Vitess Operator for Kubernetes
PlanetScale provides a Vitess Operator for Kubernetes, released under the Apache 2.0 license. The following steps show how to get started using Minikube:
Prerequisites #
Before we get started, let’s get a few pre-requisites out of the way:
Install Docker Engine locally.
Install Minikube and start a Minikube engine:
minikube start --kubernetes-version=v1.25.8 --cpus=4 --memory=11000 --disk-size=32g
Allocating less memory than specified will cause crashes in subsequent steps and break the processInstall kubectl and ensure it is in your
PATH
.Install the MySQL client locally.
Install vtctldclient locally.
Install the Operator #
Change to the operator example directory:
git clone https://github.com/vitessio/vitess
git checkout release-18.0
cd vitess/examples/operator
Install the operator:
kubectl apply -f operator.yaml
Bring up an initial cluster #
In this directory, you will see a group of yaml files. The first digit of each file name indicates the phase of example. The next two digits indicate the order in which to execute them. For example, 101_initial_cluster.yaml
is the first file of the first phase. We shall execute that now:
kubectl apply -f 101_initial_cluster.yaml
Verify cluster #
You can check the state of your cluster with kubectl get pods
. After a few minutes, it should show that all pods are in the status of running:
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
example-commerce-x-x-zone1-vtorc-c13ef6ff-5db4c77865-l96xq 1/1 Running 2 (2m49s ago) 5m16s
example-etcd-faf13de3-1 1/1 Running 0 5m17s
example-etcd-faf13de3-2 1/1 Running 0 5m17s
example-etcd-faf13de3-3 1/1 Running 0 5m17s
example-vttablet-zone1-2469782763-bfadd780 3/3 Running 1 (2m43s ago) 5m16s
example-vttablet-zone1-2548885007-46a852d0 3/3 Running 1 (2m47s ago) 5m16s
example-zone1-vtadmin-c03d7eae-7c6f6c98f8-f4f5z 2/2 Running 0 5m17s
example-zone1-vtctld-1d4dcad0-57b9d7bc4b-2tnqd 1/1 Running 2 (2m53s ago) 5m17s
example-zone1-vtgate-bc6cde92-7d445d676-x6npk 1/1 Running 2 (3m ago) 5m17s
vitess-operator-5f47c6c45d-bgqp2 1/1 Running 0 6m52s
Setup Port-forward #
kubectl
does not automatically terminate a port-forward as the pod disappears due to apply/upgrade operations. You will need to manually restart the port-forward.For ease-of-use, Vitess provides a script to port-forward from Kubernetes to your local machine. This script also recommends setting up aliases for mysql
and vtctldclient
:
./pf.sh &
alias vtctldclient="vtctldclient --server=localhost:15999"
alias mysql="mysql -h 127.0.0.1 -P 15306 -u user"
Setting up aliases changes mysql
to always connect to Vitess for your current session. To revert this, type unalias mysql && unalias vtctldclient
or close your session.
Once the port-forward starts running, the VTAdmin UI will be available at http://localhost:14000/
Create Schema #
Load our initial schema:
vtctldclient ApplySchema --sql-file="create_commerce_schema.sql" commerce
vtctldclient ApplyVSchema --vschema-file="vschema_commerce_initial.json" commerce
Connect to your cluster #
You should now be able to connect to the VTGate Server in your cluster with the MySQL client:
~/vitess/examples/operator$ mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 8.0.30-Vitess MySQL Community Server (GPL)
Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| commerce |
| information_schema |
| mysql |
| sys |
| performance_schema |
+--------------------+
5 rows in set (0.01 sec)
mysql>
Summary #
In this example, we deployed a single unsharded keyspace named commerce
. Unsharded keyspaces have a single shard named 0
. The following schema reflects a common ecommerce scenario that was created by the script:
create table product(
sku varbinary(128),
description varbinary(128),
price bigint,
primary key(sku)
);
create table customer(
customer_id bigint not null auto_increment,
email varbinary(128),
primary key(customer_id)
);
create table corder(
order_id bigint not null auto_increment,
customer_id bigint,
sku varbinary(128),
price bigint,
primary key(order_id)
);
The schema has been simplified to include only those fields that are significant to the example:
- The
product
table contains the product information for all of the products. - The
customer
table has acustomer_id
that has anauto_increment
. A typical customer table would have a lot more columns, and sometimes additional detail tables. - The
corder
table (named so becauseorder
is an SQL reserved word) has anorder_id
auto-increment column. It also has foreign keys intocustomer(customer_id)
andproduct(sku)
.
Common Issues and Solutions #
Issue: Starting Minikube produces the following error:
The "docker" driver should not be used with root privileges. If you wish to continue as root, use --force.
If you are running minikube within a VM, consider using --driver=none:
https://minikube.sigs.k8s.io/docs/reference/drivers/none
Exiting due to to DRV_AS_ROOT: The "docker" driver should not be used with root privileges.
Solution: Create a new user and add it to your docker group.
Next Steps #
You can now proceed with MoveTables.
Or alternatively, if you would like to teardown your example:
kubectl delete -f 101_initial_cluster.yaml
Congratulations on completing this exercise!