Docker service stops on OPMS asset.

Products

• CA App Synthetic Monitor

Issue/Introduction

An On-Premise Monitoring Station (OPMS) stops working or fails to initialize because the underlying Docker service stops or fails to start after a system reboot.

When checking the Docker service status, the system logs show output similar to the following:

docker.service: Deactivated successfully.
Stopped Docker Application Container Engine.
Dependency failed for Docker Application Container Engine.
docker.service: Job docker.service/start failed with result 'dependency'.

Docker service had to be started manually.

Environment

Product: Broadcom CA App Synthetic Monitor (ASM)

Component: On-Premise Monitoring Station (OPMS)

Sub-component: Docker Engine

Cause

This is typically an environmental issue related to system boot sequencing. After a system reboot (often following OS patching or updates), the Docker service attempts to start before its required OS dependencies are fully ready.

Resolution

1. Verify OPMS Prerequisites

Ensure that the host environment fully meets all Broadcom OPMS requirements. The Docker process must be able to start properly without environmental restrictions.

• Reference: OPMS Pre-installation Check List

2. Enable Docker Daemon Debug Logs

To capture more events and identify the exact failing dependency, enable debug logging on the Docker daemon.

• Reference: Docker Daemon Logging Documentation

Update your Docker daemon configuration file (typically located at /etc/docker/daemon.json) to include the following debug configuration:

 

{
  "debug": true,
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "10m",
    "max-file": "3"
  }
}

Note: Restart the Docker service after applying this configuration to begin capturing debug logs.

3. Execute Test Scenarios

Once debug logging is enabled, use the following isolation tests to pinpoint the culprit:

• Scenario 1: Baseline Reboot Test Reboot the system in its standard state (without applying any new OS patches or updates). Monitor the boot process to check if the Docker service can start automatically by itself. If errors occur here, review the debug logs to troubleshoot the baseline environment.

• Scenario 2: Post-Patching Reboot Test Reboot the system immediately after applying patches/updates. Check the system logs to see if the dependency issue is logged again. Using the debug logs, determine exactly which dependency failed to start in time. This will help system administrators adjust service startup delays or systemd dependencies to ensure Docker waits for the required services before attempting to start.