fix(kube-proxy): honor sessionAffinity=ClientIP for ClusterIP and NodePort#42
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indyjonesnl wants to merge 1 commit into
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fix(kube-proxy): honor sessionAffinity=ClientIP for ClusterIP and NodePort#42indyjonesnl wants to merge 1 commit into
indyjonesnl wants to merge 1 commit into
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…ePort iptables-mode kube-proxy now produces sticky DNAT rules for any service with sessionAffinity=ClientIP, regardless of endpoint count, and the recent --set is collapsed into the same rule as DNAT so the match only fires for packets that actually DNAT (correct protocol/port) — matching upstream K8s pkg/proxy/iptables/proxier.go writeServiceToEndpointRules. The api-server now defaults sessionAffinityConfig.clientIP.timeoutSeconds to 10800s (3h) when sessionAffinity is ClientIP and no timeout was given, and clears the config when affinity is switched to None on update, per K8s pkg/apis/core/v1/defaults.go SetDefaults_Service. Adds unit tests covering ClusterIP affinity (multi- and single-endpoint), NodePort affinity, no-affinity service, and the xt_recent-unavailable fallback path. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Problem
`Service.spec.sessionAffinity = ClientIP` was ignored by our kube-proxy iptables rules. Traffic was always round-robin across backends, breaking conformance tests that assert client-affinity stickiness within the configured timeout window.
Fix
Translate `sessionAffinity: ClientIP` into iptables `-m recent` rules that record the client source IP on first match and re-route subsequent packets from the same source to the same backend within `sessionAffinityConfig.clientIP.timeoutSeconds` (default 10800s). Applies to both ClusterIP and NodePort services.
Verification
`cargo build --workspace --locked` clean. Depends on #32 for green CI.