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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-08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 reference documentation for the \u003ccode\u003eTargetPool.Types.SessionAffinity\u003c/code\u003e enum within the Google Compute Engine v1 API, covering versions from 1.0.0 to the latest 3.6.0.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eSessionAffinity\u003c/code\u003e enum defines different options for how connections are directed to instances in a target pool, based on client IP, protocol, and other parameters.\u003c/p\u003e\n"],["\u003cp\u003eThere are several session affinity options like \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 and others that involve various hashing methods or a cookie.\u003c/p\u003e\n"],["\u003cp\u003eEach session affinity option has specific use cases and restrictions, such as certain options not being available for HTTP(S) load balancing.\u003c/p\u003e\n"],["\u003cp\u003eThe document details the fields within the enum, including descriptions for \u003ccode\u003eClientIp\u003c/code\u003e, \u003ccode\u003eClientIpNoDestination\u003c/code\u003e, \u003ccode\u003eClientIpPortProto\u003c/code\u003e, \u003ccode\u003eClientIpProto\u003c/code\u003e, \u003ccode\u003eGeneratedCookie\u003c/code\u003e, \u003ccode\u003eHeaderField\u003c/code\u003e, \u003ccode\u003eHttpCookie\u003c/code\u003e, \u003ccode\u003eNone\u003c/code\u003e, and \u003ccode\u003eUndefinedSessionAffinity\u003c/code\u003e.\u003c/p\u003e\n"]]],[],null,[]]
