diff --git a/rpcman-core/src/main/java/cn/ipman/rpc/core/consumer/HttpInvoker.java b/rpcman-core/src/main/java/cn/ipman/rpc/core/consumer/HttpInvoker.java
index 76356b9..ccf690d 100644
--- a/rpcman-core/src/main/java/cn/ipman/rpc/core/consumer/HttpInvoker.java
+++ b/rpcman-core/src/main/java/cn/ipman/rpc/core/consumer/HttpInvoker.java
@@ -60,7 +60,6 @@ static <T> T httpGet(String url, Class<T> clazz) {
 
 
     @SneakyThrows
-    @SuppressWarnings("unused")
     static <T> T httpGet(String url, TypeReference<T> typeReference) {
         log.debug(" =====>>>>>> httpGet: " + url);
         String respJson = Default.get(url);
@@ -68,7 +67,6 @@ static <T> T httpGet(String url, TypeReference<T> typeReference) {
         return JSON.parseObject(respJson, typeReference);
     }
 
-
     /**
      * 使用HTTP POST方法发送请求，并将其解析为指定的Java类型。
      *
diff --git a/rpcman-core/src/main/java/cn/ipman/rpc/core/registry/ipman/IpManHeathChecker.java b/rpcman-core/src/main/java/cn/ipman/rpc/core/registry/ipman/IpManHeathChecker.java
new file mode 100644
index 0000000..662a7e4
--- /dev/null
+++ b/rpcman-core/src/main/java/cn/ipman/rpc/core/registry/ipman/IpManHeathChecker.java
@@ -0,0 +1,43 @@
+package cn.ipman.rpc.core.registry.ipman;
+
+import lombok.extern.slf4j.Slf4j;
+
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Description for this class
+ *
+ * @Author IpMan
+ * @Date 2024/4/21 20:12
+ */
+@Slf4j
+public class IpManHeathChecker {
+
+    // 注册中心探活间隔, 5s
+    final int interval = 5_000;
+
+    final ScheduledExecutorService executor = Executors.newScheduledThreadPool(1);
+
+    static final DateTimeFormatter DTF = DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss");
+
+    public void check(Callback callback) {
+        executor.scheduleWithFixedDelay(() -> {
+            log.debug(" schedule to check ipman registry ... [{}]", DTF.format(LocalDateTime.now()));
+            try {
+                callback.call();
+            } catch (Exception e) {
+                throw new RuntimeException(e);
+            }
+        }, interval, interval, TimeUnit.MILLISECONDS);
+    }
+
+
+    @FunctionalInterface
+    public interface Callback {
+        void call() throws Exception;
+    }
+}
diff --git a/rpcman-core/src/main/java/cn/ipman/rpc/core/registry/ipman/IpManRegistryCenter.java b/rpcman-core/src/main/java/cn/ipman/rpc/core/registry/ipman/IpManRegistryCenter.java
index e4d3a82..e158ac9 100644
--- a/rpcman-core/src/main/java/cn/ipman/rpc/core/registry/ipman/IpManRegistryCenter.java
+++ b/rpcman-core/src/main/java/cn/ipman/rpc/core/registry/ipman/IpManRegistryCenter.java
@@ -1,9 +1,13 @@
 package cn.ipman.rpc.core.registry.ipman;
 
 import cn.ipman.rpc.core.api.RegistryCenter;
+import cn.ipman.rpc.core.consumer.HttpInvoker;
 import cn.ipman.rpc.core.meta.InstanceMeta;
 import cn.ipman.rpc.core.meta.ServiceMeta;
 import cn.ipman.rpc.core.registry.ChangedListener;
+import cn.ipman.rpc.core.registry.Event;
+import com.alibaba.fastjson.JSON;
+import com.alibaba.fastjson.TypeReference;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Value;
 
@@ -38,25 +42,67 @@ public void stop() {
     @Override
     public void register(ServiceMeta service, InstanceMeta instance) {
         log.info(" ====>>>> [IpMan-Registry] : register instance {} to {}", instance.toHttpUrl(), service.toPath());
+        InstanceMeta inst = HttpInvoker.httpPost(JSON.toJSONString(instance), regPath(service), InstanceMeta.class);
+        log.info(" ====>>>> [IpMan-Registry] : registered {} success", inst);
     }
 
     @Override
     public void unregister(ServiceMeta service, InstanceMeta instance) {
-
+        log.info(" ====>>>> [IpMan-Registry] : unregister instance {} to {}", instance.toHttpUrl(), service.toPath());
+        InstanceMeta inst = HttpInvoker.httpPost(JSON.toJSONString(instance), unRegPath(service), InstanceMeta.class);
+        log.info(" ====>>>> [IpMan-Registry] : unregistered {} success", inst);
     }
 
     @Override
     public List<InstanceMeta> fetchAll(ServiceMeta service) {
-        return null;
+        log.info(" ====>>>> [IpMan-Registry] : find all instances for {}", service.toPath());
+        List<InstanceMeta> instances = HttpInvoker.httpGet(findAllPath(service), new TypeReference<List<InstanceMeta>>() {
+        });
+        log.info(" ====>>>> [IpMan-Registry] : findAll = {}", instances);
+        return instances;
     }
 
+    IpManHeathChecker heathChecker = new IpManHeathChecker();
+
     @Override
     public void subscribe(ServiceMeta service, ChangedListener listener) {
+        // 每隔5s, 去注册中心获取最新版本号,如果版本号大于当前版本, 就从注册中心同步最新实例的信息
+        heathChecker.check(() -> {
+            // 获取注册中心, 最新的版本号
+            String versionPath = versionPath(service);
+            Long newVersion = HttpInvoker.httpGet(versionPath, Long.class);
+            Long version = VERSIONS.getOrDefault(service.toPath(), -1L);
+            log.debug(" ====>>>> [{}] newVersion:{} oldVersion:{}", service.toPath(), newVersion, version);
 
+            // 如果版本号大于当前版本, 就从注册中心同步最新实例的信息
+            if (newVersion > version) {
+                log.info(" ====>>>> version changed [{}] newVersion:{} oldVersion:{}", service.toPath(), newVersion, version);
+                List<InstanceMeta> instanceMetas = fetchAll(service);
+                log.info(" ====>>>> version {} fetch all and fire: {}", newVersion, instanceMetas);
+                listener.fire(new Event(instanceMetas));
+                VERSIONS.put(service.toPath(), newVersion);
+            }
+        });
     }
 
     @Override
     public void unsubscribe() {
 
     }
+
+    private String regPath(ServiceMeta service) {
+        return server + "/reg?service=" + service.toPath();
+    }
+
+    private String unRegPath(ServiceMeta service) {
+        return server + "/unreg?service=" + service.toPath();
+    }
+
+    private String findAllPath(ServiceMeta service) {
+        return server + "/findAll?service=" + service.toPath();
+    }
+
+    private String versionPath(ServiceMeta service) {
+        return server + "/version?service=" + service.toPath();
+    }
 }