一、同步阿里云服务器时间
服务端设置
1.检查chrony服务是否安装，设置chrony开机自启，查看chrony服务状态
[root@node1-server ~]# rpm -q chrony # rpm -q 用于查看包是否安装
chrony-4.3-1.el9.x86_64
[root@node1-server ~]# systemctl enable --now chronyd # 设置服务开机自启
[root@node1-server ~]# systemctl status chronyd # 查看chronyd服务状态
● chronyd.service - NTP client/server
Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled; preset: enabled)
Active: active (running) since Tue 2025-03-25 14:11:34 CST; 2h 22min ago
Docs: man:chronyd(8)
man:chrony.conf(5)
Main PID: 905 (chronyd)
Tasks: 1 (limit: 10681)
Memory: 4.0M
CPU: 80ms
CGroup: /system.slice/chronyd.service
└─905 /usr/sbin/chronyd -F 2
2.关闭防火墙，SELinux设置为宽容模式，查看防火墙状态
[root@node1-server ~]# systemctl stop firewalld && systemctl disable firewalld # 关闭防火墙服务，关闭成功后禁用服务
Removed "/etc/systemd/system/multi-user.target.wants/firewalld.service".
Removed "/etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service".
[root@node1-server ~]# setenforce 0 # SELinux 调整为宽容模式
[root@node1-server ~]# getenforce # 查看 SELinux 状态
Permissive # 宽容模式
[root@node1-server ~]# systemctl status firewalld.service # 查看防火墙状态
○ firewalld.service - firewalld - dynamic firewall daemon
Loaded: loaded (/usr/lib/systemd/system/firewalld.service; disabled; preset: enabled)
Active: inactive (dead)
Docs: man:firewalld(1)
3.编辑服务端/etc/chrony.conf文件
[root@node1-server ~]# vim /etc/chrony.conf
3 #pool 2.rhel.pool.ntp.org iburst # 注释此行
4 pool ntp.aliyun.com iburst # pool 是一个关键字，作用是指定一组 NTP 服务器，iburst表示的是首次同步的时候快速同步
27 #allow 192.168.0.0/16 # 注释此行
28 allow 192.168.11.0/24 # 允许同步该网段
4.重启服务，查看服务，查看日期
[root@node1-server ~]# systemctl restart chronyd # 重启服务
[root@node1-server ~]# chronyc sources -v # 查看服务
.-- 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 25 +20ms[ +30ms] +/- 72ms
[root@node1-server ~]# date # 查看日期
Tue Mar 25 04:54:42 PM CST 2025 # 与阿里云服务器同步成功
客户端设置
1.关闭防火墙并查看防火墙状态
[root@node2-client ~]# systemctl stop firewalld.service && systemctl disable firewalld.service #关闭防火墙
Removed "/etc/systemd/system/multi-user.target.wants/firewalld.service".
Removed "/etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service".
[root@node2-client ~]# systemctl status firewalld.service #查看防火墙状态
○ firewalld.service - firewalld - dynamic firewall daemon
Loaded: loaded (/usr/lib/systemd/system/firewalld.service; disabled; preset: enabled)
Active: inactive (dead)
Docs: man:firewalld(1)
2.编辑客户端配置文件
[root@node2-client ~]# vim /etc/chrony.conf
3 #pool 2.rhel.pool.ntp.org iburst
4 pool 192.168.11.135 iburst # 以192.168.11.135为时间服务器
3.客户端重启服务，查看服务，查看日期
[root@node2-client ~]# systemctl restart chronyd # 重启服务
[root@node2-client ~]# chronyc sources -v # 查看服务
.-- 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
=========================================================================
^* 192.168.11.135 3 6 17 8 +30us[ +80us] +/- 54ms
[root@node2-client ~]# date # 查看日期
Tue Mar 25 04:59:27 PM CST 2025 #与服务端同步成功
二、同步本地服务器时间
服务端配置
1.修改服务端配置文件
[root@node1-server ~]# vim /etc/chrony.conf
30 # Serve time even if not synchronized to a time source.
31 local stratum 10 # 把本地系统设置为一个 NTP 时间源，并且将其 Stratum 层级设定为 10
2.修改 /etc/resolv.conf 文件，不使用dns解析，模拟无法上网的情况
[root@node1-server ~]# vim /etc/resolv.conf
# Generated by NetworkManager
#nameserver 223.5.5.5 # 注释此行
3.修改错误时间
[root@node1-server ~]# date -s '2021-12-13 14:54:58' # 修改时间是为了让结果更明显
Mon Dec 13 02:54:58 PM CST 2021
4.重启服务，查看服务，查看日期
[root@node1-server ~]# systemctl restart chronyd
[root@node1-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
=========================================================================
[root@node1-server ~]# # 此处能看到没有时间服务器与本机同步
[root@node1-server ~]# date
Mon Dec 13 02:56:42 PM CST 2021
客户端配置
仅需客户端重启服务，查看服务，查看日期
[root@node2-client ~]# systemctl restart chronyd
[root@node2-client ~]# 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
=========================================================================
^* 192.168.11.135 10 6 17 8 +7530ns[+8920ns] +/- 150us
[root@node2-client ~]# date
Mon Dec 13 02:58:41 PM CST 2021 # 时间与服务端同步成功
