使用 helm 部署应用 MySQL ¶
环境说明：k8s 集群中存在 storageclass:nfs-client
[root@k8smaster002 mysql]# kubectl get sc
NAME PROVISIONER RECLAIMPOLICY
nfs-client (default) k8s-sigs.io/nfs-subdir-external-provisioner Delete
helm 安装一个 mysql 应用： ¶
传参方式安装一个 mysql 应用： ¶
传参方式安装一个 mysql 应用
1、仓库中搜索 mysql
[root@k8smaster002 mysql]# helm search repo mysql
NAME CHART VERSION APP VERSION DESCRIPTION
prometheus-community/prometheus-mysql-exporter 2.5.1 v0.15.1 A Helm chart for prometheus mysql exporter with...
stable/mysql 1.6.9 5.7.30 DEPRECATED - Fast, reliable, scalable, and easy...
2、Helm Chart 的安装
[root@k8smaster002 mysql]# helm install stable/mysql --generate-name --set persistence.storageClass=nfs-client --set mysqlRootPassword=test123
3、部署过程输出的信息：
WARNING: This chart is deprecated
NAME: mysql-1712733475
LAST DEPLOYED: Wed Apr 10 15:18:01 2024
NAMESPACE: default
STATUS: deployed
REVISION: 1
NOTES:
MySQL can be accessed via port 3306 on the following DNS name from within your cluster:
mysql-1712733475.default.svc.cluster.local
To get your root password run:
MYSQL_ROOT_PASSWORD=$(kubectl get secret --namespace default mysql-1712733475 -o jsonpath="{.data.mysql-root-password}" | base64 --decode; echo)
To connect to your database:
1. Run an Ubuntu pod that you can use as a client:
kubectl run -i --tty ubuntu --image=ubuntu:16.04 --restart=Never -- bash -il
2. Install the mysql client:
$ apt-get update && apt-get install mysql-client -y
3. Connect using the mysql cli, then provide your password:
$ mysql -h mysql-1712733475 -p
To connect to your database directly from outside the K8s cluster:
MYSQL_HOST=127.0.0.1
MYSQL_PORT=3306
# Execute the following command to route the connection:
kubectl port-forward svc/mysql-1712733475 3306
mysql -h ${MYSQL_HOST} -P${MYSQL_PORT} -u root -p${MYSQL_ROOT_PASSWORD}
4、查看 helm 中安装了什么应用
...
[root@k8smaster002 mysql]# helm list
NAME NAMESPACE REVISION STATUS CHART APP VERSION
my-mysql default 1 CST deployed mysql-1.6.9 5.7.30
...
...
[root@k8smaster002 mysql]# kubectl get pods
NAME READY STATUS RESTARTS AGE
mysql-1712733475-58588bcf5c-87x4q 1/1 Running 0 6m42s
...
...
[root@k8smaster002 mysql]# kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS VOLUMEATTRIBUTESCLASS AGE
mysql-1712733475 Bound pvc-c0600437-f632-4a89-8f57-f35dc09f67e2 8Gi RWO nfs-client <unset> 7m50s
...
...
[root@k8smaster002 mysql]# kubectl get pv
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS
pvc-c0600437-f632-4a89-8f57-f35dc09f67e2 8Gi RWO Delete Bound default/mysql-1712733475 nfs-client
...
一个 chart 包是可以多次安装到同一个集群中的，每次安装都会产生一个 release, 每个 release 都可以独立管理和升级。
1、安装第二个 mysql
...
[root@k8smaster002 mysql]# helm install stable/mysql --generate-name --set persistence.storageClass=nfs-client --set mysqlRootPassword=test456
...
...
[root@k8smaster002 mysql]# helm list
NAME NAMESPACE REVISION STATUS CHART APP VERSION
mysql-1712733475 default 1 deployed mysql-1.6.9 5.7.30
mysql-1712735087 default 1 CST deployed mysql-1.6.9 5.7.30
...
...
[root@k8smaster002 mysql]# kubectl get pod
NAME READY STATUS RESTARTS AGE
mysql-1712733475-58588bcf5c-55r79 1/1 Running 0 6m
mysql-1712735087-5665bcc547-ncjkc 1/1 Running 0 26s
...
1、kubectl exec -it mysql-1712733475-58588bcf5c-55r79 -- mysql -uroot -ptest123
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 144
Server version: 5.7.30 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> create database mysql001;
Query OK, 1 row affected (0.02 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| mysql001 |
| performance_schema |
| sys |
+--------------------+
5 rows in set (0.00 sec)
1、kubectl exec -it mysql-1712735087-5665bcc547-ncjkc -- mysql -uroot -ptest456
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 113
Server version: 5.7.30 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 |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
4 rows in set (0.01 sec)
查看 chart 资源 ¶
1、查看 release=mysql-1712733475 的资源描述
[root@k8smaster002 mysql]# kubectl get all -l release=mysql-1712733475
NAME READY STATUS RESTARTS AGE
pod/mysql-1712733475-58588bcf5c-55r79 1/1 Running 0 17m
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/mysql-1712733475 ClusterIP 10.108.240.154 <none> 3306/TCP 38m
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/mysql-1712733475 1/1 1 1 38m
NAME DESIRED CURRENT READY AGE
replicaset.apps/mysql-1712733475-58588bcf5c 1 1 1 38m
2、我们也可以 helm show chart 命令来了解 MySQL 这个 chart 包的一些特性：
[root@k8smaster002 mysql]# helm show chart stable/mysql
apiVersion: v1
appVersion: 5.7.30
deprecated: true
description: DEPRECATED - Fast, reliable, scalable, and easy to use open-source relational
database system.
home: https://www.mysql.com/
icon: https://www.mysql.com/common/logos/logo-mysql-170x115.png
keywords:
- mysql
- database
- sql
name: mysql
sources:
- https://github.com/kubernetes/charts
- https://github.com/docker-library/mysql
version: 1.6.9
删除 Release ¶
如果需要删除这个 release，也很简单，只需要使用 helm uninstall或helm delete 命令即可：
1. 使用 uninstall 命令会从 Kubernetes 中删除 release，也会删除与 release 相关的所有 Kubernetes 资源以及 release 历史记录。
[root@k8smaster002 mysql]# helm uninstall mysql-1712733475
release "mysql-1712733475" uninstalled
[root@k8smaster002 mysql]# helm ls
NAME NAMESPACE REVISION UPDATED STATUS CHART APP VERSION
mysql-1712735087 default 1 2024-04-10 15:44:48.054667469 +0800 CST deployed mysql-1.6.9 5.7.30
2. 在删除的时候使用 --keep-history 参数，则会保留 release 的历史记录，该 release 的状态就是 UNINSTALLED
[root@k8smaster002 mysql]# helm uninstall mysql-1712735087 --keep-history
release "mysql-1712735087" uninstalled
[root@k8smaster002 mysql]# helm ls -a
NAME NAMESPACE REVISION UPDATED STATUS CHART APP VERSION
mysql-1712735087 default 1 2024-04-10 15:44:48.054667469 +0800 CST uninstalled mysql-1.6.9 5.7.30
# 状态为 uninstalled
3. 审查历史时甚至可以取消删除 release
`Usage: helm rollback <RELEASE> [REVISION] [flags]`
[root@k8smaster002 mysql]# helm rollback mysql-1712735087 1
Rollback was a success! Happy Helming!
[root@k8smaster002 mysql]# helm ls
NAME NAMESPACE REVISION UPDATED STATUS CHART APP VERSION
mysql-1712735087 default 2 2024-04-10 16:14:28.241929672 +0800 CST deployed mysql-1.6.9 5.7.30
# rollback 后，又回到 deployed 状态
定制参数部署应用 mysql 应用： ¶
传参方式安装一个 mysql 应用
1、上面我们都是直接使用的 helm install 命令安装的 chart 包，这种情况下只会使用 chart 的默认配置选项，但是更多的时候，是各种各样的需求，所以我们希望根据自己的需求来定制 chart 包的配置参数。
我们可以使用 `helm show values` 命令来查看一个 chart 包的所有可配置的参数选项：
[root@k8smaster002 mysql]# helm show values stable/mysql
......
......
上面的所有参数都是可以用自己的数据来覆盖的，可以在安装的时候通过 YAML 格式的文件来传递这些参数。
2、查看 Helm Chart 的帮助文档
[root@k8smaster002 mysql]# helm show chart stable/mysql
apiVersion: v1
appVersion: 5.7.30
deprecated: true
description: DEPRECATED - Fast, reliable, scalable, and easy to use open-source relational
database system.
home: https://www.mysql.com/
icon: https://www.mysql.com/common/logos/logo-mysql-170x115.png
keywords:
- mysql
- database
- sql
name: mysql
sources:
- https://github.com/kubernetes/charts
- https://github.com/docker-library/mysql
version: 1.6.9
3、查看 Helm Chart 的配置选项和默认值并重定向到一个文件 values.yaml 并修改 values.yaml 文件中 storageClass 与 mysqlRootPassword
[root@k8smaster002 mysql]# helm show values stable/mysql > values.yaml
mysqlDatabase: helm
persistence:
enabled: true # 没有存储卷情况下，改为false
storageClass: "nfs-client"
mysqlRootPassword: test123
4、安装的时候使用 -f values.yaml 安装应用并覆盖参数
[root@k8smaster002 mysql]# helm install my-mysql stable/mysql -f values.yaml
# 部署过程输出的信息：
WARNING: This chart is deprecated
NAME: my-mysql
LAST DEPLOYED: Wed Apr 10 14:54:43 2024
NAMESPACE: default
STATUS: deployed
REVISION: 1
NOTES:
MySQL can be accessed via port 3306 on the following DNS name from within your cluster:
my-mysql.default.svc.cluster.local
To get your root password run:
MYSQL_ROOT_PASSWORD=$(kubectl get secret --namespace default my-mysql -o jsonpath="{.data.mysql-root-password}" | base64 --decode; echo)
To connect to your database:
1. Run an Ubuntu pod that you can use as a client:
kubectl run -i --tty ubuntu --image=ubuntu:16.04 --restart=Never -- bash -il
2. Install the mysql client:
$ apt-get update && apt-get install mysql-client -y
3. Connect using the mysql cli, then provide your password:
$ mysql -h my-mysql -p
To connect to your database directly from outside the K8s cluster:
MYSQL_HOST=127.0.0.1
MYSQL_PORT=3306
# Execute the following command to route the connection:
kubectl port-forward svc/my-mysql 3306
mysql -h ${MYSQL_HOST} -P${MYSQL_PORT} -u root -p${MYSQL_ROOT_PASSWORD}
5、查看 helm 中安装了什么应用
[root@k8smaster002 mysql]# helm list
NAME NAMESPACE REVISION STATUS CHART APP VERSION
my-mysql default 1 CST deployed mysql-1.6.9 5.7.30
6、查看部署的相关资源
[root@k8smaster002 mysql]# kubectl get all -l release=my-mysql -owide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/my-mysql-b6999b8b5-vsqlk 1/1 Running 0 2m36s 10.244.214.72 linuxnbg <none> <none>
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
service/my-mysql ClusterIP 10.108.247.193 <none> 3306/TCP 2m36s app=my-mysql
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
deployment.apps/my-mysql 1/1 1 1 2m36s my-mysql mysql:5.7.30 app=my-mysql,release=my-mysql
NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR
replicaset.apps/my-mysql-b6999b8b5 1 1 1 2m36s my-mysql mysql:5.7.30 app=my-mysql,pod-template-hash=b6999b8b5,release=my-mysql
安装 mysql 客户端并连接测试 ¶
1、部署 mariadb
yum install mariadb -y
2、查看 pod IP 地址 连接 mysql
[root@k8smaster002 mysql]# kubectl get pods -o wide -l release=my-mysql
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
my-mysql-b6999b8b5-vsqlk 1/1 Running 0 14m 10.244.214.72 linuxnbg <none> <none>
[root@k8smaster002 mysql]# mysql -h 10.244.214.72 -u root -ptest123 -e "show databases;"
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
5、查看 service IP 连接 mysql
[root@k8smaster002 mysql]# kubectl get svc -o wide -l release=my-mysql
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
my-mysql ClusterIP 10.108.247.193 <none> 3306/TCP 19m app=my-mysql
[root@k8smaster002 mysql]# mysql -h 10.108.247.193 -u root -ptest123 -e "show databases;"
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
升级和回滚 ¶
当新版本的 chart 包发布的时候，或者当你要更改 release 的配置的时候，你可以使用 helm upgrade 命令来操作。升级需要一个现有的 release，并根据提供的信息对其进行升级。因为 Kubernetes charts 可能很大而且很复杂，Helm 会尝试以最小的侵入性进行升级，它只会更新自上一版本以来发生的变化：
升级 mysql ¶
1. 升级 mysql
1. 升级前查看版本
[root@k8smaster002 ~]# mysql -h 10.108.247.193 -u root -ptest123 -e "select version()"
+-----------+
| version() |
+-----------+
| 5.7.30 |
+-----------+
[root@k8smaster002 ~]# kubectl get deployment my-mysql -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
my-mysql 1/1 1 1 75m my-mysql mysql:5.7.30 app=my-mysql,release=my-mysql
2. 修改配置并升级加一个 --set imageTag=5.7.31 参数设置为5.7.31版本
[root@k8smaster002 mysql]# helm upgrade my-mysql -f values.yaml --set imageTag=5.7.31 stable/mysql
WARNING: This chart is deprecated
Release "my-mysql" has been upgraded. Happy Helming!
# 升级过程中的输出：
NAME: my-mysql
LAST DEPLOYED: Wed Apr 10 17:55:08 2024
NAMESPACE: default
STATUS: deployed
REVISION: 2
NOTES:
MySQL can be accessed via port 3306 on the following DNS name from within your cluster:
my-mysql.default.svc.cluster.local
To get your root password run:
MYSQL_ROOT_PASSWORD=$(kubectl get secret --namespace default my-mysql -o jsonpath="{.data.mysql-root-password}" | base64 --decode; echo)
To connect to your database:
1. Run an Ubuntu pod that you can use as a client:
kubectl run -i --tty ubuntu --image=ubuntu:16.04 --restart=Never -- bash -il
2. Install the mysql client:
$ apt-get update && apt-get install mysql-client -y
3. Connect using the mysql cli, then provide your password:
$ mysql -h my-mysql -p
To connect to your database directly from outside the K8s cluster:
MYSQL_HOST=127.0.0.1
MYSQL_PORT=3306
# Execute the following command to route the connection:
kubectl port-forward svc/my-mysql 3306
mysql -h ${MYSQL_HOST} -P${MYSQL_PORT} -u root -p${MYSQL_ROOT_PASSWORD}
3. 升级后确认版本是否为 5.7.31 版本
[root@k8smaster002 mysql]# kubectl get deployment my-mysql -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
my-mysql 1/1 1 1 80m my-mysql mysql:5.7.31 app=my-mysql,release=my-mysql
[root@k8smaster002 mysql]# mysql -h 10.108.247.193 -u root -ptest123 -e "select version()"
+-----------+
| version() |
+-----------+
| 5.7.31 |
+-----------+
回滚 mysql ¶
1. 回滚 mysql
1. 查看历史版本
[root@k8smaster002 mysql]# helm history my-mysql
REVISION UPDATED STATUS CHART APP VERSION DESCRIPTION
1 Wed Apr 10 16:36:56 2024 superseded mysql-1.6.9 5.7.30 Install complete
2 Wed Apr 10 17:55:08 2024 deployed mysql-1.6.9 5.7.30 Upgrade complete
2. 使用 rollback mysql 来回滚版本
[root@k8smaster002 mysql]# helm rollback my-mysql 1
Rollback was a success! Happy Helming!
3. 查看回滚之后的版本
[root@k8smaster002 mysql]# kubectl get deployment my-mysql -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
my-mysql 1/1 1 1 116m my-mysql mysql:5.7.30 app=my-mysql,release=my-mysql
4. 使用 rollback mysql 来回滚版本
[root@k8smaster002 mysql]# helm history my-mysql
REVISION UPDATED STATUS CHART APP VERSION DESCRIPTION
1 Wed Apr 10 16:36:56 2024 superseded mysql-1.6.9 5.7.30 Install complete
2 Wed Apr 10 17:55:08 2024 superseded mysql-1.6.9 5.7.30 Upgrade complete
3 Wed Apr 10 18:32:38 2024 deployed mysql-1.6.9 5.7.30 Rollback to 1
更多安装方式 ¶
和yum命令类似
- chart 仓库
- 本地 chart 压缩包
[root@k8smaster002 mysql]# helm pull stable/mysql
[root@k8smaster002 mysql]# ls mysql-1.6.9.tgz
mysql-1.6.9.tgz
[root@k8smaster002 mysql]# helm install mysql2 mysql-1.6.9.tgz
- 在线的 URL（helm install fool https://example.com/charts/foo-1.2.3.tgz）