题目：
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
2.配置ssh免密登陆，能够通过客户端主机通过redhat用户和服务端主机基于公钥验证方式进行远程连接
一、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
服务器端 IP 192.168.101.112/24 主机名 [root@Rhce~]
客 户 端 IP 192.168.101.152/24 主机名 [root@localhost ~]
前置操作首先保证时区一致
[root@Rhce ~]# timedatectl 使用该命令查看 保证时区和ntp service 都是active状态
systemctl stop firewalld 防火墙关闭
setenforce 0 关闭selinux服务器配置：
[root@Rhce~]# vim /etc/chrony.conf 对其配置文件进行编辑
修改如下内容
#pool 2.rhel.pool.ntp.org iburst 服务器端不需要向上层同步时间
allow 192.168.101.0/24 允许客户端向本服务器同步时间
local stratum 10 定义本地主机时间服务器在第10层级 15以内保证偏差在1-50ms
[root@Rhce ~]# systemctl restart chronyd 重启软件以加载配置客户端配置：
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[root@localhost ~]# vim /etc/chrony.conf
修改如下内容
pool 192.168.101.112 iburst 从该服务器处同步时间
[root@localhost ~]# systemctl restart chronyd 重启chronyd 服务测试：
[root@Rhce ~]# date
Sat Apr 8 16:35:00 CST 2023
[root@localhost ~]# date
Sat Apr 8 16:35:16 CST 2023 保持一致
服务器修改时间 检查客户机
[root@Rhce ~]# date 111110102023.20
Fri Nov 11 10:10:20 CST 2023
[root@Rhce ~]# systemctl restart chronyd
[root@localhost ~]# date
Fri Nov 11 10:10:20 CST 2023二、配置ssh免密登陆，能够通过客户端主机通过redhat用户和服务端主机基于公钥验证方式进行远程连接。
创建新用户：
[root@node1 ~]# useradd t1
[root@npde1 ~]# passwd t1
更改用户 t1 的密码 。
新的密码：
无效的密码： 密码少于 8 个字符
重新输入新的密码：
passwd：所有的身份验证令牌已经成功更新。创建新的密钥对，并且发送到指定目录：
[t1@node1 root]$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/redhat/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/redhat/.ssh/id_rsa
Your public key has been saved in /home/redhat/.ssh/id_rsa.pub
The key fingerprint is:
SHA256:peN3IXp4nusrQ5Ca/umHNzX6fO6SPJSSf6LCnv2mNc8 redhat@node1
The key's randomart image is:
+---[RSA 3072]----+
| |
| |
| . . |
| o o |
| o .S.... |
| o .++=. . |
| . . o+B*o. |
| . ++BBO*o |
| +*++@X@E |
+----[SHA256]-----+
[t1@node1 root]$
[t1@node1 root]$ ssh-copy-id [email protected]
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/home/redhat/.ssh/id_rsa.pub"
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
[email protected]'s password:
Number of key(s) added: 1
Now try logging into the machine, with: "ssh '[email protected]'"
and check to make sure that only the key(s) you wanted were added.客户端测试：
[t1@node1 root]$ ssh [email protected]
Activate the web console with: systemctl enable --now cockpit.socket
Register this system with Red Hat Insights: insights-client --register
Create an account or view all your systems at https://red.ht/insights-dashboard
Last login: Sat Mar 18 19:58:18 2023 from 192.168.101.125
[root@server ~]# 切换完成