Setting up worldPing with Grafana running in docker

You would like to test worldPing (https://worldping.raintank.io/worldping/) in your local environment for evaluation purposes.

  • Install Grafana with docker as described here (https://grafana.com/docs/grafana/latest/installation/docker/) and give it a name (ie grafana)
  • Login to the grafana container and install the worldPing plugin:
  • Exit from the container and stop and start it
  • Login to your grafana installation on the browser (localhost:3000) and go to the section for the plugins to find worldPing
  • To be able to enable it you will need an API key from Grafana Cloud, so create a free account (https://grafana.com/signup/starter/connect-account)
  • Create an API key (Security – API Keys – Add API Key)
  • Go back to Grafana web UI and add the API key so you can enable the worldPing. Add an endpoint to check and select the services to check (DNS, Ping, HTTP, HTTPS)
  • Leave it running for a few minutes and check the dashboards afterwards.
  • Remember to Disable if you want to go back to it again in the near future, or Destroy the endpoint if you do not need it anymore.

Cannot create container for service xxx: invalid mode: /path/to/volume/

Problem

You are trying to use docker-compose to get some services up with docker but you see an error like the following:

Solution

This is more than likely caused by a typo in your yml file, so go back and check carefully for any typos and correct them.

ERROR: Couldn’t connect to Docker daemon at http+docker://localunixsocket – is it running?

Problem

Using docker-compose up (or build), displays the following error message (even though the same command used to work previously):

Solution

This is quite possible caused by permissions issue, as one of the folders files that docker is trying to use is owned by a different user/group from the one trying to use the docker-compose commands. Try to find the file/folder with the different permissions and change it to your user name and group, or use change the files by using something like:

Find the IP Address of a running Docker container

Problem

You would like to know the IP Address of a running Docker container.

Solution

Use the following to find out the IP Address by replacing the container_name with the actual container name:

Connection refused when using http monitoring with blackbox_exporter and prometheus

Problem

You are trying to set up http endpoint monitoring with prometheus and blackbox_exporter by specifying something like the following:

but you are getting the error (in prometheus targets) that connection was refused.

Solution

First specify the ip protocol as ip4 if you are not using ip6 like:

And then make sure that you use the container IP address in the replacement field if you have started blackbox_exporter as a docker container (tip taken from here), which you can find by looking for the container IP address (docker inspect blackbox_exporter | grep IPAddress).

So your prometheus configuration should look like the following (different replacement IP):

Docker Cloud moving one node from one account to another

Problem

You have used ‘Bring your own node’ to use a server with one account, but you want to change the account and move the node to the new one.

Solution

Use your old account to terminate the node or login to the server and use the following to stop the running dockercloud-agent:

Go to the Docker Cloud web ui interface, and use the 'Bring your own node'. Copy the token that appears after the sudo -H sh -s on the popup window.

On the server update the token with the one from the new account that you just copied, by running the following:

And now restart the dockercloud-agent on the server:

You should now be able to see 'Node xxxx detected' on the Docker Cloud web ui after a couple of minutes.

FATAL -> Failed to fork – Digital Ocean – Debian – Docker

Problem

When you are trying to install a package inside a debian Docker container you get the following error message:

Solution

This is an indication of ‘out of memory’ so add a swap partition if it does not exist, on the host with the following:

(Thanks Valent)

Docker – Debian – Kernel panick – Automatic restart

Problem

You have a remote server (Debian) running some Docker containers and you want to make sure that they all restart in the event of a kernel panick.

solution

  • Add an automatic restart after a kernel panick by running:

  • Emulate a kernel panick by running the following (SysRq more info here :

  • Check that the containers have restarted again with docker ps (NOTE: the containers should have been enabled to autorestart)