Service Management on CentOS 7¶
CentOS 7 uses systemd
for service management. systemd
is an alternative to older systems such as SysVinit
which was used by CentOS 6.
Here are a few changes that you need to be aware of.
Check status of services¶
You can use the command below to check the status of your services.
[root@centos ~]# systemctl status httpd
httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; vendor preset: disabled)
Active: active (running) since Wed 2016-08-03 16:33:11 BST; 6 days ago
Docs: man:httpd(8)
man:apachectl(8)
Process: 22622 ExecReload=/usr/sbin/httpd $OPTIONS -k graceful (code=exited, status=0/SUCCESS)
Main PID: 7671 (httpd)
Status: "Total requests: 0; Current requests/sec: 0; Current traffic: 0 B/sec"
Memory: 11.9M
CGroup: /system.slice/httpd.service
├─ 7671 /usr/sbin/httpd -DFOREGROUND
├─22643 /usr/sbin/httpd -DFOREGROUND
├─22644 /usr/sbin/httpd -DFOREGROUND
├─22645 /usr/sbin/httpd -DFOREGROUND
├─22647 /usr/sbin/httpd -DFOREGROUND
└─22658 /usr/sbin/httpd -DFOREGROUND
Aug 03 16:33:11 host-192-168-0-27 systemd[1]: Starting The Apache HTTP Server...
Aug 03 16:33:11 host-192-168-0-27 systemd[1]: Started The Apache HTTP Server.
Aug 07 03:38:31 centos systemd[1]: Reloaded The Apache HTTP Server.
Hint: Some lines were ellipsized, use -l to show in full.
Restart your services¶
In this example, you will restart, stop and start the httpd
services.
systemctl restart httpd
systemctl stop httpd
systemctl start httpd
Check list of all services enabled or disabled on boot¶
You can check the list of services by using the following command.
[root@centos ~]# systemctl list-unit-files --type=service
UNIT FILE STATE
acpid.service enabled
arp-ethers.service disabled
auditd.service enabled
[email protected] disabled
blk-availability.service disabled
brandbot.service static
cloud-config.service enabled
cloud-final.service enabled
cloud-init-local.service enabled
cloud-init.service enabled
console-getty.service disabled
console-shell.service disabled
[email protected] static
cpupower.service disabled
crond.service enabled
dbus-org.freedesktop.hostname1.service static
dbus-org.freedesktop.locale1.service static
dbus-org.freedesktop.login1.service static
dbus-org.freedesktop.machine1.service static
dbus-org.freedesktop.network1.service invalid
dbus-org.freedesktop.NetworkManager.service enabled
dbus-org.freedesktop.nm-dispatcher.service enabled
dbus-org.freedesktop.timedate1.service static
dbus.service static
debug-shell.service disabled
dnsmasq.service disabled
docker.service enabled
dovecot.service enabled
dracut-cmdline.service static
dracut-initqueue.service static
You can also use the guide below for a quick conversion from SysVinit
to systemd