在安装cloudera CDH5.8时，从节点安装成功，但master无法完成安装，显示：
Cloudera can not receive the detection signal from the Agent during installation • Make sure that the host name is configured correctly. • Make sure that port 7182 is accessible on the Cloudera Manager Server (check the firewall rules). • Make sure that ports 9000 and 9001 are idle on the host being added. • Check the proxy log in /var/log/cloudera-scm-agent/ on the host that is being added (some logs can be found in the installation details). 但是我closures了防火墙，7182/9000/9001端口不被占用。
然后我打开日志文件：cloudera-scm-agent.log我发现：
[14/Aug/2017 09:54:10 +0000] 9294 MainThread agent INFO To override these variables, use /etc/cloudera-scm-agent/config.ini. Environment variables for CDH locations are not used when CDH is installed from parcels. [14/Aug/2017 09:54:10 +0000] 9294 MainThread agent INFO Re-using pre-existing directory: /var/run/cloudera-scm-agent/process [14/Aug/2017 09:54:10 +0000] 9294 MainThread agent INFO Re-using pre-existing directory: /var/run/cloudera-scm-agent/supervisor [14/Aug/2017 09:54:10 +0000] 9294 MainThread agent INFO Re-using pre-existing directory: /var/run/cloudera-scm-agent/flood [14/Aug/2017 09:54:10 +0000] 9294 MainThread agent INFO Re-using pre-existing directory: /var/run/cloudera-scm-agent/supervisor/include [14/Aug/2017 09:54:10 +0000] 9294 MainThread agent ERROR Failed to connect to previous supervisor. Traceback (most recent call last): File "/usr/lib64/cmf/agent/build/env/lib/python2.6/site-packages/cmf-5.8.0-py2.6.egg/cmf/agent.py", line 2039, in find_or_start_supervisor self.get_supervisor_process_info() File "/usr/lib64/cmf/agent/build/env/lib/python2.6/site-packages/cmf-5.8.0-py2.6.egg/cmf/agent.py", line 2185, in get_supervisor_process_info self.identifier = self.supervisor_client.supervisor.getIdentification() File "/usr/lib64/python2.6/xmlrpclib.py", line 1199, in __call__ return self.__send(self.__name, args) File "/usr/lib64/python2.6/xmlrpclib.py", line 1489, in __request verbose=self.__verbose File "/usr/lib64/cmf/agent/build/env/lib/python2.6/site-packages/supervisor-3.0-py2.6.egg/supervisor/xmlrpc.py", line 470, in request '' ) ProtocolError: <ProtocolError for 127.0.0.1/RPC2: 401 Unauthorized> [14/Aug/2017 09:54:10 +0000] 9294 MainThread tmpfs INFO Reusing mounted tmpfs at /var/run/cloudera-scm-agent/process [14/Aug/2017 09:54:12 +0000] 9294 MainThread agent INFO Trying to connect to newly launched supervisor (Attempt 1) [14/Aug/2017 09:54:12 +0000] 9294 MainThread agent ERROR Failed! trying again in 1 second(s)