How to Find Running Services in Linux with Systemd and Systemctl Commands

The latest operating system advancements rely on control technology to help users check their server services’ work. Users in IT gain self-assurance and operational ability when they learn how to find running services with Systemd commands. Users need this knowledge to solve problems in addition to enhancing system efficiency and securing systems. The article shows you how to operate Systemd while teaching service management for Linux and giving actual examples of system performance.

Introduction to Systemd and Service Management

System process management in Linux operating systems has been recognized historically for its three characteristics: flexibility, robustness, and efficiency. Systems that run the Linux operating system used to depend on the older Sys init system together with other init systems for initial boot service and management. However, as the complexity of systems increased, the need for a more modern, efficient, and reliable method of managing services led to the adoption of Systemd.

Systemd is an init system and service manager that has become the default on many popular Linux distributions, including Fedora, Ubuntu, CentOS, and Debian. Systemd was developed with parallelization capabilities, dependency administration tools, as well as logging functions to accelerate boot time and offer refined service management control. We will analyze the procedure of locating active services on Linux systems through Systemd command execution in this document.

Why Systemd Became the Standard in Linux

Because of Linux needs the system required a reliable solution to manage its performance. Systemd was created due to init system problems by offering complex controls that enhance the traditional system. The improved performance and system management convince administrators the system will operate smoothly.

The Advantages of Systemd

• Parallel Service Startup: Unlike older init systems, Systemd can start services concurrently, reducing overall boot time.
• Dependency Management: Systemd understands service dependencies, ensuring that services start in the correct order and reducing the likelihood of errors.
• Unified Configuration: By using unit files for configuration, Systemd provides a consistent and simplified approach to managing services.
• Powerful Logging: Integrated with the Journal, Systemd logs are more detailed and easier to parse than traditional syslog messages.
• Robust Process Tracking: Systemd can track the lifecycle of processes, ensuring that even services spawned by other services are properly managed.

The Traditional vs. Modern Approach

System management principles transform when users migrate from traditional init systems to Systemd. Traditional methods proved successful for basic systems, yet contemporary complicated applications, along with multi-services systems, ms need an updated and reactive management system. Systemd provides a contemporary framework that enables administrators to execute service startup and maintain time-based monitoring capabilities without complications.

The system transformation brought improved performance alongside reliability which created new possibilities for innovative service management practices of the future. The acceptance of Systemd enables administrators to combine traditional understanding with contemporary approaches when they optimize Linux system performance.

Getting Started: Essential Systemd Commands

The basic interaction with the Systemd system through Systemctl requires straightforward skills to properly manage Linux services. The crucial command syntax appears next in a manner that will make readers more comfortable and confident.

Basic Systemctl Commands

List All Units:

systemctl list-units

1. This command displays all active units, including services, sockets, and other types.

List Only Services:

systemctl list-units --type=service

2. This filters the output to show only service units.

Check Service Status:

systemctl status <service-name>

3. Replace <service-name> with the name of the service to get detailed information about its status.

Start a Service:

systemctl start <service-name>

4. This command starts a service immediately.

Stop a Service:

systemctl stop <service-name>

5. This stops the specified service.

Restart a Service:

systemctl restart <service-name>

6. This stops and then starts the service again, which is useful when applying configuration changes.

Enable/Disable a Service at Boot:

systemctl enable <service-name>

systemctl disable <service-name>

7. Enabling a service configures it to start at boot while disabling it prevents it from starting automatically.

Through their Linux environment administrators can access service control features by using Systemd commands. System problems become easier to solve with the basic commands that help administrators improve their abilities to handle services.

Listing All Running Services

System service listings form the key duty of Linux administrators who execute system-based procedures. Service listings serve administrators for work performance because they need them to verify configurations, check system statuses, and resolve Linux technical problems.

Using Systemctl to List Running Services

The command to list all active service units is straightforward:

systemctl list-units --type=service --state=running

Breaking Down the Command:

• –type=service filters the output to show only service units.
• –state=running further refines the list to include only services that are currently active.

This command outputs a list with details such as the service name, load state, active state, and description. The output might look something like this:

UNIT	LOAD	ACTIVE	SUB	DESCRIPTION
sshd.service	loaded	active	running	OpenSSH Daemon
Network.service	loaded	active	running	Network Service
Cron.service	loaded	active	running	Regular background program processing daemon

Additional Options for More Detailed Output

Advanced monitoring data about services can be retrieved through the addition of –no-pager option or by selecting systemctl status.

systemctl status sshd.Service

The command delivers detailed information showing process IDs and recent log records together with dependency tree structures that help troubleshooting efforts.

Filtering and Searching Services with Systemd

Hundreds of service numbers require environmental condition control through searching and filtering operations, which the management system conducts. The systemd control system supplies various commands that serve user demands for information.

Using Grep for Filtering

A common approach is to pipe the output of Systemd commands into grep to search for specific keywords. For example, if you want to find all services related to networking:

systemctl list-units --type=service --state=running | grep network

This command will return only those services with the word “network” in their name or description.

Utilizing Built-In Filtering Options

Systemd provides built-in options to filter the output:

Filtering by State:

Apart from running, you can filter by states like failed, dead, or inactive. For example:

systemctl list-units --type=service --state=failed

• This lists services that have encountered errors.

Filtering by Load:
The –all flag can be useful to display all units regardless of their current state:

systemctl list-units --type=service --all

Customizing Output with Additional Options

For even greater control, Systemd commands allow customization of the output format. The –no-legend and –plain options can clean up the display for scripting purposes. For example:

systemctl list-units --type=service --state=running --no-legend --plain

This command is particularly useful in automated scripts where you want to process the output without extra formatting.

Advanced Techniques for Service Monitoring

After mastering basic concepts it is time to learn advanced techniques that help service monitoring and management. The examination of system performance, together with reliability, receives detailed attention through the implementation of these investigative approaches.

Using Journalctl for Log Analysis

While Systemctl provides service status information, Journalctl is the tool for digging into the logs generated by those services. To view logs for a particular service, use:

journalctl -u <service-name>

Examples of Journalctl Usage:

View Recent Logs:

journalctl -u sshd. service -n 50

• This displays the last 50 log entries for the SSH daemon.

Follow Logs in Real-Time:

journalctl -u sshd.service -f

• Similar to tail-f, this command shows real-time log updates for the specified service.

Filter by Time:

journalctl -u cron.service --since "2025-03-01" --until "2025-03-20"

• These filters log entries within a specific date range, which is invaluable for troubleshooting issues that occur during a defined time window.
  

Combining Systemctl and Journalctl for Comprehensive Monitoring

A joint operation of Systemctl and Journalctl enables administrator teams to build in-depth monitoring systems. The administrator first checks service status through Systemctl before analyzing logs via Journalctl to gain an understanding of complete service failure patterns.

Automating Service Monitoring

Installation of cron jobs together with configuration management tools such as Ansible or Puppet should be used to perform periodic checks on critical service status. The setup provides instant notifications about disruptions and performance problems.

Using Third-Party Tools with Systemd

Graphical dashboards and alerting capabilities exist today because third-party monitoring tools now work with Systemd. The combination of tools Grafana, Prometheus and Zabbix enables processing Systemd metrics and logs to provide users with an integrated system health monitoring view. The collaboration between Systemd commands and these tools generates elevated power through the union of administrative methods and data-driven decision systems.

Practical Use Cases and Examples

Let’s consider some real-world scenarios where understanding and using Systemd commands can significantly enhance system management.

Scenario 1: Diagnosing a Failing Service

Programmers need to establish a verification process to assess web server operational states when managing startup system failures. The verification procedure for service operation begins by assessing the existing operational status. Use the following command:

systemctl status apache2.Service

Check the output to find any error messages together with recent log entries and dependency issues. Moving on to service logs becomes necessary when the service demonstrates failure characteristics:

journalctl -u apache2. service -n 100

The assessment of logs could detect problems arising from misconfigurations together with resource limitations. Knowledge gained from the information lets you modify configurations and distribute resources to maintain service stability.

Scenario 2: Auditing Running Services for Security

The security practices of managers include routine evaluations of running services to verify that unessential processes that consume resources and expose vulnerabilities are eliminated. A complete list of active services should be generated to identify any abnormal or old software components:

systemctl list-units --type=service --state=running | grep -i "old"

This command can help identify legacy services that might need updating or removal. Further investigation into these services can prevent potential security breaches.

Scenario 3: Performance Optimization and Resource Management

Resource optimization becomes the essential decision factor that production environments must consider. Users require knowledge about the operational status of resource-demanding services because a database serves as an example:

systemctl status mysql.Service

Check the CPU and memory utilization by using system monitoring tools top or htop. Measure resource usage levels to confirm whether service standards need modification or if service will be optimized through maintenance and load distribution across multiple units.

Scenario 4: Automated Monitoring and Reporting

Your system needs to generate daily automatic reports which assess both service uptime and performance indicators. Using Systemd commands together with shell scripting enables automated execution of such tasks. A script should be designed to monitor significant services and record all system errors:

#!/bin/bash
services=("sshd" "apache2" "mysql")
for service in "${services[@]}"; do
    If! systemctl is-active --quiet $service.service; then
        echo "Alert: $service is not running on $(date)" >> /var/log/service-monitor.log
    fi
done

This script, when added to cron, will automatically check service statuses and alert you to any issues streamlining your system administration workflow.

Troubleshooting and Debugging Services

System management excellence fails to prevent all possible system-related problems. The key approach during service failure or unexpected behavior is troubleshooting. The following breakdown demonstrates a method to use Systemd commands in systematic debugging practice.

Common Issues and Their Diagnosis

Service Fails to Start:
When a service fails to start, use:

systemctl status <service-name>

1. Look for error messages or misconfigured dependencies. Next, check the logs with Journalctl for more detailed error messages.

Service Hangs or Crashes:
A hanging service develops from resource limitation problems as well as deadlocks. Next, check system resource utilization and review system logs:

journalctl -u <service-name> -f

2. This can help identify real-time issues.
3. Configuration Errors:
   Incorrect configurations are a common culprit. If a recent change caused a service to fail, review the associated unit file, check for syntax errors, and validate the configuration. Many distributions provide utilities (e.g., apachectl configtest for Apache) to test configurations before applying changes.

Advanced Debugging with Systemd

The Sysd process requires debugging through the debug logging function to activate advanced diagnostic capabilities. The configuration setup needs debug options inserted into the Systemd service unit file during the pre-loading phase if the feature is available:

systemctl daemon-reload
systemctl restart <service-name>

This process can provide more granular logging output, assisting in pinpointing the exact cause of issues.

Common Debugging Tools

• strace:
  For tracking system calls and signals:

strace -p <PID>

• lsof:
  For listing open files and network connections:

lsof -p <PID>

• systemd-analyze:
  To examine the boot process and identify slow services:
  systemd-analyze blame

By combining these tools with Systemd commands, administrators can thoroughly investigate issues, ensuring minimal downtime and rapid recovery.

Integrating Systemd with Other Linux Tools

Systemd does not operate in isolation. Integrating it with other Linux administration tools can greatly enhance your management capabilities.

Scripting with Bash

Through its functional operations, Bash scripts enable automated connection between logical components and Systemd commands. The automated differential service checks operate within the maintenance script before beginning any service restart process. Through their combined scripts, the system achieves quick performance and protects users from accidental errors caused by human contact.

Using Python for Automation

Python is a powerful tool for system administration, and libraries like subprocess make it easy to execute Systemd commands. Here’s a quick example:

import subprocess
def check_service_status(service):
    result = subprocess.run(['systemctl', 'is-active', service], capture_output=True, text=True)
    if result.stdout.strip() != 'active':
        print(f"Alert: {service} is not running!")
    Else:
        print(f"{service} is running smoothly.")
check_service_status('apache2.service')

This Python script executes a Systemd command and checks whether the service is active. Such automation can be extended to build comprehensive monitoring dashboards.

Integrating with Configuration Management Tools

Large modern IT setups depend on configuration management software, including Ansible, Puppet and Chef, to control their growing system networks. Multiple servers can receive Systemd commands through these uniform management tools. The tasks within an Ansible playbook manage service operations, which include starting, stopping, and restarting them:

- name: Ensure Apache is running
  systemd:
    name: apache2
    state: started
    enabled: yes

This integration streamlines service management across your infrastructure, reducing manual overhead and ensuring consistency.

Combining with Log Analysis Tools

Users must utilize either ELK stack (Elasticsearch, Logstash, and Kibana) or Graylog centralized logging solutions to monitor their entire system when combining Systemd logs with these platforms. Through these platforms, administrators access system pattern tracking abilities and warning alert activation while conducting system malfunction identification after Journalctl logs are ingested.

Best Practices for Linux Service Management

Linux service management competencies surpass the level of command proficiency. Service management in Linux operates best by harmonizing best practices, which enhance both security and, reliability and performance. The following direction will lead you toward excellence in managing services through Systemd.

Regular Monitoring and Auditing

• Frequent Checks: Schedule regular audits of your running services using Systemd commands. Use automated scripts to check for services in undesired states and log any anomalies.
• Log Review: Regularly review logs with Journalctl to catch early signs of trouble before they escalate into critical issues.

Keeping Configurations Up-to-Date

• Unit File Management: Maintain and version control your unit files. This ensures that any changes are documented and can be reverted if necessary.
• Configuration Testing: Use built-in tools and commands to test configuration changes before applying them. For example, run configuration tests for web servers and databases after making changes.

Security Considerations

• Least Privilege: Configure services to run with the minimum privileges necessary. Avoid running services as root unless absolutely required.
• Regular Updates: Keep your system and services up-to-date with security patches. Leverage package managers and automated update tools.
• Service Isolation: Where possible, isolate services in containers or virtual machines to limit the impact of any potential security breaches.

Documentation and Training

• Maintain Documentation: Document your processes, scripts, and troubleshooting steps. This not only aids in recovery but also helps onboard new team members.
• Continuous Training: Continued training programs for Systemd command use and best practices in Linux administration should be regularly provided to your team members. Better system management becomes achievable when your team members understand these tools well.

Embracing Innovation While Honoring Tradition

Systemd serves as a contemporary method of service management, yet traditional approaches maintain their worth. Execution of present methodologies alongside new developments creates an all-encompassing strategy. Automated processes, when combined with scripting methods, enhance performance, but they should maintain manual inspection practices and real-time system investigation as core operations.

Proactive Service Recovery

The organization must develop automated restoration systems to sustain essential operational activities. The configuration of Systemd unit file options with a Restart=always parameter needs to appear in rephrased instructions to establish automatic service restarts during system failures. Organizations achieve fewer system outages when they combine proactive recovery techniques with complete system monitoring systems.

Conclusion

System administrators need essential knowledge of running service identification and management through Systemd instructions to perform their duties effectively. Systemd delivers a contemporary system management approach that enables users to list services through filtering functions and solve problems while linking their services to other tools. You can achieve both system protection and reliability performance by combining conventional methods with developing practices in your Linux environments.

Throughout this guide, we’ve explored:

• The evolution and advantages of Systemd over traditional init systems.
• Essential commands for listing, starting, stopping, and monitoring services.
• Techniques for filtering and searching through extensive service lists.
• Advanced debugging practices using Journalctl, strace, and other tools.
• Real-world scenarios that demonstrate how to apply these commands in practical situations.
• The integration of Systemd with scripting languages and configuration management tools.
• Best practices that blend legacy wisdom with modern system administration innovations.

You will gain the ability to resolve problems fast and conduct proactive system management for Linux systems by using this complete approach within an IT environment that becomes more intricate. A solid command of Systemd commands prepares Linux enthusiasts at all skill levels to effectively secure and optimize their systems.

Final Thoughts

Linux service management evolution demonstrates that innovation gains from building new approaches on established and proven foundational techniques. When you integrate these Systemd commands into your workflow, you will discover that traditional and modern management methods establish a reliable system for controlling complex Linux systems.

Accomplished system administration succeeds through both command fluency and decision-making expertise with available tools. Keep experimenting, document your processes, and share your knowledge with your team. In doing so, you will not only improve your system’s reliability and performance but also contribute to a culture of continuous improvement and innovation.

Embrace the challenges and complexities of modern Linux administration with the confidence that comes from a deep understanding of Systemd. The fast-paced IT world demands companies to unite traditional practices with innovative solutions to maintain their leadership position. Systemd gives you the tools needed to tackle all service management problems that appear.

About the writer

Vinayak Baranwal wrote this article. Use the provided link to connect with Vinayak on LinkedIn for more insightful content or collaboration opportunities