Reference documentation and code samples for the Compute Engine v1 API enum TargetPool.Types.SessionAffinity.
Session affinity option, must be one of the following values: NONE: Connections from the same client IP may go to any instance in the pool. CLIENT_IP: Connections from the same client IP will go to the same instance in the pool while that instance remains healthy. CLIENT_IP_PROTO: Connections from the same client IP with the same IP protocol will go to the same instance in the pool while that instance remains healthy.
2-tuple hash on packet's source and destination IP addresses. Connections from the same source IP address to the same destination IP address will be served by the same backend VM while that VM remains healthy.
ClientIpNoDestination
1-tuple hash only on packet's source IP address. Connections from the same source IP address will be served by the same backend VM while that VM remains healthy. This option can only be used for Internal TCP/UDP Load Balancing.
ClientIpPortProto
5-tuple hash on packet's source and destination IP addresses, IP protocol, and source and destination ports. Connections for the same IP protocol from the same source IP address and port to the same destination IP address and port will be served by the same backend VM while that VM remains healthy. This option cannot be used for HTTP(S) load balancing.
ClientIpProto
3-tuple hash on packet's source and destination IP addresses, and IP protocol. Connections for the same IP protocol from the same source IP address to the same destination IP address will be served by the same backend VM while that VM remains healthy. This option cannot be used for HTTP(S) load balancing.
GeneratedCookie
Hash based on a cookie generated by the L7 loadbalancer. Only valid for HTTP(S) load balancing.
HeaderField
The hash is based on a user specified header field.
HttpCookie
The hash is based on a user provided cookie.
None
No session affinity. Connections from the same client IP may go to any instance in the pool.
UndefinedSessionAffinity
A value indicating that the enum field is not set.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-08 UTC."],[[["\u003cp\u003eThis document provides versioned reference documentation for the \u003ccode\u003eTargetPool.Types.SessionAffinity\u003c/code\u003e enum within the Google Cloud Compute Engine v1 API, with version 3.6.0 being the latest.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eTargetPool.Types.SessionAffinity\u003c/code\u003e enum defines various options for session affinity, which determines how connections are routed to instances within a target pool.\u003c/p\u003e\n"],["\u003cp\u003eThe available session affinity options include \u003ccode\u003eNONE\u003c/code\u003e, \u003ccode\u003eCLIENT_IP\u003c/code\u003e, \u003ccode\u003eCLIENT_IP_PROTO\u003c/code\u003e, \u003ccode\u003eCLIENT_IP_PORT_PROTO\u003c/code\u003e, \u003ccode\u003eCLIENT_IP_NO_DESTINATION\u003c/code\u003e, \u003ccode\u003eGENERATED_COOKIE\u003c/code\u003e, \u003ccode\u003eHEADER_FIELD\u003c/code\u003e, \u003ccode\u003eHTTP_COOKIE\u003c/code\u003e, and \u003ccode\u003eUNDEFINED_SESSION_AFFINITY\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eEach session affinity option uses a different hashing method (e.g., 2-tuple, 3-tuple, 5-tuple) based on IP addresses, protocols, and/or ports, with certain options having restrictions on their usage with HTTP(S) load balancing.\u003c/p\u003e\n"],["\u003cp\u003eThe document contains a list of versioned links starting from version 1.0.0 all the way to the latest 3.6.0, allowing users to consult on a specific version for the TargetPool.Types.SessionAffinity enum.\u003c/p\u003e\n"]]],[],null,[]]
