the federation plugin counterpart GitHub issue: #16051 Federation Management Plugin Bug Fixes Federation link restart operations now require the policymaker tag GitHub issue: #16051 OAuth 2 Plugin Bug Fixes The auth cache backend now correctly delegates token expiry timestamps to the wrapped backend, ensuring connections are closed when tokens expire GitHub issue: #16100 OAuth 2 management UI: improved provider configuration loading and rendering GitHub issue: #15858 LDAP Plugin Bug Fixes DN values are now handled per RFC 4514 GitHub issue: #16101 Trust Store Plugin Enhancements Refactored certificate identification to avoid (unlikely) conflicts GitHub issue: #16116 Proper CLI commands for trust store certificate management have been introduced GitHub issue: #15746 Rejected certificates are now logged with additional diagnostic details GitHub issue: #15889 Consistent Hashing Exchange Plugin Bug Fixes Binding weights above 10,000 are now rejected. Previously, extremely large weights could cause excessive memory allocation GitHub issue: #16118 Dependency Changes khepri was upgraded to 0.17.7 gen_batch_server was upgraded to 0.9.1