diff --git a/lib/index.js b/lib/index.js
index 0b362c9..57d56e6 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -71,6 +71,7 @@ let argv = _yargs.default.command('$0', 'start nshd').command('addr', 'show addr
 }).help('help').alias('h', 'help').wrap(Math.min(120, _yargs.default.terminalWidth())).argv;
 
 const isWindows = _os.default.platform() === 'win32';
+const clientConnectTimeout = 20000;
 const pingInterval = 20000;
 const forcePingInterval = 60000;
 const ptyCols = 120;
@@ -222,12 +223,6 @@ function getAuthorizedUser(src) {
   return null;
 }
 
-const client = new _nknSdk.default.MultiClient({
-  originalClient: true,
-  seed: wallet.getSeed(),
-  identifier: identifier
-});
-
 class Session {
   constructor(client, remoteAddr, options) {
     this.client = client;
@@ -286,10 +281,9 @@ class Session {
 
 }
 
-let sessions = {};
-client.onConnect(() => {
-  console.log('Listening at', client.addr);
+var sessions = {};
 
+function keepalive(client) {
   for (let c of Object.values(client.clients)) {
     setInterval(function () {
       try {
@@ -371,112 +365,145 @@ client.onConnect(() => {
       }, 3000);
     });
   }, forcePingInterval);
-});
-client.onMessage(async ({
-  src,
-  payload,
-  payloadType,
-  isEncrypted
-}) => {
-  if (!isEncrypted) {
-    console.log('Received unencrypted msg from', src);
-    return false;
-  }
+}
 
-  if (src.endsWith(client.getPublicKey()) && !payload) {
-    return;
-  }
+(async () => {
+  let client;
 
-  let au = getAuthorizedUser(src);
+  while (true) {
+    try {
+      client = new _nknSdk.default.MultiClient({
+        originalClient: true,
+        seed: wallet.getSeed(),
+        identifier: identifier
+      });
+    } catch (e) {
+      console.error('Create client error:', e);
+      continue;
+    }
 
-  if (!au) {
-    console.log('Received msg from unauthorized sender', src);
-    return false;
-  }
+    try {
+      await new Promise((resolve, reject) => {
+        client.onConnect(resolve);
+        setTimeout(reject, clientConnectTimeout);
+      });
+    } catch (e) {
+      console.error('Client connect timeout');
+      client.close().catch(console.error);
+      continue;
+    }
 
-  if (payloadType !== _nknSdk.default.pb.payloads.PayloadType.TEXT) {
-    console.log('Received msg with wrong payload type from', src);
-    return false;
+    break;
   }
 
-  let msg = JSON.parse(payload);
+  console.log('Listening at', client.addr);
+  keepalive(client);
+  client.onMessage(async ({
+    src,
+    payload,
+    payloadType,
+    isEncrypted
+  }) => {
+    if (!isEncrypted) {
+      console.log('Received unencrypted msg from', src);
+      return false;
+    }
 
-  if (msg.timestamp && Date.now() - Date.parse(msg.timestamp) > 60000) {
-    return false;
-  }
+    if (src.endsWith(client.getPublicKey()) && !payload) {
+      return;
+    }
 
-  let options = {
-    uid: au.uid,
-    gid: au.gid
-  };
+    let au = getAuthorizedUser(src);
 
-  if (session && msg.resize) {
-    if (!sessions[src]) {
-      sessions[src] = new Session(client, src, options);
+    if (!au) {
+      console.log('Received msg from unauthorized sender', src);
+      return false;
     }
 
-    sessions[src].resize(msg.resize);
-    console.log('Resize to', msg.resize, 'from', src);
-  }
+    if (payloadType !== _nknSdk.default.pb.payloads.PayloadType.TEXT) {
+      console.log('Received msg with wrong payload type from', src);
+      return false;
+    }
 
-  let cmd = msg.cmd || msg.content;
+    let msg = JSON.parse(payload);
 
-  if (!cmd) {
-    return false;
-  }
+    if (msg.timestamp && Date.now() - Date.parse(msg.timestamp) > 60000) {
+      return false;
+    }
+
+    let options = {
+      uid: au.uid,
+      gid: au.gid
+    };
+
+    if (session && msg.resize) {
+      if (!sessions[src]) {
+        sessions[src] = new Session(client, src, options);
+      }
 
-  console.log('Execute cmd' + (logCmd ? ' ' + cmd : ''), 'from', src);
+      sessions[src].resize(msg.resize);
+      console.log('Resize to', msg.resize, 'from', src);
+    }
 
-  if (msg.execSync) {
-    options.timeout = msg.execTimeout || syncExecTimeout;
-    let stdout, stderr;
+    let cmd = msg.cmd || msg.content;
 
-    try {
-      stdout = (0, _child_process.execSync)(cmd, options).toString();
-    } catch (e) {
-      stderr = e.stderr ? e.stderr.toString() : e.error;
+    if (!cmd) {
+      return false;
     }
 
-    return JSON.stringify({
-      stdout,
-      stderr
-    });
-  } else {
-    options.timeout = msg.execTimeout || asyncExecTimeout;
+    console.log('Execute cmd' + (logCmd ? ' ' + cmd : ''), 'from', src);
 
-    if (session && !msg.content) {
-      if (!sessions[src]) {
-        sessions[src] = new Session(client, src, options);
+    if (msg.execSync) {
+      options.timeout = msg.execTimeout || syncExecTimeout;
+      let stdout, stderr;
+
+      try {
+        stdout = (0, _child_process.execSync)(cmd, options).toString();
+      } catch (e) {
+        stderr = e.stderr ? e.stderr.toString() : e.error;
       }
 
-      sessions[src].write(cmd);
+      return JSON.stringify({
+        stdout,
+        stderr
+      });
     } else {
-      (0, _child_process.exec)(cmd, options, async (error, stdout, stderr) => {
-        let res;
-
-        if (msg.content) {
-          // d-chat protocol
-          res = {
-            content: "```\n" + (stdout || stderr) + "\n```",
-            contentType: "text",
-            timestamp: new Date().toUTCString(),
-            isPrivate: true
-          };
-        } else {
-          res = {
-            stdout,
-            stderr
-          };
-        }
+      options.timeout = msg.execTimeout || asyncExecTimeout;
 
-        try {
-          await client.send(src, JSON.stringify(res), {
-            noReply: true
-          });
-        } catch (e) {
-          console.error("Send msg error:", e);
+      if (session && !msg.content) {
+        if (!sessions[src]) {
+          sessions[src] = new Session(client, src, options);
         }
-      });
+
+        sessions[src].write(cmd);
+      } else {
+        (0, _child_process.exec)(cmd, options, async (error, stdout, stderr) => {
+          let res;
+
+          if (msg.content) {
+            // d-chat protocol
+            res = {
+              content: "```\n" + (stdout || stderr) + "\n```",
+              contentType: "text",
+              timestamp: new Date().toUTCString(),
+              isPrivate: true
+            };
+          } else {
+            res = {
+              stdout,
+              stderr
+            };
+          }
+
+          try {
+            await client.send(src, JSON.stringify(res), {
+              noReply: true
+            });
+          } catch (e) {
+            console.error("Send msg error:", e);
+          }
+        });
+      }
     }
-  }
-});
\ No newline at end of file
+  });
+})();
\ No newline at end of file
diff --git a/package.json b/package.json
index 50f2948..f6adc0d 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "nkn-shell-daemon",
-  "version": "1.0.9",
+  "version": "1.1.0",
   "description": "NKN Shell Daemon",
   "main": "nshd.js",
   "bin": {
@@ -28,7 +28,7 @@
   },
   "homepage": "https://nkn.org",
   "dependencies": {
-    "nkn-sdk": "^1.1.6",
+    "nkn-sdk": "^1.1.7",
     "node-pty": "^0.9.0",
     "yargs": "^14.2.0"
   },
diff --git a/src/index.js b/src/index.js
index 72ab327..72e68d0 100644
--- a/src/index.js
+++ b/src/index.js
@@ -77,6 +77,7 @@ let argv = yargs
   .argv
 
 const isWindows = os.platform() === 'win32'
+const clientConnectTimeout = 20000
 const pingInterval = 20000
 const forcePingInterval = 60000
 const ptyCols = 120
@@ -205,12 +206,6 @@ function getAuthorizedUser(src) {
   return null
 }
 
-const client = new nkn.MultiClient({
-  originalClient: true,
-  seed: wallet.getSeed(),
-  identifier: identifier,
-})
-
 class Session {
   constructor(client, remoteAddr, options) {
     this.client = client
@@ -267,11 +262,9 @@ class Session {
   }
 }
 
-let sessions = {}
-
-client.onConnect(() => {
-  console.log('Listening at', client.addr)
+var sessions = {}
 
+function keepalive(client) {
   for (let c of Object.values(client.clients)) {
     setInterval(function () {
       try {
@@ -344,96 +337,129 @@ client.onConnect(() => {
       }, 3000);
     })
   }, forcePingInterval)
-})
+}
 
-client.onMessage(async ({ src, payload, payloadType, isEncrypted }) => {
-  if (!isEncrypted) {
-    console.log('Received unencrypted msg from', src)
-    return false
-  }
+(async () => {
+  let client
+  while (true) {
+    try {
+      client = new nkn.MultiClient({
+        originalClient: true,
+        seed: wallet.getSeed(),
+        identifier: identifier,
+      })
+    } catch (e) {
+      console.error('Create client error:', e);
+      continue
+    }
 
-  if (src.endsWith(client.getPublicKey()) && !payload) {
-    return
-  }
+    try {
+      await new Promise((resolve, reject) => {
+        client.onConnect(resolve)
+        setTimeout(reject, clientConnectTimeout);
+      })
+    } catch (e) {
+      console.error('Client connect timeout')
+      client.close().catch(console.error)
+      continue
+    }
 
-  let au = getAuthorizedUser(src)
-  if (!au) {
-    console.log('Received msg from unauthorized sender', src)
-    return false
+    break
   }
 
-  if (payloadType !== nkn.pb.payloads.PayloadType.TEXT) {
-    console.log('Received msg with wrong payload type from', src)
-    return false
-  }
+  console.log('Listening at', client.addr)
 
-  let msg = JSON.parse(payload)
+  keepalive(client)
 
-  if (msg.timestamp && (Date.now() - Date.parse(msg.timestamp)) > 60000) {
-    return false
-  }
+  client.onMessage(async ({ src, payload, payloadType, isEncrypted }) => {
+    if (!isEncrypted) {
+      console.log('Received unencrypted msg from', src)
+      return false
+    }
 
-  let options = {
-    uid: au.uid,
-    gid: au.gid,
-  }
+    if (src.endsWith(client.getPublicKey()) && !payload) {
+      return
+    }
 
-  if (session && msg.resize) {
-    if (!sessions[src]) {
-      sessions[src] = new Session(client, src, options)
+    let au = getAuthorizedUser(src)
+    if (!au) {
+      console.log('Received msg from unauthorized sender', src)
+      return false
     }
-    sessions[src].resize(msg.resize)
-    console.log('Resize to', msg.resize, 'from', src)
-  }
 
-  let cmd = msg.cmd || msg.content
-  if (!cmd) {
-    return false
-  }
+    if (payloadType !== nkn.pb.payloads.PayloadType.TEXT) {
+      console.log('Received msg with wrong payload type from', src)
+      return false
+    }
 
-  console.log('Execute cmd' + (logCmd ? ' ' + cmd : ''), 'from', src)
+    let msg = JSON.parse(payload)
 
-  if (msg.execSync) {
-    options.timeout = msg.execTimeout || syncExecTimeout
-    let stdout, stderr
-    try {
-      stdout = execSync(cmd, options).toString()
-    } catch (e) {
-      stderr = e.stderr ? e.stderr.toString() : e.error
+    if (msg.timestamp && (Date.now() - Date.parse(msg.timestamp)) > 60000) {
+      return false
     }
-    return JSON.stringify({
-      stdout,
-      stderr,
-    })
-  } else {
-    options.timeout = msg.execTimeout || asyncExecTimeout
-    if (session && !msg.content) {
+
+    let options = {
+      uid: au.uid,
+      gid: au.gid,
+    }
+
+    if (session && msg.resize) {
       if (!sessions[src]) {
         sessions[src] = new Session(client, src, options)
       }
-      sessions[src].write(cmd)
+      sessions[src].resize(msg.resize)
+      console.log('Resize to', msg.resize, 'from', src)
+    }
+
+    let cmd = msg.cmd || msg.content
+    if (!cmd) {
+      return false
+    }
+
+    console.log('Execute cmd' + (logCmd ? ' ' + cmd : ''), 'from', src)
+
+    if (msg.execSync) {
+      options.timeout = msg.execTimeout || syncExecTimeout
+      let stdout, stderr
+      try {
+        stdout = execSync(cmd, options).toString()
+      } catch (e) {
+        stderr = e.stderr ? e.stderr.toString() : e.error
+      }
+      return JSON.stringify({
+        stdout,
+        stderr,
+      })
     } else {
-      exec(cmd, options, async (error, stdout, stderr) => {
-        let res;
-        if (msg.content) { // d-chat protocol
-          res = {
-            content: "```\n" + (stdout || stderr) + "\n```",
-            contentType: "text",
-            timestamp: new Date().toUTCString(),
-            isPrivate: true,
+      options.timeout = msg.execTimeout || asyncExecTimeout
+      if (session && !msg.content) {
+        if (!sessions[src]) {
+          sessions[src] = new Session(client, src, options)
+        }
+        sessions[src].write(cmd)
+      } else {
+        exec(cmd, options, async (error, stdout, stderr) => {
+          let res;
+          if (msg.content) { // d-chat protocol
+            res = {
+              content: "```\n" + (stdout || stderr) + "\n```",
+              contentType: "text",
+              timestamp: new Date().toUTCString(),
+              isPrivate: true,
+            }
+          } else {
+            res = {
+              stdout,
+              stderr,
+            }
           }
-        } else {
-          res = {
-            stdout,
-            stderr,
+          try {
+            await client.send(src, JSON.stringify(res), { noReply: true })
+          } catch (e) {
+            console.error("Send msg error:", e)
           }
-        }
-        try {
-          await client.send(src, JSON.stringify(res), { noReply: true })
-        } catch (e) {
-          console.error("Send msg error:", e)
-        }
-      });
+        });
+      }
     }
-  }
-})
+  })
+})()
diff --git a/yarn.lock b/yarn.lock
index 489e035..f736d5e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1875,10 +1875,10 @@ needle@^2.2.1:
     iconv-lite "^0.4.4"
     sax "^1.2.4"
 
-nkn-sdk@^1.1.6:
-  version "1.1.6"
-  resolved "https://registry.yarnpkg.com/nkn-sdk/-/nkn-sdk-1.1.6.tgz#2735c8217df080175bf3fdca3c8fda2594828b97"
-  integrity sha512-LYiUZCWFite5hRlVSShOiZUTcvIt6O+YXT0XddHhuJqESh6YFaXR9Gs7tsr70JXp8GX8Us+/CVTyomIs0p+z1Q==
+nkn-sdk@^1.1.7:
+  version "1.1.7"
+  resolved "https://registry.yarnpkg.com/nkn-sdk/-/nkn-sdk-1.1.7.tgz#866c85f54212ec0a2a41d6ff48c24a241ef619b2"
+  integrity sha512-1hoqtk+uopfA6KdVX7jCsMLzj3Tz/U1d25OpK/iIqnEWprPrZOL5b/AKzfomp7sf1DBBmwT12uFI0BBK9yU2xw==
   dependencies:
     "@nkn/ncp" "^1.0.6"
     axios "^0.19.2"