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."],[[["The latest version available for `BackendServiceConnectionTrackingPolicy.Types.ConnectionPersistenceOnUnhealthyBackends` is 3.6.0, with multiple previous versions also documented, starting from version 1.0.0."],["This documentation provides reference information and code samples for the Compute Engine v1 API enum `BackendServiceConnectionTrackingPolicy.Types.ConnectionPersistenceOnUnhealthyBackends`."],["The enum specifies connection persistence behavior when backends become unhealthy, with options including `DEFAULT_FOR_PROTOCOL`, `NEVER_PERSIST`, and `ALWAYS_PERSIST`."],["The `DEFAULT_FOR_PROTOCOL` setting allows existing connections to persist on unhealthy backends for TCP and SCTP protocols when tracking mode is `PER_CONNECTION` or Session Affinity is configured, while `NEVER_PERSIST` diverts connections to healthy backends, and `ALWAYS_PERSIST` keeps existing connections regardless of health status."],["There is an additional `UndefinedConnectionPersistenceOnUnhealthyBackends` field, which denotes a value indicating that the enum field is not set."]]],[]]
