📅 最后修改于: 2023-12-03 15:32:42.867000 🧑 作者: Mango
在Linux系统中，systemd是一个系统和服务管理器。systemctl是与systemd来进行交互的命令行工具，用来管理systemd系统守护进程的状态，以及systemd单元和服务的启动、停止、启用和禁用等操作。
本文将介绍如何使用systemctl进行资源管理。
使用systemctl命令，不带任何参数，可以查看系统中所有服务的状态。例如：
systemctl
输出结果类似于：
UNIT LOAD ACTIVE SUB DESCRIPTION
proc-sys-fs-binfmt_misc.automount loaded active waiting Arbitrary Executable File Formats File System Automount Point
sys-devices-pci0000:00-0000:00:04.0-virtio0-block-vda.vda1.device loaded active plugged /sys/devices/pci0000:00/0000:00:04.0/virtio0/block/vda/vda1
sys-devices-pci0000:00-0000:00:04.0-virtio0-net-enp0s4.device loaded active plugged /sys/devices/pci0000:00/0000:00:04.0/virtio0/net/enp0s4
sys-devices-pci0000:00-0000:00:05.0-virtio0-input-input0.event0.device loaded active plugged /sys/devices/pci0000:00/0000:00:05.0/virtio0/input/input0/event0
sys-devices-pci0000:00-0000:00:05.0-virtio0-input-input0.device loaded active plugged /sys/devices/pci0000:00/0000:00:05.0/virtio0/input/input0
sys-devices-pci0000:00-0000:00:06.0-virtio0-virtio1-input-input0.event0.device loaded active plugged /sys/devices/pci0000:00/0000:00:06.0/virtio0/virtio1/input/input0/event0
sys-devices-pci0000:00-0000:00:06.0-virtio0-virtio1-input-input0.device loaded active plugged /sys/devices/pci0000:00/0000:00:06.0/virtio0/virtio1/input/input0
sys-devices-pci0000:00-0000:00:06.0-virtio0-virtport1p1.device loaded active plugged /sys/devices/pci0000:00/0000:00:06.0/virtio0/virtport1p1
systemd-ask-password-console.path loaded active waiting Dispatch Password Requests to Console Directory Watch
systemd-ask-password-wall.path loaded active waiting Forward Password Requests to Wall Directory Watch
init.scope loaded active running System and Service Manager
session-1.scope loaded active running Session 1 of user root
-:pam_unix(sudo:session):session-2 loaded active running pam_unix(sudo:session): session 2 opened for user root by (uid=0)
cronie.service loaded active running Periodic Command Scheduler
dbus.service loaded active running D-Bus System Message Bus
firewalld.service loaded active running firewalld - dynamic firewall daemon
kdump.service loaded active exited Crash recovery kernel arming
kmod-static-nodes.service loaded active exited Create list of static device nodes for the current kernel
network.service loaded active exited LSB: Bring up/down networking
rsyslog.service loaded active running System Logging Service
sshd.service loaded active running OpenSSH server daemon
systemd-journald.service loaded active running Journal Service
systemd-logind.service loaded active running Login Service
systemd-udevd.service loaded active running udev Kernel Device Manager
tuned.service loaded active running Dynamic System Tuning Daemon
upower.service loaded active running Daemon for power management
yum-cron.service loaded active running Run automatic yum updates as a cron job
crond.service loaded inactive dead Regular background program processing daemon
getty@tty1.service loaded inactive dead Getty on tty1
rc-local.service loaded inactive dead /etc/rc.local Compatibility
systemd-journal-flush.service loaded inactive dead Flush Journal to Persistent Storage
systemd-remount-fs.service loaded inactive dead Remount Root and Kernel File Systems
使用systemctl命令，加上参数servicename（指定服务名称），可以查看单个服务的状态。例如：
systemctl status cronie.service
输出结果类似于：
● cronie.service - Periodic Command Scheduler
Loaded: loaded (/usr/lib/systemd/system/cronie.service; enabled; vendor preset: enabled)
Active: active (running) since Fri 2021-07-30 10:30:29 CST; 2 days ago
Main PID: 815 (crond)
CGroup: /system.slice/cronie.service
└─815 /usr/sbin/crond -n
Jul 30 10:30:29 localhost.localdomain systemd[1]: Starting Periodic Command Scheduler...
Jul 30 10:30:29 localhost.localdomain crond[815]: (CRON) INFO (RANDOM_DELAY will be scaled with factor 74% if used.)
Jul 30 10:30:29 localhost.localdomain systemd[1]: Started Periodic Command Scheduler.
使用systemctl命令，加上参数start和servicename（指定服务名称），可以启动单个服务。例如：
systemctl start cronie.service
使用systemctl命令，加上参数stop和servicename（指定服务名称），可以停止单个服务。例如：
systemctl stop cronie.service
使用systemctl命令，加上参数restart和servicename（指定服务名称），可以重启单个服务。例如：
systemctl restart cronie.service
使用systemctl命令，加上参数enable和servicename（指定服务名称），可以设置单个服务开机自启动。例如：
systemctl enable cronie.service
使用systemctl命令，加上参数disable和servicename（指定服务名称），可以设置单个服务禁止开机自启动。例如：
systemctl disable cronie.service
使用systemctl命令，可以管理系统中的所有服务，包括查询服务状态、启动、停止、重启、开机自启动和禁止开机自启动等操作。可以帮助Linux管理员更高效地进行资源管理。