Container Logging

Container Logging

  • Last updated 6/2024
  • English
  • Published 2025-04-24
  • Location Online
  • Duration 1h 0m
What you'll learn

For the last six months, the Acme Anvil Corporation has been migrating some of their bare metal infrastructure to Docker containers. After the initial implementation, the team has decided to implement a better logging strategy by using a centralized syslog server. You have been tasked with configuring syslog on one of the Docker instances. Next, you will configure Docker to use syslog instead of the JSON file log. Finally, you will test the configuration by spinning up two containers to test logging with syslog and a JSON file.

This course includes:

Table of Contents

  1. Challenge

    Configure syslog.

    You will need to open rsyslog.conf and make a few changes:

    vim /etc/rsyslog.conf
    

    Uncomment the two UDP syslog receptions:

    #$ModLoad imudp
    #$UDPServerRun 514
    

    to

    $ModLoad imudp
    $UDPServerRun 514
    
  2. Challenge

    Configure Docker to use syslog.

    Create the daemon.json file.

    mkdir /etc/docker
    vim /etc/docker/daemon.json
    

    Add the following content.

    {
    "log-driver": "syslog",
    "log-opts": {
    "syslog-address": "udp://PRIVATE_IP:514"
    }
    }
    
  3. Challenge

    Create a container using syslog.

    Enable and start the Dockere service.

    sudo systemctl enable docker
    sudo systemctl start docker
    

    Create a container called syslog-logging using the httpd image.

    docker container run -d --name syslog-logging --log-driver none httpd
    
  4. Challenge

    Create a container using a JSON file.

    Create a container that uses the JSON file for logging.

    docker container run -d --name json-logging --log-driver json-file httpd
    
  5. Challenge

    Verify that the `syslog-logging` container is sending its logs to syslog.

    Make sure that the syslog-logging container is logging to syslog by checking the message log file:

    tail /var/log/messages
    
  6. Challenge

    Verify that the `json-logging` container is sending its logs to the JSON file.

    Execute docker logs for the json-logging container.

    docker logs json-logging