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Initial Settings : Services

 [1]. It's possible to display services' status like follows.

# the list of services that are active now

[root@dlp ~]# systemctl -t service

UNIT                            LOAD   ACTIVE SUB     DESCRIPTION

atd.service                     loaded active running Job spooling tools

auditd.service                  loaded active running Security Auditing Service

chronyd.service                 loaded active running NTP client/server

crond.service                   loaded active running Command Scheduler

dbus.service                    loaded active running D-Bus System Message Bus

.....

.....

user-runtime-dir@0.service      loaded active exited  /run/user/0 mount wrapper

user@0.service                  loaded active running User Manager for UID 0

vdo.service                     loaded active exited  VDO volume services


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.


45 loaded units listed. Pass --all to see loaded but inactive units, too.

To show all installed unit files use 'systemctl list-unit-files'.


# list of all services

[root@dlp ~]# systemctl list-unit-files -t service

UNIT FILE                                   STATE

arp-ethers.service                          disabled

atd.service                                 enabled

auditd.service                              enabled

autovt@.service                             enabled

blk-availability.service                    disabled

.....

.....

user-runtime-dir@.service                   static

user@.service                               static

vdo.service                                 enabled


181 unit files listed.

[2]. Stop and turn OFF auto-start setting for a service if you don'd need it. (it's smartd as an example below)

[root@dlp ~]# systemctl stop smartd

[root@dlp ~]# systemctl disable smartd

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