我正在尝试使用命令“start-dfs.sh”启动我的 hadoop 集群，但出现如下错误
在 [master] 上启动名称节点
master: ssh: connect to host master port 22: Connection refused
启动数据节点
master: ssh: connect to host master port 22: Connection refused
我检查了 ssh 状态，然后它返回给我：
ssh.service - OpenBSD Secure Shell server
Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enab
Active: failed (Result: start-limit-hit) since Tue 2020-02-04 14:15:01 +04; 2
Process: 5017 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=255)
Feb 04 14:15:00 hadoop-HP-Pro3500-Series systemd[1]: ssh.service: Unit entered f
Feb 04 14:15:00 hadoop-HP-Pro3500-Series systemd[1]: ssh.service: Failed with re
Feb 04 14:15:01 hadoop-HP-Pro3500-Series systemd[1]: ssh.service: Service hold-o
Feb 04 14:15:01 hadoop-HP-Pro3500-Series systemd[1]: Stopped OpenBSD Secure Shel
Feb 04 14:15:01 hadoop-HP-Pro3500-Series systemd[1]: ssh.service: Start request
Feb 04 14:15:01 hadoop-HP-Pro3500-Series systemd[1]: Failed to start OpenBSD Sec
Feb 04 14:15:01 hadoop-HP-Pro3500-Series systemd[1]: ssh.service: Unit entered f
如何解决这个问题？