@ -1,299 +1,203 @@
systemctl
===
系统服务管理器指令
# **systemctl**
## 说明
**systemctl命令** 是系统服务管理器指令，它实际上将 service 和 chkconfig 这两个命令组合到一起
< table >
< tbody >
< tr >
< td > 任务< / td >
< td > 旧指令< / td >
< td > 新指令< / td >
< / tr >
< tr >
< td > 使某服务自动启动< / td >
< td > chkconfig --level 3 httpd on< / td >
< td > systemctl enable httpd.service< / td >
< / tr >
< tr >
< td > 使某服务不自动启动< / td >
< td > chkconfig --level 3 httpd off< / td >
< td > systemctl disable httpd.service< / td >
< / tr >
< tr >
< td > 检查服务状态< / td >
< td > service httpd status< / td >
< td > systemctl status < / td >
< / tr >
< tr >
< td > 显示所有已启动的服务< / td >
< td > chkconfig --list< / td >
< td > systemctl list-units --type=service< / td >
< / tr >
< tr >
< td > 启动某服务< / td >
< td > service httpd start< / td >
< td > systemctl start httpd.service< / td >
< / tr >
< tr >
< td > 停止某服务< / td >
< td > service httpd stop< / td >
< td > systemctl stop httpd.service< / td >
< / tr >
< tr >
< td > 重启某服务< / td >
< td > service httpd restart< / td >
< td > systemctl restart httpd.service< / td >
< / tr >
< / tbody >
< / table >
## 实例
1.启动nfs服务
```
systemctl
```
2.设置开机自启动
## 选项
```markdown
--system Connect to system manager
-H --host=[USER@]HOST
Operate on remote host
-M --machine=CONTAINER
Operate on local container
-t --type=TYPE List units of a particular type
--state=STATE List units with particular LOAD or SUB or ACTIVE state
-p --property=NAME Show only properties by this name
-a --all Show all loaded units/properties, including dead/empty
ones. To list all units installed on the system, use
the 'list-unit-files' command instead.
-l --full Don't ellipsize unit names on output
-r --recursive Show unit list of host and local containers
--reverse Show reverse dependencies with 'list-dependencies'
--job-mode=MODE Specify how to deal with already queued jobs, when
queueing a new job
--show-types When showing sockets, explicitly show their type
-i --ignore-inhibitors
When shutting down or sleeping, ignore inhibitors
--kill-who=WHO Who to send signal to
-s --signal=SIGNAL Which signal to send
--now Start or stop unit in addition to enabling or disabling it
-q --quiet Suppress output
--no-block Do not wait until operation finished
--no-wall Don't send wall message before halt/power-off/reboot
--no-reload Don't reload daemon after en-/dis-abling unit files
--no-legend Do not print a legend (column headers and hints)
--no-pager Do not pipe output into a pager
--no-ask-password
Do not ask for system passwords
--global Enable/disable unit files globally
--runtime Enable unit files only temporarily until next reboot
-f --force When enabling unit files, override existing symlinks
When shutting down, execute action immediately
--preset-mode= Apply only enable, only disable, or all presets
--root=PATH Enable unit files in the specified root directory
-n --lines=INTEGER Number of journal entries to show
-o --output=STRING Change journal output mode (short, short-iso,
short-precise, short-monotonic, verbose,
export, json, json-pretty, json-sse, cat)
--plain Print unit dependencies as a list instead of a tree
Unit Commands:
list-units [PATTERN...] List loaded units
list-sockets [PATTERN...] List loaded sockets ordered by address
list-timers [PATTERN...] List loaded timers ordered by next elapse
start NAME... Start (activate) one or more units
stop NAME... Stop (deactivate) one or more units
reload NAME... Reload one or more units
restart NAME... Start or restart one or more units
try-restart NAME... Restart one or more units if active
reload-or-restart NAME... Reload one or more units if possible,
otherwise start or restart
reload-or-try-restart NAME... Reload one or more units if possible,
otherwise restart if active
isolate NAME Start one unit and stop all others
kill NAME... Send signal to processes of a unit
is-active PATTERN... Check whether units are active
is-failed PATTERN... Check whether units are failed
status [PATTERN...|PID...] Show runtime status of one or more units
show [PATTERN...|JOB...] Show properties of one or more
units/jobs or the manager
cat PATTERN... Show files and drop-ins of one or more units
set-property NAME ASSIGNMENT... Sets one or more properties of a unit
help PATTERN...|PID... Show manual for one or more units
reset-failed [PATTERN...] Reset failed state for all, one, or more
units
list-dependencies [NAME] Recursively show units which are required
or wanted by this unit or by which this
unit is required or wanted
Unit File Commands:
list-unit-files [PATTERN...] List installed unit files
enable NAME... Enable one or more unit files
disable NAME... Disable one or more unit files
reenable NAME... Reenable one or more unit files
preset NAME... Enable/disable one or more unit files
based on preset configuration
preset-all Enable/disable all unit files based on
preset configuration
is-enabled NAME... Check whether unit files are enabled
mask NAME... Mask one or more units
unmask NAME... Unmask one or more units
link PATH... Link one or more units files into
the search path
add-wants TARGET NAME... Add 'Wants' dependency for the target
on specified one or more units
add-requires TARGET NAME... Add 'Requires' dependency for the target
on specified one or more units
edit NAME... Edit one or more unit files
get-default Get the name of the default target
set-default NAME Set the default target
Machine Commands:
list-machines [PATTERN...] List local containers and host
Job Commands:
list-jobs [PATTERN...] List jobs
cancel [JOB...] Cancel all, one, or more jobs
Snapshot Commands:
snapshot [NAME] Create a snapshot
delete NAME... Remove one or more snapshots
Environment Commands:
show-environment Dump environment
set-environment NAME=VALUE... Set one or more environment variables
unset-environment NAME... Unset one or more environment variables
import-environment [NAME...] Import all or some environment variables
Manager Lifecycle Commands:
daemon-reload Reload systemd manager configuration
daemon-reexec Reexecute systemd manager
System Commands:
is-system-running Check whether system is fully running
default Enter system default mode
rescue Enter system rescue mode
emergency Enter system emergency mode
halt Shut down and halt the system
poweroff Shut down and power-off the system
reboot [ARG] Shut down and reboot the system
kexec Shut down and reboot the system with kexec
exit Request user instance exit
switch-root ROOT [INIT] Change to a different root file system
suspend Suspend the system
hibernate Hibernate the system
hybrid-sleep Hibernate and suspend the system
```
systemctl
```
3.停止开机自启动
```
systemctl
```
4.查看服务当前状态
```
systemctl
```
5.重新启动某服务
```
systemctl
```
6.查看所有已启动的服务
```
systemctl
```
开启防火墙22端口
```
iptables
```
## 实例
如果仍然有问题，
```bash
systemctl reboot # 重启系统
systemctl poweroff # 关闭系统，切断电源
systemctl halt # 关机
systemctl suspend # 暂停系统
systemctl hibernate # 休眠系统
systemctl hybrid-sleep # 让系统进入交互式休眠状态
systemctl rescue # 启动进入救援状态（单用户状态）
systemctl list-units --type=service # 查看所有服务单元
关闭SElinux：
systemd-analyze blame # 显示瀑布状的启动过程流
systemd-analyze critical-chain atd.service # 显示指定服务的启动流
修改`/etc/selinux/config`文件中的`SELINUX=””`为disabled，
localectl set-locale LANG=en_GB.utf8 localectl set-keymap en_GB # 设置本地化参数
彻底关闭防火墙：
timedatectl list-timezones # 显示所有可用的时区
```
sudo
sudo
sudo
```
```sh
1.systemctl
# 重启系统
systemctl reboot
# 关闭系统，切断电源
systemctl poweroff
# CPU停止工作
systemctl halt
# 暂停系统
systemctl suspend
# 让系统进入冬眠状态
systemctl hibernate
# 让系统进入交互式休眠状态
systemctl hybrid-sleep
# 启动进入救援状态（单用户状态）
systemctl rescue
2.systemd-analyze
# 查看启动耗时
systemd-analyze
# 查看每个服务的启动耗时
systemd-analyze blame
# 显示瀑布状的启动过程流
systemd-analyze critical-chain
# 显示指定服务的启动流
systemd-analyze critical-chain atd.service
3.hostnamectl
# 显示当前主机的信息
hostnamectl
# 设置主机名
hostnamectl set-hostname rhel7
4.localectl
# 查看本地化设置
localectl
# 设置本地化参数
localectl set-locale LANG=en_GB.utf8 localectl set-keymap en_GB
5.timedatectl
# 查看当前时区设置
timedatectl
# 显示所有可用的时区
timedatectl list-timezones
# 设置当前时区
timedatectl set-timezone America/New_York
timedatectl set-time YYYY-MM-DD
timedatectl set-time HH:MM:SS
6.loginctl
# 列出当前session
loginctl list-sessions
# 列出当前登录用户
loginctl list-users
# 列出显示指定用户的信息
loginctl show-user ruanyf
# 列出正在运行的 Unit
systemctl list-units
# 列出所有Unit，
systemctl list-units --all
# 列出所有没有运行的 Unit
systemctl list-units --all --state=inactive
# 列出所有加载失败的 Unit
systemctl list-units --failed
# 列出所有正在运行的、类型为 service 的 Unit
systemctl list-units --type=service
除了systemctl status ，还有三个查询状态方法，主要是脚本内部的判断语句使用
# 显示某个 Unit 是否正在运行
systemctl is-active application.service
# 显示某个 Unit 是否处于启动失败状态
systemctl is-failed application.service
# 显示某个 Unit 服务是否建立了启动链接
systemctl is-enabled application.service
```
### 常用systemctl命令
loginctl list-sessions # 列出当前session
loginctl list-users # 列出当前登录用户
loginctl show-user ruanyf # 列出显示指定用户的信息
systemctl is-active application.service # 显示某个 Unit 是否正在运行
systemctl is-failed application.service # 显示某个 Unit 是否处于启动失败状态
systemctl is-enabled application.service # 显示某个 Unit 服务是否建立了启动链接
systemctl daemon-reload # 重载所有修改过的配置文件
systemctl show httpd.service # 显示某个 Unit 的所有底层参数
systemctl set-property httpd.service CPUShares=500 # 设置某个 Unit 的指定属性
systemctl list-dependencies nginx.service # 列出一个unit的所有依赖
systemctl list-unit-files # 列出所有systemctl配置文件
systemctl list-unit-files --type=service # 列出指定类型的配置文件
systemctl list-unit-files --type=target # 查看当前系统的所有 Target
systemctl list-dependencies multi-user.target # 查看一个 Target 包含的所有 Unit
systemctl get-default # 查看启动时的默认 Target
systemctl set-default multi-user.target # 设置启动时的默认 Target
journalctl -k # 查看内核日志（不显示应用日志）
journalctl -b -0 # 查看系统本次启动的日志
journalctl -b -1 # 查看上一次启动的日志（需更改设置）
```sh
# 立即启动一个服务
systemctl start apache.service
# 立即停止一个服务
systemctl stop apache.service
# 重启一个服务
systemctl restart apache.service
# 杀死一个服务的所有子进程
systemctl kill apache.service
# 重新加载一个服务的配置文件
systemctl reload apache.service
# 重载所有修改过的配置文件
systemctl daemon-reload
# 显示某个 Unit 的所有底层参数
$ systemctl show httpd.service
# 显示某个 Unit 的指定属性的值
$ systemctl show -p CPUShares httpd.service
# 设置某个 Unit 的指定属性
systemctl set-property httpd.service CPUShares=500
# 列出一个unit的所有依赖
systemctl list-dependencies nginx.service
# 列出所有systemctl配置文件
systemctl list-unit-files
# 列出指定类型的配置文件
systemctl list-unit-files --type=service
# 查看当前系统的所有 Target
$ systemctl list-unit-files --type=target
# 查看一个 Target 包含的所有 Unit
$ systemctl list-dependencies multi-user.target
# 查看启动时的默认 Target
$ systemctl get-default
# 设置启动时的默认 Target
systemctl set-default multi-user.target
# 查看所有日志（默认情况下 ，只保存本次启动的日志）
journalctl
# 查看内核日志（不显示应用日志）
journalctl -k
# 查看系统本次启动的日志
journalctl -b
journalctl -b -0
# 查看上一次启动的日志（需更改设置）
journalctl -b -1
# 查看指定时间的日志
journalctl --since="2012-10-30 18:17:16"
journalctl --since "20 min ago"
journalctl --since yesterday
journalctl --since "2015-01-10" --until "2015-01-11 03:00" journalctl --since 09:00 --until "1 hour ago"
# 显示尾部的最新10行日志
journalctl -n
# 显示尾部指定行数的日志
journalctl -n 20
# 实时滚动显示最新日志
journalctl -f
# 查看指定服务的日志
journalctl /usr/lib/systemd/systemd
# 查看指定进程的日志
journalctl _PID=1
# 查看某个路径的脚本的日志
journalctl /usr/bin/bash
# 查看指定用户的日志
journalctl _UID=33 --since today
# 查看某个 Unit 的日志
journalctl -u nginx.service
journalctl -u nginx.service --since today
# 实时滚动显示某个 Unit 的最新日志
journalctl -u nginx.service -f
# 合并显示多个 Unit 的日志
journalctl -u nginx.service -u php-fpm.service --since today
journalctl -n 20 # 显示尾部指定行数的日志
journalctl -f # 实时滚动显示最新日志
journalctl _PID=1 # 查看指定进程的日志
journalctl _UID=33 --since today # 查看指定用户的日志
journalctl -u nginx.service --since today # 查看某个 Unit 的日志
journalctl -u nginx.service -f # 实时滚动显示某个 Unit 的最新日志
journalctl -u nginx.service -u php-fpm.service --since today # 合并显示多个 Unit 的日志
journalctl -p err -b
# 查看指定优先级（ ） ，
0: emerg
1: alert
@ -303,18 +207,12 @@ journalctl -u nginx.service -u php-fpm.service --since today
5: notice
6: info
7: debug
journalctl -p err -b
# 日志默认分页输出，--no-pager 改为正常的标准输出
journalctl --no-pager
# 以 JSON 格式（单行）输出
journalctl -b -u nginx.service -o json
# 以 JSON 格式（多行）输出，可读性更好
journalctl -b -u nginx.serviceqq -o json-pretty
# 显示日志占据的硬盘空间
journalctl --disk-usage
# 指定日志文件占据的最大空间
journalctl --vacuum-size=1G
# 指定日志文件保存多久
journalctl --vacuum-time=1years
journalctl --no-pager # 日志默认分页输出，--no-pager 改为正常的标准输出
journalctl -b -u nginx.service -o json # 以 JSON 格式（单行）输出
journalctl -b -u nginx.serviceqq -o json-pretty # 以 JSON 格式（多行）输出，可读性更好
journalctl --disk-usage # 显示日志占据的硬盘空间
journalctl --vacuum-size=1G # 指定日志文件占据的最大空间
journalctl --vacuum-time=1years # 指定日志文件保存多久
```
root
6 years ago