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Running Docker Commands with Administration Scripts
Video Lecture
Description
Note
This lesson was from a previous version of my course, which I've now made this video available to view for free.
Running Docker Commands with Zabbix Administration Scripts
In this video, I demonstrate how to use administration scripts to manage docker containers.
During the configuration I encounter several issues in which I solve them all.
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It's important that the agent, proxy or server process that you want to use to run the script, needs
EnableRemoteCommands=1set in its config file. Then restart the agent, proxy or server service. The specific details of enabled remote commands depend on which version of the agent you are running, and have been covered several times in the previous sections. -
If the command you execute needs privileged permissions, then run it with the sudo prefix.
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To allow the Zabbix user to use the sudo prefix, add a new line to the sudoers file.
sudo visudo
Add
zabbix ALL=(ALL) NOPASSWD: /usr/bin/docker
With these 3 things, I was able to execute docker commands on my host using the administration scripts option.
Those commands were,
sudo docker ps -a
sudo docker stats -a --no-stream
sudo docker stop nginx2
sudo docker start nginx2
Example Images
To install docker on Ubuntu 20.04.
sudo apt install docker.io
To list any docker containers,
sudo docker ps -a
To list any docker images that were downloaded to create the containers,
sudo docker images
The example containers I created used in the video were from https://hub.docker.com/r/nginxdemos/hello/
sudo docker run -P -d --name nginx1 nginxdemos/hello
sudo docker run -P -d --name nginx1 nginxdemos/hello
sudo docker run -P -d --name nginx1 nginxdemos/hello
After experimenting with docker containers and images, and you no longer want them, you can clean up your system and delete them using these commands.
sudo docker rm -f $(sudo docker ps -a -q)
sudo docker rmi -f $(sudo docker images -q)
Troubleshooting
Ensure EnableRemoteCommands=1 is set in your agent/proxy config. And you have restarted your agent/proxy after making the change.
If you get the error,
Unsupported item key.
Cannot execute script
It could be many things. It may also be because your agent is connected to the server with only Active checks. The server is unable to find your agent, possibly due to it being on a different network with no firewall rule configuration to forward the request from the server. If your agent is behind a firewall, and is using a Zabbix Proxy, then you won't need to configure the firewall as long as your Proxy is also running in Active mode (default).