The problem that the port 50070 of the Hadoop service cannot be accessed

hadoop of NameNode, DataNode, ResourceManager, NodeManager have been started, you can remote server, you can hdfs dfs /access hdfs, but the browser is not open port 50070
with netstat -antdiscovery 8020 and 50070 can only local access

I have found a lot of information. It is said that fs.defaultFS is configured as hdfs://0.0.0.0:8020 in the core-site.xml configuration. In fact, this has no effect.

Later, I finally hostname -ifound that the local ip address has 127.0.0.1

Comment out the line 127.0.0.1 in /etc/hosts and change it to the real ip