OSETC TECH

CentOS 7 / RHEL 7 : Systemctl Command

There is a new command named “systemctl” on CentOS 7 or RHEL 7 system, this command control the systemd system and service manager. and may be used to introspect and control the state of the system and service manager. it is integrated with “chkconfig” and “service” command. How to use this command in centos 7 system? this post will show you some examples.

CentOS 7 / RHEL 7 Systemctl Command To Start/Stop Service 

Assuming you want to start or stop a apache service using the following command:

systemctl start httpd.service  #====> start httpd service

systemctl stop httpd.service  #===> stop httpd service

systemctl restart httpd.service #===> restart httpd service

If you want tostart  the service automatically  while system startup, issue the following command:

systemctl enable httpd.service  #====> start httpd.service while system startup

systemctl disable httpd.service  #====> do not start httpd.service while system startup

CentOS 7 / RHEL 7 Systemctl Command Check Service Status

Using the following systemctl command to check the status of one service , type:

systemctl status *.service

Example: checking the status of smartd service

[root@osetc Desktop]# systemctl status httpd.service

httpd.service

Loaded: not-found (Reason: No such file or directory)

Active: inactive (dead)

[root@osetc Desktop]# systemctl status smartd.service

smartd.service - Self Monitoring and Reporting Technology (SMART) Daemon

Loaded: loaded (/usr/lib/systemd/system/smartd.service; enabled)

Active: active (running) since Wed 2014-12-03 09:13:30 EST; 1h 53min ago

Main PID: 810 (smartd)

CGroup: /system.slice/smartd.service

└─810 /usr/sbin/smartd -n -q never

Dec 03 09:13:30 itsprite systemd[1]: Started Self Monitoring and Reporting ...n.

Dec 03 09:13:31 itsprite smartd[810]: smartd 6.2 2013-07-26 r3841 [x86_64-l...d)

Dec 03 09:13:31 itsprite smartd[810]: Copyright (C) 2002-13, Bruce Allen, C...rg

Dec 03 09:13:31 itsprite smartd[810]: Opened configuration file /etc/smartm...nf

Dec 03 09:13:31 itsprite smartd[810]: Configuration file /etc/smartmontools...es

Dec 03 09:13:31 itsprite smartd[810]: Device: /dev/sda, opened

Dec 03 09:13:31 itsprite smartd[810]: Device: /dev/sda, [VMware,  VMware Vi...GB

Dec 03 09:13:31 itsprite smartd[810]: Device: /dev/sda, IE (SMART) not enab...ce

Dec 03 09:13:31 itsprite smartd[810]: Try 'smartctl -s on /dev/sda' to turn...es

Dec 03 09:13:31 itsprite smartd[810]: Monitoring 0 ATA and 0 SCSI devices

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