1：配置ntp时间服务器，确保客户端主机能和服务主机同步时间
第一步，将服务器的时间同步对象改为阿里的时间服务器（这样比较精准）
先启动服务：[root@server ~]# systemctl start chronyd
进入配置文件：[root@server ~]# vim /etc/chrony.conf
然后将同步对象改为阿里的服务器
第二步骤：在服务器中，将客户端设置为白名单
然后重启服务：[root@server ~]# systemctl restart chronyd
查看是否同步成功
[root@server ~]# chronyc sources -v
.-- Source mode '^' = server, '=' = peer, '#' = local clock.
/ .- Source state '*' = current best, '+' = combined, '-' = not combined,
| / 'x' = may be in error, '~' = too variable, '?' = unusable.
|| .- xxxx [ yyyy ] +/- zzzz
|| Reachability register (octal) -. | xxxx = adjusted offset,
|| Log2(Polling interval) --. | | yyyy = measured offset,
|| \ | | zzzz = estimated error.
|| | | \
MS Name/IP address Stratum Poll Reach LastRx Last sample
===============================================================================
^* 203.107.6.88 2 6 17 26 +367us[+3046us] +/- 37ms最后在客户端上修改同步对象
然后重启服务再查看
2：配置ssh免密登录，能够实现客户端主机通过服务器端的redhat账户进行基于公钥验证的远程登录
首先创建redhat用户
[root@server ~]# adduser redhat
[root@server ~]# passwd redhat
然后进入客户端创建公钥
[root@wang ~]# ssh-keygen -t rsa
过程一路回车发送公钥
[root@wang ~]# ssh-copy-id redhat@192.168.153.137
输入redhat的密码最后验证
[root@wang ~]# ssh redhat@192.168.153.137
Authorized users only. All activities may be monitored and reported.
Authorized users only. All activities may be monitored and reported.
Last login: Wed Jan 24 18:48:05 2024 from 192.168.153.130
Welcome to 5.10.0-182.0.0.95.oe2203sp3.x86_64System information as of time: 2024年 01月 24日 星期三 18:53:07 CST
System load: 0.00
Processes: 147
Memory used: 11.7%
Swap used: 0%
Usage On: 7%
IP address: 192.168.153.141
Users online: 4
To run a command as administrator(user "root"),use "sudo <command>".
[redhat@server ~]$
