diff --git a/channel.py b/channel.py
index be95c44..a51f24c 100644
--- a/channel.py
+++ b/channel.py
@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import json
 import logging
 import webapp2
 
@@ -29,7 +30,11 @@ class OnChannelConnect(webapp2.RequestHandler):
     instance_id = self.request.get('from')
     instance = models.Instance.FromID(instance_id)
     if not instance:
-      logging.error('Channel opened with invalid instance_id: %s', instance_id)
+      logging.warning('Channel opened with invalid instance_id: %s', instance_id)
+      message = {
+        'event_type': 'close',
+      }
+      channel.send_message(instance_id, json.dumps(msg, default=utils.EncodeJSON))
       return
     instance.active = True
     instance.put()
diff --git a/static/cosmopolite.js b/static/cosmopolite.js
index 8a21402..8955684 100644
--- a/static/cosmopolite.js
+++ b/static/cosmopolite.js
@@ -422,7 +422,11 @@ Cosmopolite.prototype.unpin = function(id) {
  * @private
  */
 Cosmopolite.prototype.loggingPrefix_ = function() {
-  return 'cosmopolite (' + this.namespace_ + '):';
+  if (this.instanceID_) {
+    return 'cosmopolite (' + this.namespace_ + ' / ' + this.instanceID_ + '):';
+  } else {
+    return 'cosmopolite (' + this.namespace_ + '):';
+  }
 };
 
 /**
@@ -605,7 +609,7 @@ Cosmopolite.prototype.sendRPCs_ = function(commands, delay) {
     return;
   }
   var request = {
-    'instance_id': this.instanceId_,
+    'instance_id': this.instanceID_,
     'commands': [],
   };
   commands.forEach(function(command) {
@@ -786,7 +790,7 @@ Cosmopolite.prototype.createChannel_ = function() {
   }
 
   /** @type {string} */
-  this.instanceId_ = this.uuid_();
+  this.instanceID_ = this.uuid_();
 
   var rpcs = [
     {
@@ -899,6 +903,18 @@ Cosmopolite.prototype.onSocketError_ = function(msg) {
   }
 };
 
+/**
+ * Callback on receiving a 'close' event from the server
+ *
+ * @private
+ */
+Cosmopolite.prototype.onClose_ = function() {
+  console.log(this.loggingPrefix_(), 'server asked us to close our socket');
+  if (this.socket_) {
+    this.socket_.close();
+  }
+};
+
 /**
  * Callback on receiving a 'login' event from the server
  *
@@ -1060,6 +1076,9 @@ Cosmopolite.prototype.onServerEvent_ = function(e) {
     this.profilePromises_ = [];
   }
   switch (e['event_type']) {
+    case 'close':
+      this.onClose_();
+      break;
     case 'login':
       this.onLogin_(/** @type {typeLogin} */ (e));
       break;