时区设置-蒲公英云

时区设置

时区设置 Linux 运维以及脚本干货: 欢迎分享，欢迎folk, 欢迎留言
https://unnunique.github.io/AADocs/skill-docs/linux/
https://github.com/unnunique/unnunique.github.io/blob/master/AADocs/skill-docs/linux/index.md

时区理解

其实初中地理课已经涉及，很多人都多少了解一些，可能只是细节搞不太清楚。为什么会将地球分为不同时区呢？
因为地球总是自西向东自转，东边总比西边先看到太阳，东边的时间也总比西边的早。东边时刻与西边时刻的差值不仅要以时计，
而且还要以分和秒来计算。整个地球分为二十四时区，每个时区都有自己的本地时间。在国际无线电通信场合，为了统一起见，
使用一个统一的时间，称为通用协调时(UTC, Universal Time Coordinated)。(GMT, Greenwich Mean Time)一样，都与英国伦敦的本地时相同。

查看时区

Date -R 或者， more /etc/sysconfig/clock

root@hello:/home # date -R
Fri, 13 Jan 2017 15:11:12 +0800

root@hello:/home # more /etc/sysconfig/clock

Path: System/Environment/Clock
Description: Information about your timezone and time
Type: string(-u,—utc,—localtime)
ServiceRestart: boot.clock
Command: /sbin/refresh_initrd
#

Set to “-u” if your system clock is set to UTC, and to “—localtime”
if your clock runs that way.
#
HWCLOCK=”-u”

Type: yesno
Default: yes
Description: Write back system time to the hardware clock
#

Is set to “yes” write back the system time to the hardware
clock at reboot or shutdown. Usefull if hardware clock is
much more inaccurate than system clock. Set to “no” if
system time does it wrong due e.g. missed timer interrupts.
If set to “no” the hardware clock adjust feature is also
skipped because it is rather useless without writing back
the system time to the hardware clock.
#
SYSTOHC=”yes”

Type: string(Europe/Berlin,Europe/London,Europe/Paris)
ServiceRestart: boot.clock
#

Timezone (e.g. CET)
(this will set /usr/lib/zoneinfo/localtime)
#
TIMEZONE=”Asia/Shanghai”
DEFAULT_TIMEZONE=”US/Eastern”

修改时区,3种方法，

1,tzselect, 设置环境变量，export TZ=’Asia/Shanghai’ ,source /etc/profile.
2,cp /usr/share/zoneinfo/America/Los_Angeles /etc/localtime
3,ln /usr/share/zoneinfo/Asia/Shanghai /etc/localtime ，报错的话，rm /etc/localtime,
之后 ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
4，如果是，Rehat 或者centOS 可以用timeconfig 设置。