alibaba/nacos · error · RuntimeException

Informer serviceInformer sync timed out

Error message

Informer serviceInformer sync timed out

What it means

Error "Informer serviceInformer sync timed out" thrown in alibaba/nacos.

Source

Thrown at k8s-sync/src/main/java/com/alibaba/nacos/k8s/sync/K8sSyncServer.java:290

                        instanceOperatorClient.listAllInstances(namespace, serviceName);
                    unregisterInstances(deleteIpSet, namespace, serviceName, oldInstanceList);
                    Loggers.MAIN.info("delete instances, namespace:" + namespace + ", serviceName: "
                        + serviceName);
                } catch (NacosException e) {
                    Loggers.MAIN.info("delete instances fail, namespace:" + namespace
                        + ", serviceName: " + serviceName);
                }
            }
        });
        
        // Wait until the cache of each informer has been fully synced before proceeding.
        // This ensures that the local cache contains the latest and complete resource data.
        long timeout = 30000L;
        long startTime = System.currentTimeMillis();
        serviceInformer.run();
        while (!serviceInformer.hasSynced()) {
            if (System.currentTimeMillis() - startTime > timeout) {
                throw new RuntimeException("Informer serviceInformer sync timed out");
            }
            ThreadUtils.sleep(100L);
        }
        startTime = System.currentTimeMillis();
        endpointInformer.run();
        while (!endpointInformer.hasSynced()) {
            if (System.currentTimeMillis() - startTime > timeout) {
                throw new RuntimeException("Informer endpointInformer sync timed out");
            }
            ThreadUtils.sleep(100L);
        }
    }
    
    /**
     * create instance.
     *
     * @param ip instance ip
     * @param targetPort instance port

View on GitHub (pinned to 9b989acdf1)

Solutions

1. Review the input and runtime state for k8s service informer sync timeout, correct the reported problem, and retry.

When it happens

Trigger: Thrown at k8s-sync/src/main/java/com/alibaba/nacos/k8s/sync/K8sSyncServer.java:290 when the library encounters an invalid state.

Common situations: The Kubernetes service informer failed to sync within the timeout.

Understand the failure class

• Timeouts: ETIMEDOUT, deadlines, and hung requests — what actually expires when a request times out.

AI-assisted analysis of alibaba/nacos@9b989acdf1 (2026-08-14). Data as JSON: /api/errors/6292db1fc3b115f0. Report an issue: GitHub.