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In this tutorial I will share the commands which you can use to list systemctl services along with their state. You can use these methods in scripts to add service status checks to make sure service is in running or failed state.
Are you new to systemd and systemctl?
With RHEL/CentOS 7, now we have services based on systemd and the SysV scripts are deprecated. If you are new to
systemd then I would suggest reading this another article where I have done 1:1 comparison between SysV and systemd services.
systemd the traditional Linux commands such as
chckconfig, service etc are not supported any more. Although you can still use these commands but they can be removed in upcoming releases.
For example, with RHEL/CentOS 6 we used to use
chkconfig to enable or disable service at different run level. Now with RHEL 8 also I see we are allowed to use
# chkconfig postfix on Note: Forwarding request to 'systemctl enable postfix.service'. Created symlink /etc/systemd/system/multi-user.target.wants/postfix.service → /usr/lib/systemd/system/postfix.service.
But the request is internally routed to
systemctl. Similarly you can restart a service using traditional command i.e.
service <service_name> <action>. For example, to restart
# service sshd restart Redirecting to /bin/systemctl restart sshd.service
This request was also transferred to
So I hope you understood the point, at the time of writing this article with RHEL 8.1
# cat /etc/redhat-release Red Hat Enterprise Linux release 8.1 (Ootpa)
we are still allowed to use traditional SysV commands but it can be removed in any release now. So I would strongly recommend users to start using
systemctl commands as they are very user friendly and powerful tool with the amount of options they support.
systemdwe have unit files which are further classified into
targetetc. So you must be very clear on your requirement if you wish to list only services, or sockets or any other type of unit.
systemctl list unit files loaded in memory
List active unit files
First of all we will list all the unit files which are currently available in the memory of our Linux server. This command will list only the active units from the server's memory:
# systemctl list-units
List all the unit files
To list all the units independent of their state add "
--all" to this command
# systemctl list-units --all
As you can see now it is loading all the unit files including
inactive unit files
systemctl list installed unit files
list-units shows the list of units which are currently loaded in the memory but not necessarily installed on the server. To view the list of unit files which are currently installed on our server we use:
# systemctl list-unit-files
List type of unit files
There can be different types of unit files such as service, socket, mount etc. To further filter the unit files we can add
type= argument with
list-unit-files. The argument should be a comma-separated list of unit types.
systemctl list services
To list all the installed
systemctl services from our Linux server:
# systemctl list-unit-files --type=service
This should give us a complete list of installed services (independent of it's state)
systemctl list mount files
systemd all the partitions and file system are mounted as part of mount type unit files. So we can also list all the mount type unit files available on our server using
# systemctl list-units --all --type=mount
We can further use this with different other type of unit files such as socket, target etc.
List state of services
systemctlwhile to check if a service is running/active/failed/dead etc then you must use
systemctl list-units. To get complete list of supported options with
systemctl list enabled services
To list all the service unit files which are currently in enabled state use
# systemctl list-unit-files --type=service --state=enabled
systemctl list disabled services
We can provided multiple state type with
--state= argument where individual state values will be comma separated. For example to list all the
systemctl service which are either enabled or disabled
# systemctl list-unit-files --type=service --state=enabled,disabled
systemctl list running services
To list the running services we will use
list-units in combination with
# systemctl list-units --type=service --state=running
systemctl list failed services
To list failed services you can use
# systemctl list-units --type=service --state=failed
OR alternatively we can directly use
# systemctl --failed
Check service status of individual unit file
Now the above commands will give you the status of all the unit files which are installed or available on your server. To check the status of individual file we do not want to use those commands in combination with grep and other filter utility.
Now assuming I wish to check the status of
sshd service. So I can use
# systemctl status sshd
which can give me a long list of output along with the actual status such as active, running loaded. Now these three states can also be grepped individually using the properties of a unit file
To check if a
systemctl service is running or not use:
# systemctl show sshd --property=SubState SubState=running
To check if a service is
# systemctl show sshd --property=ActiveState ActiveState=active
OR you can also use:
# systemctl is-active sshd active
To check if a service is loaded or not:
# systemctl show sshd --property=LoadState LoadState=loaded
So we can individually grep the state of individual services using their properties. To list all the properties of a service you can use:
# systemctl show <service>
In this article we learned little bit more about
systemctl unit files. I have explained about the different types of unit files and commands using which we can get the list of running services, sockets, targets etc with
systemctl. We can also get individual status of services using the property of unit files which gives us much more control over the details of each service. We can use these properties in scripts for automation purpose.
Lastly I hope the steps from the article to list running services on Linux was helpful. So, let me know your suggestions and feedback using the comment section.
I have used below external references for this tutorial guide