{"record":{"id":"88c6d98e79509881","repo":"xai-org/x-algorithm","slug":"timed-out-after-s","errorCode":null,"errorMessage":"timed out after {}s","messagePattern":"timed out after (.+?)s","errorType":"error_code","errorClass":"VfChannelError::Connect","httpStatus":null,"severity":"error","filePath":"visibility-filtering-client/discovery.rs","lineNumber":139,"sourceCode":"    Xds(LoadBalancedChannel),\n}\n\npub(crate) async fn build_vf_channel(\n    params: &VfChannelParams<'_>,\n) -> Result<VfChannel, VfChannelError> {\n    let name = params.name;\n    match params.discovery {\n        VfDiscovery::Wily => Ok(VfChannel::Wily(build_vf_wily_channel(params).await?)),\n        VfDiscovery::Xds => {\n            let listener = vf_xds_listener_from_env();\n            let result = match tokio::time::timeout(\n                VF_XDS_BUILD_TIMEOUT,\n                build_xds_channel(params, &listener),\n            )\n            .await\n            {\n                Ok(result) => result,\n                Err(_) => Err(VfChannelError::Connect(anyhow::anyhow!(\n                    \"timed out after {}s\",\n                    VF_XDS_BUILD_TIMEOUT.as_secs()\n                ))),\n            };\n            match result {\n                Ok(channel) => {\n                    incr_build_metric(name, \"xds\", \"built\");\n                    Ok(VfChannel::Xds(channel))\n                }\n                Err(e) => {\n                    warn!(\n                        channel = name,\n                        listener = %listener,\n                        error = %e,\n                        \"VF xDS channel build failed\"\n                    );\n                    incr_build_metric(name, \"xds\", \"failed\");\n                    Err(e)","sourceCodeStart":121,"sourceCodeEnd":157,"githubUrl":"https://github.com/xai-org/x-algorithm/blob/24c60942c5c5fdad3a6addffb4c6e6d2f228f04f/visibility-filtering-client/discovery.rs#L121-L157","documentation":"Returned in build_vf_channel when building the xDS channel for the visibility-filtering (VF) service exceeds VF_XDS_BUILD_TIMEOUT (the message states the timeout in seconds). The future build_xds_channel(params, &listener) was wrapped in a timeout and the deadline elapsed before the channel was ready.","triggerScenarios":"Calling build_vf_channel when xDS discovery is slow: unreachable xDS server, slow TLS handshake, large listener/config download, DNS resolution delays, or an overloaded control plane — anything making channel construction outlast VF_XDS_BUILD_TIMEOUT.","commonSituations":"xDS server down or misconfigured in the environment; network policies blocking gRPC/xDS ports in containers; cold start downloading big configs; control plane degradation during incidents.","solutions":["Check connectivity to the xDS server (host:port reachability, TLS certs valid)","Increase VF_XDS_BUILD_TIMEOUT if the environment legitimately needs longer (large configs, high latency)","Retry the build with backoff — transient xDS/control-plane slowness is common at startup","Verify xDS auth material (certs/tokens) referenced by params is present and unexpired"],"exampleFix":"// before\nconst VF_XDS_BUILD_TIMEOUT: Duration = Duration::from_secs(5);\n\n// after\nconst VF_XDS_BUILD_TIMEOUT: Duration = Duration::from_secs(\n    std::env::var(\"VF_XDS_BUILD_TIMEOUT_SECS\").ok().and_then(|v| v.parse().ok()).unwrap_or(15),\n);","handlingStrategy":"retry","validationCode":"// preflight: TCP-connect to xDS host:port before building the channel","typeGuard":null,"tryCatchPattern":"for attempt in 0..3 { match build_vf_channel(params).await { Ok(c) => break Ok(c), Err(e) if attempt < 2 => sleep_backoff(attempt), Err(e) => break Err(e) } }","preventionTips":["Make the xDS timeout configurable per environment","Start channel building early (background task) before serving","Monitor xDS connection metrics"],"tags":["grpc","xds","timeout","channel-init","rust"],"backgroundTag":"grpc-channel-setup-timeout","analyzedSha":"24c60942c5c5fdad3a6addffb4c6e6d2f228f04f","analyzedAt":"2026-08-28T11:40:14.686Z","schemaVersion":2},"datasetVersion":"2026-08-28T16:17:29.566Z"}