Objetivo: Para ver o status dos serviços ou habilitar / desabilitar serviços, configure como segue.
[1] Exibir os serviços.
root@debian:~# systemctl -t service
apparmor.service loaded active exited Load AppArmor profiles
blk-availability.service loaded active exited Availability of block devices
console-setup.service loaded active exited Set console font and keymap
cron.service loaded active running Regular background program processing daemon
dbus.service loaded active running D-Bus System Message Bus
getty@tty1.service loaded active running Getty on tty1
ifup@ens18.service loaded active exited ifup for ens18
ifupdown-pre.service loaded active exited Helper to synchronize boot up for ifupdown
keyboard-setup.service loaded active exited Set the console keyboard layout
kmod-static-nodes.service loaded active exited Create list of static device nodes for the current ker>
lvm2-monitor.service loaded active exited Monitoring of LVM2 mirrors, snapshots etc. using dmeve>
lvm2-pvscan@8:5.service loaded active exited LVM event activation on device 8:5
networking.service loaded active exited Raise network interfaces
rsyslog.service loaded active running System Logging Service
ssh.service loaded active running OpenBSD Secure Shell server
systemd-fsck@dev-disk-by\x2duuid-079bc19d\x2d073c\x2d4bc9\x2dbc45\x2d4e90739bde3b.service loaded active exited File System Check on /dev/disk/by-uuid/079bc19d-073c-4>
systemd-journal-flush.service loaded active exited Flush Journal to Persistent Storage
systemd-journald.service loaded active running Journal Service
systemd-logind.service loaded active running User Login Management
systemd-modules-load.service loaded active exited Load Kernel Modules
systemd-random-seed.service loaded active exited Load/Save Random Seed
systemd-remount-fs.service loaded active exited Remount Root and Kernel File Systems
systemd-sysctl.service loaded active exited Apply Kernel Variables
systemd-sysusers.service loaded active exited Create System Users
systemd-timesyncd.service loaded active running Network Time Synchronization
systemd-tmpfiles-setup-dev.service loaded active exited Create Static Device Nodes in /dev
systemd-tmpfiles-setup.service loaded active exited Create Volatile Files and Directories
systemd-udev-trigger.service loaded active exited Coldplug All udev Devices
systemd-udevd.service loaded active running Rule-based Manager for Device Events and Files
systemd-update-utmp.service loaded active exited Update UTMP about System Boot/Shutdown
systemd-user-sessions.service loaded active exited Permit User Sessions
user-runtime-dir@1000.service loaded active exited User Runtime Directory /run/user/1000
user@1000.service loaded active running User Manager for UID 1000
LOAD = Reflects whether the unit definition was properly loaded.
ACTIVE = The high-level unit activation state, i.e. generalization of SUB.
SUB = The low-level unit activation state, values depend on unit type.
33 loaded units listed. Pass --all to see loaded but inactive units, too.
To show all installed unit files use 'systemctl list-unit-files'.
[2] Se houver serviços desnecessários, é possível parar e desabilitar a configuração de início automático como a seguir. (você pode omitir o [.service] das palavras)
root@debian:~# systemctl stop apparmor
root@debian:~# systemctl disable apparmor
Synchronizing state of apparmor.service with SysV service script with /lib/systemd/systemd-sysv-install.
Executing: /lib/systemd/systemd-sysv-install disable apparmor
Removed /etc/systemd/system/sysinit.target.wants/apparmor.service.