How to Check a Dock Before Destruction

Overview

Docks don't just fail, there's always a root cause. Many times the "solution" to fixing a dock is to simply destroy it and replace it with a fresh and shiny new instance. To aid our understanding of the dock failure scenarios please follow this guide to get information about why the dock may have failed.

Memory / Inodes / Disk Usage

From the dock, run and record the output of the following:

• Memory usage: free -ght
• Disk usage: df -h
• Inodes: df -hi

Swarm + Weave Containers

Copy and record the results of the following command:

• sudo docker ps | grep swarm && sudo docker ps | grep weave

You should see exactly two containers.

Docker Logs

Download the logs from: /var/log/upstart/docker*

Dock Init Logs

Download the dock-init logs: /var/log/user-script-dock-init.log

Krain

Download the logs: /var/log/krain.log