服务器时钟同步和数据库时间设置

1.离线设置集群时钟同步

服务器环境：ubuntu 18.04

1.1安装ntp

下载ntp包：
链接：https://pan.baidu.com/s/19jQmhvhuDrpuiN0zOlZw-Q?pwd=ojrt
解压位置：/var/cache/apt/archives
sudo apt-get install ntp （可以跳过）
dpkg -i /var/cache/apt/archives/*.deb
修改配置文件：(依据具体情况修改ip)
服务器端（192.168.137.13）：

# /etc/ntp.conf, configuration for ntpd; see ntp.conf(5) for help

driftfile /var/lib/ntp/ntp.drift

# Leap seconds definition provided by tzdata
leapfile /usr/share/zoneinfo/leap-seconds.list

# Enable this if you want statistics to be logged.
#statsdir /var/log/ntpstats/

statistics loopstats peerstats clockstats
filegen loopstats file loopstats type day enable
filegen peerstats file peerstats type day enable
filegen clockstats file clockstats type day enable

# Specify one or more NTP servers.

# Use servers from the NTP Pool Project. Approved by Ubuntu Technical Board
# on 2011-02-08 (LP: #104525). See http://www.pool.ntp.org/join.html for
# more information.
#pool 0.ubuntu.pool.ntp.org iburst
#pool 1.ubuntu.pool.ntp.org iburst
#pool 2.ubuntu.pool.ntp.org iburst
#pool 3.ubuntu.pool.ntp.org iburst
server 0.cn.pool.ntp.org
server 1.cn.pool.ntp.org
server 2.cn.pool.ntp.org
server 3.cn.pool.ntp.org

# 允许上层时间服务器主动修改本机时间
restrict 0.cn.pool.ntp.org nomodify notrap noquery
restrict 1.cn.pool.ntp.org nomodify notrap noquery
restrict 2.cn.pool.ntp.org nomodify notrap noquery
restrict 3.cn.pool.ntp.org nomodify notrap noquery
# Use Ubuntu's ntp server as a fallback.
#pool ntp.ubuntu.com
# 外部时间服务器不可用时，以本地时间作为时间服务
server 127.127.1.0
fudge 127.127.1.0 stratum 10
# Access control configuration; see /usr/share/doc/ntp-doc/html/accopt.html for
# details.  The web page <http://support.ntp.org/bin/view/Support/AccessRestrictions>
# might also be helpful.
#
# Note that "restrict" applies to both servers and clients, so a configuration
# that might be intended to block requests from certain clients could also end
# up blocking replies from your own upstream servers.

# By default, exchange time with everybody, but don't allow configuration.
restrict -4 default kod notrap nomodify nopeer noquery limited
restrict -6 default kod notrap nomodify nopeer noquery limited

# Local users may interrogate the ntp server more closely.
restrict 127.0.0.1
restrict ::1

# Needed for adding pool entries
restrict source notrap nomodify noquery

# Clients from this (example!) subnet have unlimited access, but only if
# cryptographically authenticated.
#restrict 192.168.10.245  mask 255.255.0.0 notrust
restrict 192.168.10.245 mask 255.255.0.0

# If you want to provide time to your local subnet, change the next line.
# (Again, the address is an example only.)
#broadcast 192.168.123.255

# If you want to listen to time broadcasts on your local subnet, de-comment the
# next lines.  Please do this only if you trust everybody on the network!
#disable auth
#broadcastclient

#Changes recquired to use pps synchonisation as explained in documentation:
#http://www.ntp.org/ntpfaq/NTP-s-config-adv.htm#AEN3918

#server 127.127.8.1 mode 135 prefer    # Meinberg GPS167 with PPS
#fudge 127.127.8.1 time1 0.0042        # relative to PPS for my hardware

#server 127.127.22.1                   # ATOM(PPS)
#fudge 127.127.22.1 flag3 1            # enable PPS API

客户端：

# /etc/ntp.conf, configuration for ntpd; see ntp.conf(5) for help

driftfile /var/lib/ntp/ntp.drift

# Leap seconds definition provided by tzdata
leapfile /usr/share/zoneinfo/leap-seconds.list

# Enable this if you want statistics to be logged.
#statsdir /var/log/ntpstats/

statistics loopstats peerstats clockstats
filegen loopstats file loopstats type day enable
filegen peerstats file peerstats type day enable
filegen clockstats file clockstats type day enable

# Specify one or more NTP servers.

# Use servers from the NTP Pool Project. Approved by Ubuntu Technical Board
# on 2011-02-08 (LP: #104525). See http://www.pool.ntp.org/join.html for
# more information.
#pool 0.ubuntu.pool.ntp.org iburst
#pool 1.ubuntu.pool.ntp.org iburst
#pool 2.ubuntu.pool.ntp.org iburst
#pool 3.ubuntu.pool.ntp.org iburst
server 192.168.137.13
restrict 192.168.137.13 nomodify notrap noquery


server 127.127.1.0
fudge 127.127.1.0 stratum 10
# Use Ubuntu's ntp server as a fallback.
#pool ntp.ubuntu.com

# Access control configuration; see /usr/share/doc/ntp-doc/html/accopt.html for
# details.  The web page <http://support.ntp.org/bin/view/Support/AccessRestrictions>
# might also be helpful.
#
# Note that "restrict" applies to both servers and clients, so a configuration
# that might be intended to block requests from certain clients could also end
# up blocking replies from your own upstream servers.

# By default, exchange time with everybody, but don't allow configuration.
restrict -4 default kod notrap nomodify nopeer noquery limited
restrict -6 default kod notrap nomodify nopeer noquery limited

# Local users may interrogate the ntp server more closely.
restrict 127.0.0.1
restrict ::1

#restrict 192.168.137.13 nomodify notrap noquery
# Needed for adding pool entries
restrict source notrap nomodify noquery

# Clients from this (example!) subnet have unlimited access, but only if
# cryptographically authenticated.
#restrict 192.168.123.0 mask 255.255.255.0 notrust


# If you want to provide time to your local subnet, change the next line.
# (Again, the address is an example only.)
#broadcast 192.168.123.255

# If you want to listen to time broadcasts on your local subnet, de-comment the
# next lines.  Please do this only if you trust everybody on the network!
#disable auth
#broadcastclient

#Changes recquired to use pps synchonisation as explained in documentation:
#http://www.ntp.org/ntpfaq/NTP-s-config-adv.htm#AEN3918

#server 127.127.8.1 mode 135 prefer    # Meinberg GPS167 with PPS
#fudge 127.127.8.1 time1 0.0042        # relative to PPS for my hardware

#server 127.127.22.1                   # ATOM(PPS)
#fudge 127.127.22.1 flag3 1            # enable PPS API
#

restrict 127.0.0.1
server 192.168.137.13 prefer

1.2设置ntp

服务端：
一般安装后，就不需要其他操作
使用ntpq -p可以查看同步服务器关系

启动ntp服务：
systemctl start ntp
systemctl status ntp

客户端：
停止ntp:
systemctl stop ntp
同步时钟：ntpdate 192.168.137.13
启动ntp：
systemctl start ntp
使用ntpq -p查看同步关系：

参数refid表示，祖先时钟服务器

2.设置服务器使用东八区时间

mv /etc/localtime /etc/localtime.bak
ln -s /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
为/usr/share/zoneinfo/Asia/Shanghai建立软连接，名字为/etc/localtime

3.数据库设置东八区时间

检查数据库时区

> show variables like "%time_zone%";
+------------------+--------+
| Variable_name    | Value  |
+------------------+--------+
| system_time_zone | CST    |
| time_zone        | SYSTEM |
+------------------+--------+

time_zone说明MySQL使用system的时区，system_time_zone说明system使用CST时区

1. 在线设置东八区

set global time_zone='+8:00';
set time_zone='+8:00';
flush privileges;

设置之后：

2. 配置文件设置东八区

# vim /etc/my.cnf ##在[mysqld]区域中加上
 
default-time_zone = '+8:00'

重启mysql

以上选取一种设置
最后，mysql连接信息增加：serverTimezone=Asia/Shanghai

4.docker容器时区不正确

docker exec -it <container> /bin/bash
ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime

重启容器
或者运行容器时，加上挂载参数

docker run -d <container> -v /etc/timezone:/etc/timezone -v /etc/localtime:/etc/localtime

5.修改Java虚拟机时间

java -jar -Duser.timezone=GMT+08 xxx.jar