Reference documentation and code samples for the Compute Engine v1 API enum BackendServiceConnectionTrackingPolicy.Types.ConnectionPersistenceOnUnhealthyBackends.
Specifies connection persistence when backends are unhealthy. The default value is DEFAULT_FOR_PROTOCOL. If set to DEFAULT_FOR_PROTOCOL, the existing connections persist on unhealthy backends only for connection-oriented protocols (TCP and SCTP) and only if the Tracking Mode is PER_CONNECTION (default tracking mode) or the Session Affinity is configured for 5-tuple. They do not persist for UDP. If set to NEVER_PERSIST, after a backend becomes unhealthy, the existing connections on the unhealthy backend are never persisted on the unhealthy backend. They are always diverted to newly selected healthy backends (unless all backends are unhealthy). If set to ALWAYS_PERSIST, existing connections always persist on unhealthy backends regardless of protocol and session affinity. It is generally not recommended to use this mode overriding the default. For more details, see Connection Persistence for Network Load Balancing and Connection Persistence for Internal TCP/UDP Load Balancing.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-03-24 UTC."],[[["This page provides documentation for the `BackendServiceConnectionTrackingPolicy.Types.ConnectionPersistenceOnUnhealthyBackends` enum in the Google Cloud Compute Engine v1 API."],["The latest version documented is 3.6.0, with a range of versions from 1.0.0 up to this version being available for viewing."],["The enum defines how connection persistence is handled when backends become unhealthy, with options such as `AlwaysPersist`, `NeverPersist`, and `DefaultForProtocol`."],["The default behavior (`DefaultForProtocol`) allows existing connections to persist on unhealthy backends only for connection-oriented protocols like TCP and SCTP if the tracking mode is PER_CONNECTION, or session affinity is configured for 5-tuple, otherwise they are not persistent."],["The `UndefinedConnectionPersistenceOnUnhealthyBackends` field indicates that the enum field is not set, indicating that the default behavior is active."]]],[]]
