[root@localhost ~]# rpm -ivh mailx-12.5-43.fc38.x86_64.rpm 
warning: mailx-12.5-43.fc38.x86_64.rpm: Header V4 RSA/SHA256 Signature, key ID 18b8e74c: NOKEY
Verifying...                          ################################# [100%]
Preparing...                          ################################# [100%]
Updating / installing...
   1:mailx-12.5-43.fc38               ################################# [100%]

tail /etc/mail.rc
 
# For Linux and BSD, this should be set.
set bsdcompat
 
######################################################################
set from=m137****8953@163.com   #设置发件人邮箱地址
set smtp=smtp.163.com   #指定 SMTP 服务器地址，网易163邮箱的SMTP服务器是 smtp.163.com
set smtp-auth-user=m137****8953@163.com   #设置 SMTP 认证的用户名，通常与发件人邮箱一致
set smtp-auth-password=KPNJWJL******FVF   #设置 SMTP 认证密码（授权码）
set smtp-auth=login   #指定 SMTP 认证方式，login 表示使用用户名+密码认证（网易邮箱支持此方式）

[root@localhost ~]# crontab -e
no crontab for root - using an empty one
crontab: installing new crontab
 
0 9 * * * echo "I'm the best." | mailx -s "开启元气满满的一天！" m137****8953@163.com
 

[root@localhost ~]# crontab -l
0 9 * * * echo "I'm the best." | mailx -s "开启元气满满的一天！" m137****8953@163.com

yum install chrony -y

[root@localhost ~]# vim /etc/chrony.conf
 
# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (https://www.pool.ntp.org/join.html).
#pool 2.rhel.pool.ntp.org iburst   #将行注释，作为时间服务器，不需要再向其他服务器同步时间
 
# Use NTP servers from DHCP.
sourcedir /run/chrony-dhcp
 
# Record the rate at which the system clock gains/losses time.
driftfile /var/lib/chrony/drift
 
# Allow the system clock to be stepped in the first three updates
# if its offset is larger than 1 second.
makestep 1.0 3
 
# Enable kernel synchronization of the real-time clock (RTC).
rtcsync
 
# Enable hardware timestamping on all interfaces that support it.
#hwtimestamp *
 
# Increase the minimum number of selectable sources required to adjust
# the system clock.
#minsources 2
 
# Allow NTP client access from local network.
allow 192.168.233.0/24  #此行注释放通，定义允许向该服务器发起时间同步的ip网段
 
# Serve time even if not synchronized to a time source.
local stratum 10  #将此行注释放通，定义时间服务器层级，默认第10层
 

[root@localhost ~]# systemctl restart chronyd

[root@localhost ~]# systemctl stop firewalld.service 
[root@localhost ~]# setenforce 0

[root@localhost ~]# vim /etc/chrony.conf
 
# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (https://www.pool.ntp.org/join.html).
pool 192.168.233.130 iburst  #将此行的地址更改为服务端ip地址
 
 
[root@localhost ~]# systemctl restart chronyd

date 123115302023.30
 
[root@localhost ~]# date
Sun Dec 31 03:31:03 PM CST 2023

[root@localhost ~]# systemctl restart chronyd
[root@localhost ~]# date
Thu Apr 24 04:06:49 PM CST 2025