Changes that are expected to cause an incompatibility if applicable; deployment changes are likely required
Changes that may cause incompatibilities for some users, but should not for most
- build: the Alpine based debug images are no longer built in CI, use Ubuntu based images instead.
- ext_authz filter: the deprecated field :ref:`use_alpha <envoy_api_field_config.filter.http.ext_authz.v2.ExtAuthz.use_alpha>` is no longer supported and cannot be set anymore.
Changes expected to improve the state of the world and are unlikely to have negative effects
- http: sending CONNECT_ERROR for HTTP/2 where appropriate during CONNECT requests.
Normally occurs at the end of the :ref:`deprecation period <deprecated>`
- ext_authz: removed auto ignore case in HTTP-based ext_authz header matching and the runtime guard envoy.reloadable_features.ext_authz_http_service_enable_case_sensitive_string_matcher. To ignore case, set the :ref:`ignore_case <envoy_api_field_type.matcher.StringMatcher.ignore_case>` field to true.
- http: removed envoy.reloadable_features.http1_flood_protection and legacy code path for turning flood protection off.
- grpc: implemented header value syntax support when defining :ref:`initial metadata <envoy_v3_api_field_config.core.v3.GrpcService.initial_metadata>` for gRPC-based ext_authz :ref:`HTTP <envoy_v3_api_field_extensions.filters.http.ext_authz.v3.ExtAuthz.grpc_service>` and :ref:`network <envoy_v3_api_field_extensions.filters.network.ext_authz.v3.ExtAuthz.grpc_service>` filters, and :ref:`ratelimit <envoy_v3_api_field_config.ratelimit.v3.RateLimitServiceConfig.grpc_service>` filters.
- hds: added support for delta updates in the :ref:`HealthCheckSpecifier <envoy_v3_api_msg_service.health.v3.HealthCheckSpecifier>`, making only the Endpoints and Health Checkers that changed be reconstructed on receiving a new message, rather than the entire HDS.
- health_check: added option to use :ref:`no_traffic_healthy_interval <envoy_v3_api_field_config.core.v3.HealthCheck.no_traffic_healthy_interval>` which allows a different no traffic interval when the host is healthy.
- mongo_proxy: the list of commands to produce metrics for is now :ref:`configurable <envoy_v3_api_field_extensions.filters.network.mongo_proxy.v3.MongoProxy.commands>`.
- ratelimit: added :ref:`disable_x_envoy_ratelimited_header <envoy_v3_api_msg_extensions.filters.http.ratelimit.v3.RateLimit>` option to disable X-Envoy-RateLimited header.
- tcp: added a new :ref:`envoy.overload_actions.reject_incoming_connections <config_overload_manager_overload_actions>` action to reject incoming TCP connections.