current.rst

1.19.0 (Pending)

Incompatible Behavior Changes

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

• grpc_bridge_filter: the filter no longer collects grpc stats in favor of the existing grpc stats filter. The behavior can be reverted by changing runtime key envoy.reloadable_features.grpc_bridge_stats_disabled.
• tracing: update Apache SkyWalking tracer version to be compatible with 8.4.0 data collect protocol. This change will introduce incompatibility with SkyWalking 8.3.0.

Minor Behavior Changes

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

• access_log: add new access_log command operator %REQUEST_TX_DURATION%.
• access_log: remove extra quotes on metadata string values. This behavior can be temporarily reverted by setting envoy.reloadable_features.unquote_log_string_values to false.
• admission control: added :ref:`admission control <envoy_v3_api_field_extensions.filters.http.admission_control.v3alpha.AdmissionControl.max_rejection_probability>` whose default value is 80%, which means that the upper limit of the default rejection probability of the filter is changed from 100% to 80%.
• aws_request_signing: requests are now buffered by default to compute signatures which include the payload hash, making the filter compatible with most AWS services. Previously, requests were never buffered, which only produced correct signatures for requests without a body, or for requests to S3, ES or Glacier, which used the literal string UNSIGNED-PAYLOAD. Buffering can be now be disabled in favor of using unsigned payloads with compatible services via the new use_unsigned_payload filter option (default false).
• cluster: added default value of 5 seconds for :ref:`connect_timeout <envoy_v3_api_field_config.cluster.v3.Cluster.connect_timeout>`.
• dns: changed apple resolver implementation to not reuse the UDS to the local DNS daemon.
• dns cache: the new :ref:`dns_query_timeout <envoy_v3_api_field_extensions.common.dynamic_forward_proxy.v3.DnsCacheConfig.dns_query_timeout>` option has a default of 5s. See below for more information.
• http: disable the integration between :ref:`ExtensionWithMatcher <envoy_v3_api_msg_extensions.common.matching.v3.ExtensionWithMatcher>` and HTTP filters by default to reflects its experimental status. This feature can be enabled by seting envoy.reloadable_features.experimental_matching_api to true.
• http: replaced setting envoy.reloadable_features.strict_1xx_and_204_response_headers with settings envoy.reloadable_features.require_strict_1xx_and_204_response_headers (require upstream 1xx or 204 responses to not have Transfer-Encoding or non-zero Content-Length headers) and envoy.reloadable_features.send_strict_1xx_and_204_response_headers (do not send 1xx or 204 responses with these headers). Both are true by default.
• http: serve HEAD requests from cache.
• http: stop sending the transfer-encoding header for 304. This behavior can be temporarily reverted by setting envoy.reloadable_features.no_chunked_encoding_header_for_304 to false.
• http: the behavior of the present_match in route header matcher changed. The value of present_match is ignored in the past. The new behavior is present_match performed when value is true. absent match performed when the value is false. Please reference :ref:`present_match <envoy_v3_api_field_config.route.v3.HeaderMatcher.present_match>`.
• listener: added an option when balancing across active listeners and wildcard matching is used to return the listener that matches the IP family type associated with the listener's socket address. Any unexpected behavioral changes can be reverted by setting runtime guard envoy.reloadable_features.listener_wildcard_match_ip_family to false.
• listener: respect the :ref:`connection balance config <envoy_v3_api_field_config.listener.v3.Listener.connection_balance_config>` defined within the listener where the sockets are redirected to. Clear that field to restore the previous behavior.
• tcp: switched to the new connection pool by default. Any unexpected behavioral changes can be reverted by setting runtime guard envoy.reloadable_features.new_tcp_connection_pool to false.
• tracing: add option :ref:`use_request_id_for_trace_sampling <envoy_v3_api_field_extensions.request_id.uuid.v3.UuidRequestIdConfig.use_request_id_for_trace_sampling>` whether to use sampling policy based on :ref:`x-request-id<config_http_conn_man_headers_x-request-id>` or not.

Bug Fixes

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

• aws_lambda: if payload_passthrough is set to false, the downstream response content-type header will now be set from the content-type entry in the JSON response's headers map, if present.
• cluster: delete pools when they're idle to fix unbounded memory use when using PROXY protocol upstream with tcp_proxy. This behavior can be temporarily reverted by setting the envoy.reloadable_features.conn_pool_delete_when_idle runtime guard to false.
• cluster: fixed the :ref:`cluster stats <config_cluster_manager_cluster_stats_request_response_sizes>` histograms by moving the accounting into the router filter. This means that we now properly compute the number of bytes sent as well as handling retries which were previously ignored.
• hot_restart: fix double counting of server.seconds_until_first_ocsp_response_expiring and server.days_until_first_cert_expiring during hot-restart. This stat was only incorrect until the parent process terminated.
• http: fix erroneous handling of invalid nghttp2 frames with the NGHTTP2_ERR_REFUSED_STREAM error. Prior to the fix, Envoy would close the entire connection when nghttp2 triggered the invalid frame callback for the said error. The fix will cause Envoy to terminate just the refused stream and retain the connection. This behavior can be temporarily reverted by setting the envoy.reloadable_features.http2_consume_stream_refused_errors runtime guard to false.
• http: port stripping now works for CONNECT requests, though the port will be restored if the CONNECT request is sent upstream. This behavior can be temporarily reverted by setting envoy.reloadable_features.strip_port_from_connect to false.
• http: raise max configurable max_request_headers_kb limit to 8192 KiB (8MiB) from 96 KiB in http connection manager.
• jwt_authn: unauthorized responses now correctly include a www-authenticate header.
• listener: fix the crash which could happen when the ongoing filter chain only listener update is followed by the listener removal or full listener update.
• udp: limit each UDP listener to read maxmium 6000 packets per event loop. This behavior can be temporarily reverted by setting envoy.reloadable_features.udp_per_event_loop_read_limit to false.
• validation: fix an issue that causes TAP sockets to panic during config validation mode.
• xray: fix the default sampling 'rate' for AWS X-Ray tracer extension to be 5% as opposed to 50%.
• zipkin: fix timestamp serializaiton in annotations. A prior bug fix exposed an issue with timestamps being serialized as strings.

Removed Config or Runtime

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

• event: removed envoy.reloadable_features.activate_timers_next_event_loop runtime guard and legacy code path.
• gzip: removed legacy HTTP Gzip filter and runtime guard envoy.deprecated_features.allow_deprecated_gzip_http_filter.
• http: removed envoy.reloadable_features.allow_500_after_100 runtime guard and the legacy code path.
• http: removed envoy.reloadable_features.always_apply_route_header_rules runtime guard and legacy code path.
• http: removed envoy.reloadable_features.hcm_stream_error_on_invalid_message for disabling closing HTTP/1.1 connections on error. Connection-closing can still be disabled by setting the HTTP/1 configuration :ref:`override_stream_error_on_invalid_http_message <envoy_v3_api_field_config.core.v3.Http1ProtocolOptions.override_stream_error_on_invalid_http_message>`.
• http: removed envoy.reloadable_features.http_set_copy_replace_all_headers runtime guard and legacy code paths.
• http: removed envoy.reloadable_features.overload_manager_disable_keepalive_drain_http2; Envoy will now always send GOAWAY to HTTP2 downstreams when the :ref:`disable_keepalive <config_overload_manager_overload_actions>` overload action is active.
• http: removed envoy.reloadable_features.http_match_on_all_headers runtime guard and legacy code paths.
• http: removed envoy.reloadable_features.unify_grpc_handling runtime guard and legacy code paths.
• tls: removed envoy.reloadable_features.tls_use_io_handle_bio runtime guard and legacy code path.

New Features

• access_log: added the new response flag for :ref:`overload manager termination <envoy_v3_api_field_data.accesslog.v3.ResponseFlags.overload_manager>`. The response flag will be set when the http stream is terminated by overload manager.
• admission control: added :ref:`admission control <envoy_v3_api_field_extensions.filters.http.admission_control.v3alpha.AdmissionControl.rps_threshold>` option that when average RPS of the sampling window is below this threshold, the filter will not throttle requests. Added :ref:`admission control <envoy_v3_api_field_extensions.filters.http.admission_control.v3alpha.AdmissionControl.max_rejection_probability>` option to set an upper limit on the probability of rejection.
• bandwidth_limit: added new :ref:`HTTP bandwidth limit filter <config_http_filters_bandwidth_limit>`.
• bootstrap: added :ref:`dns_resolution_config <envoy_v3_api_field_config.bootstrap.v3.Bootstrap.dns_resolution_config>` to aggregate all of the DNS resolver configuration in a single message. By setting one such configuration option no_default_search_domain as true the DNS resolver will not use the default search domains. And by setting the configuration resolvers we can specify the external DNS servers to be used for external DNS query.
• cluster: added :ref:`dns_resolution_config <envoy_v3_api_field_config.cluster.v3.Cluster.dns_resolution_config>` to aggregate all of the DNS resolver configuration in a single message. By setting one such configuration option no_default_search_domain as true the DNS resolver will not use the default search domains.
• cluster: added :ref:`host_rewrite_literal <envoy_v3_api_field_config.route.v3.WeightedCluster.ClusterWeight.host_rewrite_literal>` to WeightedCluster.
• cluster: added :ref:`wait_for_warm_on_init <envoy_v3_api_field_config.cluster.v3.Cluster.wait_for_warm_on_init>`, which allows cluster readiness to not block on cluster warm-up. It is true by default, which preserves existing behavior. Currently, only applicable for DNS-based clusters.
• composite filter: can now be used with filters that also add an access logger, such as the WASM filter.
• config: added stat :ref:`config_reload_time_ms <subscription_statistics>`.
• connection_limit: added new :ref:`Network connection limit filter <config_network_filters_connection_limit>`.
• crash support: restore crash context when continuing to processing requests or responses as a result of an asynchronous callback that invokes a filter directly. This is unlike the call stacks that go through the various network layers, to eventually reach the filter. For a concrete example see: Envoy::Extensions::HttpFilters::Cache::CacheFilter::getHeaders which posts a callback on the dispatcher that will invoke the filter directly.
• dns cache: added :ref:`preresolve_hostnames <envoy_v3_api_field_extensions.common.dynamic_forward_proxy.v3.DnsCacheConfig.preresolve_hostnames>` option to the DNS cache config. This option allows hostnames to be preresolved into the cache upon cache creation. This might provide performance improvement, in the form of cache hits, for hostnames that are going to be resolved during steady state and are known at config load time.
• dns cache: added :ref:`dns_query_timeout <envoy_v3_api_field_extensions.common.dynamic_forward_proxy.v3.DnsCacheConfig.dns_query_timeout>` option to the DNS cache config. This option allows explicitly controlling the timeout of underlying queries independently of the underlying DNS platform implementation. Coupled with success and failure retry policies the use of this timeout will lead to more deterministic DNS resolution times.
• dns resolver: added DnsResolverOptions protobuf message to reconcile all of the DNS lookup option flags. By setting the configuration option :ref:`use_tcp_for_dns_lookups <envoy_v3_api_field_config.core.v3.DnsResolverOptions.use_tcp_for_dns_lookups>` as true we can make the underlying dns resolver library to make only TCP queries to the DNS servers and by setting the configuration option :ref:`no_default_search_domain <envoy_v3_api_field_config.core.v3.DnsResolverOptions.no_default_search_domain>` as true the DNS resolver library will not use the default search domains.
• dns resolver: added DnsResolutionConfig to combine :ref:`dns_resolver_options <envoy_v3_api_field_config.core.v3.DnsResolutionConfig.dns_resolver_options>` and :ref:`resolvers <envoy_v3_api_field_config.core.v3.DnsResolutionConfig.resolvers>` in a single protobuf message. The field resolvers can be specified with a list of DNS resolver addresses. If specified, DNS client library will perform resolution via the underlying DNS resolvers. Otherwise, the default system resolvers (e.g., /etc/resolv.conf) will be used.
• dns_filter: added :ref:`dns_resolution_config <envoy_v3_api_field_extensions.filters.udp.dns_filter.v3alpha.DnsFilterConfig.ClientContextConfig.dns_resolution_config>` to aggregate all of the DNS resolver configuration in a single message. By setting the configuration option use_tcp_for_dns_lookups to true we can make dns filter's external resolvers to answer queries using TCP only, by setting the configuration option no_default_search_domain as true the DNS resolver will not use the default search domains. And by setting the configuration resolvers we can specify the external DNS servers to be used for external DNS query which replaces the pre-existing alpha api field upstream_resolvers.
• dynamic_forward_proxy: added :ref:`dns_resolution_config <envoy_v3_api_field_extensions.common.dynamic_forward_proxy.v3.DnsCacheConfig.dns_resolution_config>` option to the DNS cache config in order to aggregate all of the DNS resolver configuration in a single message. By setting one such configuration option no_default_search_domain as true the DNS resolver will not use the default search domains. And by setting the configuration resolvers we can specify the external DNS servers to be used for external DNS query instead of the system default resolvers.
• ext_authz_filter: added :ref:`bootstrap_metadata_labels_key <envoy_v3_api_field_extensions.filters.http.ext_authz.v3.ExtAuthz.bootstrap_metadata_labels_key>` option to configure labels of destination service.
• http: a new field is_optional is added to extensions.filters.network.http_connection_manager.v3.HttpFilter. When value is true, the unsupported http filter will be ignored by envoy. This is also same with unsupported http filter in the typed per filter config. For more information, please reference :ref:`HttpFilter <envoy_v3_api_field_extensions.filters.network.http_connection_manager.v3.HttpFilter.is_optional>`.
• http: added :ref``scheme options <envoy_v3_api_field_extensions.filters.network.http_connection_manager.v3.HttpConnectionManager.scheme>` for adding or overwriting scheme.
• http: added :ref:`stripping trailing host dot from host header <envoy_v3_api_field_extensions.filters.network.http_connection_manager.v3.HttpConnectionManager.strip_trailing_host_dot>` support.
• http: added support for :ref:`original IP detection extensions <envoy_v3_api_field_extensions.filters.network.http_connection_manager.v3.HttpConnectionManager.original_ip_detection_extensions>`. Two initial extensions were added, the :ref:`custom header <envoy_v3_api_msg_extensions.http.original_ip_detection.custom_header.v3.CustomHeaderConfig>` extension and the :ref:`xff <envoy_v3_api_msg_extensions.http.original_ip_detection.xff.v3.XffConfig>` extension.
• http: added a new option to upstream HTTP/2 :ref:`keepalive <envoy_v3_api_field_config.core.v3.Http2ProtocolOptions.connection_keepalive>` to send a PING ahead of a new stream if the connection has been idle for a sufficient duration.
• http: added the ability to :ref:`unescape slash sequences <envoy_v3_api_field_extensions.filters.network.http_connection_manager.v3.HttpConnectionManager.path_with_escaped_slashes_action>` in the path. Requests with unescaped slashes can be proxied, rejected or redirected to the new unescaped path. By default this feature is disabled. The default behavior can be overridden through :ref:`http_connection_manager.path_with_escaped_slashes_action<config_http_conn_man_runtime_path_with_escaped_slashes_action>` runtime variable. This action can be selectively enabled for a portion of requests by setting the :ref:`http_connection_manager.path_with_escaped_slashes_action_sampling<config_http_conn_man_runtime_path_with_escaped_slashes_action_enabled>` runtime variable.
• http: added upstream and downstream alpha HTTP/3 support! See :ref:`quic_options <envoy_v3_api_field_config.listener.v3.UdpListenerConfig.quic_options>` for downstream and the new http3_protocol_options in :ref:`http_protocol_options <envoy_v3_api_msg_extensions.upstreams.http.v3.HttpProtocolOptions>` for upstream HTTP/3.
• input matcher: a new input matcher that :ref:`matches an IP address against a list of CIDR ranges <envoy_v3_api_file_envoy/extensions/matching/input_matchers/ip/v3/ip.proto>`.
• jwt_authn: added support to fetch remote jwks asynchronously specified by :ref:`async_fetch <envoy_v3_api_field_extensions.filters.http.jwt_authn.v3.RemoteJwks.async_fetch>`.
• jwt_authn: added support to add padding in the forwarded JWT payload specified by :ref:`pad_forward_payload_header <envoy_v3_api_field_extensions.filters.http.jwt_authn.v3.JwtProvider.pad_forward_payload_header>`.
• listener: added ability to change an existing listener's address.
• listener: added filter chain match support for :ref:`direct source address <envoy_v3_api_field_config.listener.v3.FilterChainMatch.direct_source_prefix_ranges>`.
• local_rate_limit_filter: added suppoort for locally rate limiting http requests on a per connection basis. This can be enabled by setting the :ref:`local_rate_limit_per_downstream_connection <envoy_v3_api_field_extensions.filters.http.local_ratelimit.v3.LocalRateLimit.local_rate_limit_per_downstream_connection>` field to true.
• metric service: added support for sending metric tags as labels. This can be enabled by setting the :ref:`emit_tags_as_labels <envoy_v3_api_field_config.metrics.v3.MetricsServiceConfig.emit_tags_as_labels>` field to true.
• proxy protocol: added support for generating the header while using the :ref:`HTTP connection manager <config_http_conn_man>`. This is done using the using the :ref:`Proxy Protocol Transport Socket <extension_envoy.transport_sockets.upstream_proxy_protocol>` on upstream clusters. This feature is currently affected by a memory leak issue.
• req_without_query: added access log formatter extension implementing command operator :ref:`REQ_WITHOUT_QUERY <envoy_v3_api_msg_extensions.formatter.req_without_query.v3.ReqWithoutQuery>` to log the request path, while excluding the query string.
• router: added flag suppress_grpc_request_failure_code_stats to :ref:`key <envoy_v3_api_msg_extensions.filters.http.router.v3.Router>` to allow users to exclude incrementing HTTP status code stats on gRPC requests.
• stats: added native :ref:`Graphite-formatted tag <envoy_v3_api_msg_extensions.stat_sinks.graphite_statsd.v3.GraphiteStatsdSink>` support.
• tcp: added support for :ref:`preconnecting <v1.18.0:envoy_v3_api_msg_config.cluster.v3.Cluster.PreconnectPolicy>`. Preconnecting is off by default, but recommended for clusters serving latency-sensitive traffic.
• thrift_proxy: added per upstream metrics within the :ref:`thrift router <envoy_v3_api_msg_extensions.filters.network.thrift_proxy.router.v3.Router>` for request and response size histograms.
• thrift_proxy: added support for :ref:`outlier detection <arch_overview_outlier_detection>`.
• tls: allow dual ECDSA/RSA certs via SDS. Previously, SDS only supported a single certificate per context, and dual cert was only supported via non-SDS.
• udp_proxy: added :ref:`key <envoy_v3_api_msg_extensions.filters.udp.udp_proxy.v3.UdpProxyConfig.HashPolicy>` as another hash policy to support hash based routing on any given key.
• windows container image: added user, EnvoyUser which is part of the Network Configuration Operators group to the container image.

Deprecated

• bootstrap: the field :ref:`use_tcp_for_dns_lookups <envoy_v3_api_field_config.bootstrap.v3.Bootstrap.use_tcp_for_dns_lookups>` is deprecated in favor of :ref:`dns_resolution_config <envoy_v3_api_field_config.bootstrap.v3.Bootstrap.dns_resolution_config>` which aggregates all of the DNS resolver configuration in a single message.
• cluster: the fields :ref:`use_tcp_for_dns_lookups <envoy_v3_api_field_config.cluster.v3.Cluster.use_tcp_for_dns_lookups>` and :ref:`dns_resolvers <envoy_v3_api_field_config.cluster.v3.Cluster.dns_resolvers>` are deprecated in favor of :ref:`dns_resolution_config <envoy_v3_api_field_config.cluster.v3.Cluster.dns_resolution_config>` which aggregates all of the DNS resolver configuration in a single message.
• dns_filter: the field :ref:`known_suffixes <envoy_v3_api_field_data.dns.v3.DnsTable.known_suffixes>` is deprecated. The internal data management of the filter has changed and the filter no longer uses the known_suffixes field.
• dynamic_forward_proxy: the field :ref:`use_tcp_for_dns_lookups <envoy_v3_api_field_extensions.common.dynamic_forward_proxy.v3.DnsCacheConfig.use_tcp_for_dns_lookups>` is deprecated in favor of :ref:`dns_resolution_config <envoy_v3_api_field_extensions.common.dynamic_forward_proxy.v3.DnsCacheConfig.dns_resolution_config>` which aggregates all of the DNS resolver configuration in a single message.
• http: :ref:`xff_num_trusted_hops <envoy_v3_api_field_extensions.filters.network.http_connection_manager.v3.HttpConnectionManager.xff_num_trusted_hops>` is deprecated in favor of :ref:`original IP detection extensions<envoy_v3_api_field_extensions.filters.network.http_connection_manager.v3.HttpConnectionManager.original_ip_detection_extensions>`.