Deploying Dynatrace OneAgent for Full-Stack Linux Monitoring

The Challenge: Eliminating Manual Instrumentation

Traditional monitoring often requires developers to manually add SDKs or agents to every single application runtime. This creates a maintenance burden and leads to \"monitoring gaps\" where some services are tracked while others remain invisible. The goal is to achieve full-stack visibility—covering the host, the process, and the application code—using a single installation point.

The Takeaway: By deploying the Dynatrace OneAgent, you shift from per-app configuration to host-level instrumentation. The agent automatically discovers supported runtimes (Java, Node.js, .NET) and injects the necessary monitoring hooks into the process memory at startup, providing distributed tracing without code changes.

Prerequisites and Environment Readiness

Before running the installation script, verify the following system requirements to prevent deployment failure or performance degradation:

• Network Access: The host must have outbound HTTPS access (Port 443) to your Dynatrace SaaS tenant or Managed cluster.
• Disk Space: Ensure at least 2GB of free space in /var/lib/dynatrace. If the disk fills, the agent may crash or stop reporting metrics.
• Kernel Compatibility: If using a hardened Linux kernel (e.g., SELinux in enforcing mode or custom security modules), verify that the OneAgent driver can load. On modern kernels, OneAgent leverages eBPF (Extended Berkeley Packet Filter) to collect network and system metrics without modifying the kernel.
• Permissions: You must have root or sudo privileges to install the agent binary and configure the system services.

Installation Procedure

The OneAgent installation is handled via a shell script provided by your Dynatrace environment. This script handles the binary deployment and the registration of the host to your tenant.

1. Download and Execute the Installer

Run the following commands on the target Linux server. Replace the placeholders with the actual values provided in your Dynatrace Deployment screen:

# Download the installer script
wget -O Dynatrace-OneAgent-Linux.sh 

# Make the script executable
chmod +x Dynatrace-OneAgent-Linux.sh

# Execute the installer with root privileges
sudo ./Dynatrace-OneAgent-Linux.sh PAUSE_LAW=false

Risk Note: Running the installer as root is required because the agent must install a kernel-mode driver or eBPF probes to capture host-level CPU and memory metrics accurately.

2. Verify Service Status

Once the script completes, check that the OneAgent service is active and running on the host:

# Check the status of the OneAgent service
systemctl status dynatraceoneagent

Validating Full-Stack Visibility

Installation success is not defined by a \"completed\" script, but by the appearance of data in the Dynatrace console. Perform these four checks to ensure the agent is functioning correctly:

Check	Action	Expected Result
Host Status	Navigate to Deployment Status in the UI.	The host is listed as \"Online\".
Topology	Open the Smartscape map.	The host is linked to its running processes and services.
Instrumentation	Check the Processes view.	Runtimes (e.g., JVM) show as \"Monitored\" rather than \"Detected\".
Trace Flow	Send a request to the app; check Service Flow.	A distributed trace appears showing the request path.

Resource Overhead and Limitations

While OneAgent is designed for efficiency, it does consume system resources. In a production environment, monitor the following:

• CPU/RAM: The agent typically consumes a small percentage of CPU and a fixed amount of RAM for the watchdog process. Validate this in a staging environment before deploying to high-load production servers.
• Runtime Support: While most common languages are supported, some niche or very old runtimes may only be \"detected\" (host-level metrics) rather than \"instrumented\" (code-level metrics).

Rollback and Removal

If the agent causes instability or is no longer needed, use the built-in uninstall script. This removes the binaries and the kernel driver/eBPF probes.

# Run the uninstall script located in the installation directory
sudo /opt/dynatrace/oneagent/agent/uninstall.sh

After running the uninstall script, reboot the server if you need to ensure all kernel-level hooks are completely cleared from memory.