date displays the current time
basic syntax
1) date （功能描述：显示当前时间）
2) date +%Y （功能描述：显示当前年份）
3) date +%m （功能描述：显示当前月份）
4) date +%d （功能描述：显示当前是哪一天）
5) date "+%Y-%m-%d %H:%M:%S"（功能描述：使用特定格式显示年月日时分秒）
Manually set the system time as follows
date -s "string time" For example:
date -s "2020-11-11 11:22:22"
cal View the calendar View the calendar of the
specified year
Time synchronization
Students who often use Linux know that Linux time cannot be synchronized with the internet by default, so you need to perform the following operations:
- Execute yum install ntpdate to download the Linux time synchronization service software (downloaded here)
Note: If you are using a version below centos7.0, from December 2, 2020, Netease, Ali, Tsinghua and other mirrors will not provide update maintenance. It just can't be used. Change or read another blog post
https://blog.csdn.net/qq_43674360/article/details/111300657
Set the current time
System hardware time synchronization
Set the timing task of time synchronization
because root privileges are required, so it is recommended to log in and execute as root user The following command:
Check whether the boot is enabled,
execute crontab -e
* */1 * * * ntpdate ntp.api.bz; hwclock -w(synchronize the virtual machine time and hardware time every hour)
Restart crond
ok
Attachment:
If the above ntpdate ntp.api.bz server cannot be synchronized, you can try the following time servers:
0.# ntpdate time.nist.gov
1.# ntpdate time.nuri.net
2.# ntpdate asia.pool. ntp.org
3.# ntpdate ntp.api.bz
hope to help you! ! !