Get a Charmed MySQL up and running
This is part of the Charmed MySQL Tutorial. Please refer to this page for more information and the overview of the content.
Deploy Charmed MySQL K8s
Info: To deploy Charmed MySQL K8s, all you need to do is run the following command, which will fetch the charm from Charmhub and deploy it to your model:
juju deploy mysql-k8s --channel 8.0 --trust
Note: --trust is required to create some K8s resources.
Juju will now fetch Charmed MySQL K8s and begin deploying it to the Microk8s Kubernetes. This process can take several minutes depending on how provisioned (RAM, CPU, etc) your machine is. You can track the progress by running:
juju status --watch 1s
This command is useful for checking the status of Charmed MySQL K8s and gathering information about the machines hosting Charmed MySQL. Some of the helpful information it displays include IP addresses, ports, state, etc. The command updates the status of Charmed MySQL K8s every second and as the application starts you can watch the status and messages of Charmed MySQL K8s change. Wait until the application is ready - when it is ready, juju status will show:
Model Controller Cloud/Region Version SLA Timestamp
tutorial overlord microk8s/localhost 2.9.44 unsupported 22:33:45+01:00
App Version Status Scale Charm Channel Rev Address Exposed Message
mysql-k8s 8.0.31 active 1 mysql-k8s 8.0/stable 36 10.152.183.234 no Unit is ready: Mode: RW
Unit Workload Agent Address Ports Message
mysql-k8s/0* active idle 10.1.84.74 Unit is ready: Mode: RW
To exit the screen with juju status --watch 1s, enter Ctrl+c.
If you want to further inspect juju logs, can watch for logs with juju debug-log.
More info on logging at juju logs.
Access MySQL
! Disclaimer: this part of the tutorial accesses MySQL via the
rootuser. Do not directly interface with the root user in a production environment. In a production environment always create a separate user using Data Integrator and connect to MySQL with that user instead. Later in the section covering Relations we will cover how to access MySQL without the root user.
The first action most users take after installing MySQL is accessing MySQL. The easiest way to do this is via the MySQL Command-Line Client mysql. Connecting to the database requires that you know the values for host, username and password. To retrieve the necessary fields please run Charmed MySQL K8s action get-password:
juju run-action mysql-k8s/leader get-password --wait
Running the command should output:
unit-mysql-k8s-0:
UnitId: mysql-k8s/0
id: "2"
results:
password: sQI3Ojih7uL5UC4J1D9Xuqgx
username: root
status: completed
timing:
completed: 2023-02-15 21:35:56 +0000 UTC
enqueued: 2023-02-15 21:35:55 +0000 UTC
started: 2023-02-15 21:35:55 +0000 UTC
Note: to request a password for a different user, use an option username:
juju run-action mysql-k8s/leader get-password username=myuser --wait
The host’s IP address can be found with juju status (the unit hosting the MySQL K8s application):
...
Unit Workload Agent Address Ports Message
mysql-k8s/0* active idle 10.1.84.74 Unit is ready: Mode: RW
...
To access the units hosting Charmed MySQL K8s use:
mysql -h 10.1.84.74 -uroot -p<password>
Note: if at any point you’d like to leave the unit hosting Charmed MySQL, enter Ctrl+d or type exit.
Inside MySQL list DBs available on the host show databases:
> mysql -h 10.1.84.74 -uroot -psQI3Ojih7uL5UC4J1D9Xuqgx
Server version: 8.0.31-0ubuntu0.22.04.1 (Ubuntu)
...
mysql> show databases;
+-------------------------------+
| Database |
+-------------------------------+
| information_schema |
| mysql |
| mysql_innodb_cluster_metadata |
| performance_schema |
| sys |
+-------------------------------+
5 rows in set (0.01 sec)
Note: if at any point you’d like to leave the MySQL client, enter Ctrl+d or type exit.
You can now interact with MySQL directly using any MySQL Queries. For example entering SELECT VERSION(), CURRENT_DATE; should output something like:
mysql> SELECT VERSION(), CURRENT_DATE;
+-------------------------+--------------+
| VERSION() | CURRENT_DATE |
+-------------------------+--------------+
| 8.0.31-0ubuntu0.22.04.1 | 2023-02-15 |
+-------------------------+--------------+
1 row in set (0.00 sec)
Feel free to test out any other MySQL queries. When you’re ready to leave the MySQL shell you can just type exit. Now you will be in your original shell where you first started the tutorial; here you can interact with Juju and Microk8s.