current.rst

1.21.0 (Pending)

Incompatible Behavior Changes

Changes that are expected to cause an incompatibility if applicable; deployment changes are likely required

• xds: * became a reserved name for a wildcard resource that can be subscribed to and unsubscribed from at any time. This is a requirement for implementing the on-demand xDSes (like on-demand CDS) that can subscribe to specific resources next to their wildcard subscription. If such xDS is subscribed to both wildcard resource and to other specific resource, then in stream reconnection scenario, the xDS will not send an empty initial request, but a request containing * for wildcard subscription and the rest of the resources the xDS is subscribed to. If the xDS is only subscribed to wildcard resource, it will try to send a legacy wildcard request. This behavior implements the recent changes in :ref:`xDS protocol <xds_protocol>` and can be temporarily reverted by setting the envoy.restart_features.explicit_wildcard_resource runtime guard to false.

Minor Behavior Changes

Changes that may cause incompatibilities for some users, but should not for most

• bandwidth_limit: added :ref:`response trailers <envoy_v3_api_field_extensions.filters.http.bandwidth_limit.v3.BandwidthLimit.enable_response_trailers>` when request or response delay are enforced.
• bandwidth_limit: added :ref:`bandwidth limit stats <config_http_filters_bandwidth_limit>` request_enforced and response_enforced.
• config: the log message for "gRPC config stream closed" now uses the most recent error message, and reports seconds instead of milliseconds for how long the most recent status has been received.
• dns: now respecting the returned DNS TTL for resolved hosts, rather than always relying on the hard-coded :ref:`dns_refresh_rate. <envoy_v3_api_field_config.cluster.v3.Cluster.dns_refresh_rate>` This behavior can be temporarily reverted by setting the runtime guard envoy.reloadable_features.use_dns_ttl to false.
• http: usage of the experimental matching API is no longer guarded behind a feature flag, as the corresponding protobuf fields have been marked as WIP.
• json: switching from rapidjson to nlohmann/json. This behavioral change can be temporarily reverted by setting runtime guard envoy.reloadable_features.remove_legacy_json to false.
• listener: destroy per network filter chain stats when a network filter chain is removed during the listener in place update.
• quic: add back the support for IETF draft 29 which is guarded via envoy.reloadable_features.FLAGS_quic_reloadable_flag_quic_disable_version_draft_29. It is off by default so Envoy only supports RFCv1 without flipping this runtime guard explicitly. Draft 29 is not recommended for use.

Bug Fixes

Changes expected to improve the state of the world and are unlikely to have negative effects

• ext_authz: fix the ext_authz network filter to correctly set response flag and code details to UAEX when a connection is denied.
• listener: fixed the crash when updating listeners that do not bind to port.
• thrift_proxy: fix the thrift_proxy connection manager to correctly report success/error response metrics when performing :ref:`payload passthrough <envoy_v3_api_field_extensions.filters.network.thrift_proxy.v3.ThriftProxy.payload_passthrough>`.

Removed Config or Runtime

Normally occurs at the end of the :ref:`deprecation period <deprecated>`

• compression: removed envoy.reloadable_features.enable_compression_without_content_length_header runtime guard and legacy code paths.
• grpc-web: removed envoy.reloadable_features.grpc_web_fix_non_proto_encoded_response_handling and legacy code paths.
• health check: removed envoy.reloadable_features.health_check.immediate_failure_exclude_from_cluster runtime guard and legacy code paths.
• http: removed envoy.reloadable_features.add_and_validate_scheme_header and legacy code paths.
• http: removed envoy.reloadable_features.check_unsupported_typed_per_filter_config, Envoy will always check unsupported typed per filter config if the filter isn't optional.
• http: removed envoy.reloadable_features.dont_add_content_length_for_bodiless_requests deprecation and legacy code paths.
• http: removed envoy.reloadable_features.grpc_json_transcoder_adhere_to_buffer_limits and legacy code paths.
• http: removed envoy.reloadable_features.http2_skip_encoding_empty_trailers and legacy code paths. Envoy will always encode empty trailers by sending empty data with end_stream true (instead of sending empty trailers) for HTTP/2.
• http: removed envoy.reloadable_features.improved_stream_limit_handling and legacy code paths.
• http: removed envoy.reloadable_features.remove_forked_chromium_url and legacy code paths.
• http: removed envoy.reloadable_features.return_502_for_upstream_protocol_errors. Envoy will always return 502 code upon encountering upstream protocol error.
• http: removed envoy.reloadable_features.treat_host_like_authority and legacy code paths.
• http: removed envoy.reloadable_features.treat_upstream_connect_timeout_as_connect_failure and legacy code paths.
• upstream: removed envoy.reloadable_features.upstream_host_weight_change_causes_rebuild and legacy code paths.

New Features

• access log: added :ref:`grpc_stream_retry_policy <envoy_v3_api_field_extensions.access_loggers.grpc.v3.CommonGrpcAccessLogConfig.grpc_stream_retry_policy>` to the gRPC logger to reconnect when a connection fails to be established.
• api: added support for xds.type.v3.TypedStruct in addition to the now-deprecated udpa.type.v1.TypedStruct proto message, which is a wrapper proto used to encode typed JSON data in a google.protobuf.Any field.
• bootstrap: added :ref:`typed_dns_resolver_config <envoy_v3_api_field_config.bootstrap.v3.Bootstrap.typed_dns_resolver_config>` in the bootstrap to support DNS resolver as an extension.
• cluster: added :ref:`typed_dns_resolver_config <envoy_v3_api_field_config.cluster.v3.Cluster.typed_dns_resolver_config>` in the cluster to support DNS resolver as an extension.
• config: added :ref:`environment_variable <envoy_v3_api_field_config.core.v3.datasource.environment_variable>` to the :ref:`DataSource <envoy_v3_api_msg_config.core.v3.datasource>`.
• dns: added :ref:`ALL <envoy_v3_api_enum_value_config.cluster.v3.Cluster.DnsLookupFamily.ALL>` option to return both IPv4 and IPv6 addresses.
• dns_cache: added :ref:`typed_dns_resolver_config <envoy_v3_api_field_extensions.common.dynamic_forward_proxy.v3.DnsCacheConfig.typed_dns_resolver_config>` in the dns_cache to support DNS resolver as an extension.
• dns_filter: added :ref:`typed_dns_resolver_config <envoy_v3_api_field_extensions.filters.udp.dns_filter.v3.DnsFilterConfig.ClientContextConfig.typed_dns_resolver_config>` in the dns_filter to support DNS resolver as an extension.
• dns_resolver: added :ref:`CaresDnsResolverConfig<envoy_v3_api_msg_extensions.network.dns_resolver.cares.v3.CaresDnsResolverConfig>` to support c-ares DNS resolver as an extension.
• dns_resolver: added :ref:`AppleDnsResolverConfig<envoy_v3_api_msg_extensions.network.dns_resolver.apple.v3.AppleDnsResolverConfig>` to support apple DNS resolver as an extension.
• ext_authz: added :ref:`query_parameters_to_set <envoy_v3_api_field_service.auth.v3.OkHttpResponse.query_parameters_to_set>` and :ref:`query_parameters_to_remove <envoy_v3_api_field_service.auth.v3.OkHttpResponse.query_parameters_to_remove>` for adding and removing query string parameters when using a gRPC authorization server.
• http: added support for :ref:`retriable health check status codes <envoy_v3_api_field_config.core.v3.HealthCheck.HttpHealthCheck.retriable_statuses>`.
• listener: added API for extensions to access :ref:`typed_filter_metadata <envoy_v3_api_field_config.core.v3.Metadata.typed_filter_metadata>` configured in the listener's :ref:`metadata <envoy_v3_api_field_config.listener.v3.Listener.metadata>` field.
• listener: added support for :ref:`MPTCP <envoy_v3_api_field_config.listener.v3.Listener.enable_mptcp>` (multipath TCP).
• oauth filter: added :ref:`cookie_names <envoy_v3_api_field_extensions.filters.http.oauth2.v3.OAuth2Credentials.cookie_names>` to allow overriding (default) cookie names (BearerToken, OauthHMAC, and OauthExpires) set by the filter.
• oauth filter: setting IdToken and RefreshToken cookies if they are provided by Identity provider along with AccessToken.
• tcp: added a :ref:`FilterState <envoy_v3_api_msg_type.v3.HashPolicy.FilterState>` :ref:`hash policy <envoy_v3_api_msg_type.v3.HashPolicy>`, used by :ref:`TCP proxy <envoy_v3_api_field_extensions.filters.network.tcp_proxy.v3.TcpProxy.hash_policy>` to allow hashing load balancer algorithms to hash on objects in filter state.
• tcp_proxy: added support to populate upstream http connect header values from stream info.
• thrift_proxy: add header to metadata filter for turning headers into dynamic metadata.
• thrift_proxy: add upstream response zone metrics in the form cluster.cluster_name.zone.local_zone.upstream_zone.thrift.upstream_resp_success.
• thrift_proxy: add upstream metrics to show decoding errors and whether exception is from local or remote, e.g. cluster.cluster_name.thrift.upstream_resp_exception_remote.
• thrift_proxy: add host level success/error metrics where success is a reply of type success and error is any other response to a call.
• thrift_proxy: support header flags.
• thrift_proxy: support subset lb when using request or route metadata.
• tls: added support for only verifying the leaf CRL in the certificate chain with :ref:`only_verify_leaf_cert_crl <envoy_v3_api_field_extensions.transport_sockets.tls.v3.CertificateValidationContext.only_verify_leaf_cert_crl>`.
• transport_socket: added :ref:`envoy.transport_sockets.tcp_stats <envoy_v3_api_msg_extensions.transport_sockets.tcp_stats.v3.Config>` which generates additional statistics gathered from the OS TCP stack.
• udp: add support for multiple listener filters.
• upstream: added the ability to :ref:`configure max connection duration <envoy_v3_api_field_config.core.v3.HttpProtocolOptions.max_connection_duration>` for upstream clusters.
• vcl_socket_interface: added VCL socket interface extension for fd.io VPP integration to :ref:`contrib images <install_contrib>`. This can be enabled via :ref:`VCL <envoy_v3_api_msg_extensions.vcl.v3alpha.VclSocketInterface>` configuration.
• xds: re-introduced unified delta and sotw xDS multiplexers that share most of the implementation. Added a new runtime config envoy.reloadable_features.unified_mux (disabled by default) that when enabled, switches xDS to use unified multiplexers.

Deprecated

• bootstrap: :ref:`dns_resolution_config <envoy_v3_api_field_config.bootstrap.v3.Bootstrap.dns_resolution_config>` is deprecated in favor of :ref:`typed_dns_resolver_config <envoy_v3_api_field_config.bootstrap.v3.Bootstrap.typed_dns_resolver_config>`.
• cluster: :ref:`dns_resolution_config <envoy_v3_api_field_config.cluster.v3.Cluster.dns_resolution_config>` is deprecated in favor of :ref:`typed_dns_resolver_config <envoy_v3_api_field_config.cluster.v3.Cluster.typed_dns_resolver_config>`.
• dns_cache: :ref:`dns_resolution_config <envoy_v3_api_field_extensions.common.dynamic_forward_proxy.v3.DnsCacheConfig.dns_resolution_config>` is deprecated in favor of :ref:`typed_dns_resolver_config <envoy_v3_api_field_extensions.common.dynamic_forward_proxy.v3.DnsCacheConfig.typed_dns_resolver_config>`.
• dns_filter: :ref:`dns_resolution_config <envoy_v3_api_field_extensions.filters.udp.dns_filter.v3.DnsFilterConfig.ClientContextConfig.dns_resolution_config>` is deprecated in favor of :ref:`typed_dns_resolver_config <envoy_v3_api_field_extensions.filters.udp.dns_filter.v3.DnsFilterConfig.ClientContextConfig.typed_dns_resolver_config>`.