[autoscaler] uptime redirect fix (#5907)

* small change

* comment

Author: richardliaw

python/ray/autoscaler/updater.py

@@ -403,11 +403,11 @@ def wait_ready(self, deadline):
                     logger.debug(self.log_prefix +
                                  "Waiting for remote shell...")
 
-                    # Setting redirect=False allows the user to see errors like
+                    # Setting redirect=None allows the user to see errors like
                     # unix_listener: path "/tmp/rkn_ray_ssh_sockets/..." too
                     # long for Unix domain socket.
-                    self.cmd_runner.run("uptime", timeout=5, redirect=False)
-
+                    self.cmd_runner.run("uptime", timeout=5, redirect=None)
+                    logger.debug("Uptime succeeded.")
                     return True
 
                 except Exception as e:
@@ -429,6 +429,7 @@ def do_update(self):
         self.wait_ready(deadline)
 
         node_tags = self.provider.node_tags(self.node_id)
+        logger.debug("Node tags: {}".format(str(node_tags)))
         if node_tags.get(TAG_RAY_RUNTIME_CONFIG) == self.runtime_hash:
             logger.info(self.log_prefix +
                         "{} already up-to-date, skip to ray start".format(