ssh connection to host port 22 connection refused - hadoop

Question

I use a VMware virtualization system. I have centos release 7 as my operating system. I installed hadoop2.7.1. After installing Hadoop I ran the command :#hdfs namenode -format, it ran successfully. But when I run the command :#./start-all.sh it gives me errors. I tried several proposals that I saw on the internet but the problem persists
[root#MASTER sbin]# ./start-all.sh
This script is Deprecated. Instead use start-dfs.sh and start-yarn.sh
21/06/17 19:06:27 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Starting namenodes on [MASTER]
root#master's password:
MASTER: starting namenode, logging to /usr/local/hadoop/logs/hadoop-root-namenode-MASTER.out
localhost: ssh: connect to host localhost port 22: Connection refused
Starting secondary namenodes [0.0.0.0]
0.0.0.0: ssh: connect to host 0.0.0.0 port 22: Connection refused
21/06/17 19:06:49 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
starting yarn daemons
starting resourcemanager, logging to /usr/local/hadoop/logs/yarn-root-resourcemanager-MASTER.out
localhost: ssh: connect to host localhost port 22: Connection refused

Answer 1

Provide ssh-key less access to all your worker nodes in hosts file, even localhost. Read instruction in the Tutorial of How To Set Up SSH Keys on CentOS 7.
At last test access without password by ssh localhost and ssh [yourworkernode].
Also, run start-dfs.sh and if was successful run start-yarn.sh.