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.

Terraform Cloud – error when trying to initialize

Problem

You would like to start using Terraform Cloud and when trying to initialize it with the new remote backend (app.terraform.io), you get the following error:

Error: Required token could not be found

Make sure you configured a credentials block for app.terraform.io in your CLI
Config File.

Solution

Follow the instructions here https://www.terraform.io/docs/cloud/free/index.html and create a file ~/.terraformrc (in linux) with an API token.

Getting the slug name for Digital Ocean’s images with doctl

Problem

You would like to get a list of the available images in Digital Ocean, in order to be able to use them in creating your Terraform IAC script.

Solution

By installing the command line tool doctl, (instructions here), according to the documentation (after authenticating) you can run:

But the available images are not listed. In order to be list all the images you have to add the –public option (as described here) :

Stopping a blocking query in postgresql

Problem

You run a query in PostgreSQL that takes a lot of time to finish (maybe because of an error) and you want to stop/kill it as it is blocking other queries in db.

Solution

You will need to find the pid for the query, either by using a GUI program like Pgadmin or by issuing the following to an SQL prompt:

make a note of the pid of the query that you want to stop/kill and issue the following:

Some useful docker commands

Having started to use docker recently, some of the commands that are needed are a bit difficult to remember. I’m sure that this will change the more that I use it, but as a quick reminder/look up for this initial phase, I’m just going to list some of them here.

List current images:

List currrent running containers:

Saving the state of a container by using the id from above command:

Starting a container with port forwarding:

Sharing a directory from the host system (/home/user/Prog) inside the container (Prog):