无法启动Namenode、二级Namenode和Datanode

Question

我已经将Hadoop-2.7.3安装在VirtualBox上。

当我在终端中输入命令./start-all.sh时，Namenode、Secondary Namenode和Datanode没有启动。下面是错误截图。请对这个问题提出一些解决办法。

在我的终端窗口上出现错误。

sreenu@MyPC:~/hdfs/sbin$ ./start-all.sh

This script is Deprecated. Instead use start-dfs.sh and start-yarn.sh
17/07/24 16:38:12 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable

Starting namenodes on [localhost]
localhost: ssh: connect to host localhost port 22: Connection refused
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

17/07/24 16:38:19 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable

starting yarn daemons
resourcemanager running as process 2899. Stop it first.

localhost: ssh: connect to host localhost port 22: Connection refused

sreenu@MyPC:~/hdfs/sbin$ jps
3536 Jps
2899 ResourceManager
3175 JobHistoryServer

sreenu@MyPC:~/hdfs/sbin$ 

我在终端窗口看到了错误。

Answer 1

此问题已通过卸载和重新安装openssh服务器和openssh客户机在我的计算机上得到解决。

命令：

sudo apt-获取删除openssh-server openssh-client

sudo apt安装openssh-server openssh-client

关闭终端，重新启动VirtualBox并再次启动所有守护进程。

Answer 2

安装ssh之后，您需要实际启动ssh服务器。设置的问题是ssh服务器没有运行。要验证此问题，请运行：

$ ssh localhost

如果得到相同的错误，即localhost: ssh: connect to host localhost port 22: Connection refused，那么使用以下命令启动ssh服务：

$ /etc/init.d/ssh start

如果您没有从ssh localhost中得到任何错误，那么还有其他一些问题。