Helm V2 迁移到 V3

Helm V3 与 V2 版本架构变化较大,数据迁移比较麻烦,官方提供了一个名为 helm-2to3 的插件来简化迁移工作,本文将介绍如何利用此插件迁移 Helm V2 到 V3 版本。这里前提是 Helm V3 已安装,安装方法请参考 这里

安装 2to3 插件

一键安装:

$ helm3 plugin install https://github.com/helm/helm-2to3
Downloading and installing helm-2to3 v0.1.1 ...
https://github.com/helm/helm-2to3/releases/download/v0.1.1/helm-2to3_0.1.1_linux_amd64.tar.gz
Installed plugin: 2to3

检查插件是否安装成功:

$ helm3 plugin list
NAME VERSION DESCRIPTION
2to3 0.1.1 migrate Helm v2 configuration and releases in-place to Helm v3

迁移 Helm V2 配置

$ helm3 2to3 move config
[Helm 2] Home directory: /root/.helm
[Helm 3] Config directory: /root/.config/helm
[Helm 3] Data directory: /root/.local/share/helm
[Helm 3] Create config folder "/root/.config/helm" .
[Helm 3] Config folder "/root/.config/helm" created.
[Helm 2] repositories file "/root/.helm/repository/repositories.yaml" will copy to [Helm 3] config folder "/root/.config/helm/repositories.yaml" .
[Helm 2] repositories file "/root/.helm/repository/repositories.yaml" copied successfully to [Helm 3] config folder "/root/.config/helm/repositories.yaml" .
[Helm 3] Create data folder "/root/.local/share/helm" .
[Helm 3] data folder "/root/.local/share/helm" created.
[Helm 2] plugins "/root/.helm/plugins" will copy to [Helm 3] data folder "/root/.local/share/helm/plugins" .
[Helm 2] plugins "/root/.helm/plugins" copied successfully to [Helm 3] data folder "/root/.local/share/helm/plugins" .
[Helm 2] starters "/root/.helm/starters" will copy to [Helm 3] data folder "/root/.local/share/helm/starters" .
[Helm 2] starters "/root/.helm/starters" copied successfully to [Helm 3] data folder "/root/.local/share/helm/starters" .

上面的操作主要是迁移:

  • Chart 仓库

  • Helm 插件

  • Chart starters

检查下 repo 和 plugin:

$ helm3 repo list
NAME URL
stable https://kubernetes-charts.storage.googleapis.com
local http://127.0.0.1:8879/charts
$
$
$ helm3 plugin list
NAME VERSION DESCRIPTION
2to3 0.1.1 migrate Helm v2 configuration and releases in-place to Helm v3
push 0.1.1 Push chart package to TencentHub

迁移 Heml V2 Release

已经用 Helm V2 部署的应用也可以使用 2to3convert 子命令迁移到 V3,先看下有哪些选项:

$ helm3 2to3 convert --help
migrate Helm v2 release in-place to Helm v3
Usage:
2to3 convert [flags] RELEASE
Flags:
--delete-v2-releases v2 releases are deleted after migration. By default, the v2 releases are retained
--dry-run simulate a convert
-h, --help help for convert
-l, --label string label to select tiller resources by (default "OWNER=TILLER")
-s, --release-storage string v2 release storage type/object. It can be 'secrets' or 'configmaps'. This is only used with the 'tiller-out-cluster' flag (default "secrets")
-t, --tiller-ns string namespace of Tiller (default "kube-system")
--tiller-out-cluster when Tiller is not running in the cluster e.g. Tillerless
  • --tiller-out-cluster: 如果你的 Helm V2 是 tiller 在集群外面 (tillerless) 的安装方式,请带上这个参数

  • --dry-run: 模拟迁移但不做真实迁移操作,建议每次迁移都先带上这个参数测试下效果,没问题的话再去掉这个参数做真实迁移

  • --tiller-ns: 通常 tiller 如果部署在集群中,并且不在 kube-system 命名空间才指定

看下目前有哪些 helm v2 的 release:

$ helm ls
NAME REVISION UPDATED STATUS CHART APP VERSION NAMESPACE
redis 1 Mon Sep 16 14:46:58 2019 DEPLOYED redis-9.1.3 5.0.5 default

选一个用 --dry-run 试下效果:

$ helm3 2to3 convert redis --dry-run
NOTE: This is in dry-run mode, the following actions will not be executed.
Run without --dry-run to take the actions described below:
Release "redis" will be converted from Helm 2 to Helm 3.
[Helm 3] Release "redis" will be created.
[Helm 3] ReleaseVersion "redis.v1" will be created.

没有报错,去掉 --dry-run 执行迁移:

$ helm3 2to3 convert redis
Release "redis" will be converted from Helm 2 to Helm 3.
[Helm 3] Release "redis" will be created.
[Helm 3] ReleaseVersion "redis.v1" will be created.
[Helm 3] ReleaseVersion "redis.v1" created.
[Helm 3] Release "redis" created.
Release "redis" was converted successfully from Helm 2 to Helm 3. Note: the v2 releases still remain and should be removed to avoid conflicts with the migrated v3 releases.

检查迁移结果:

$ helm ls
NAME REVISION UPDATED STATUS CHART APP VERSION NAMESPACE
redis 1 Mon Sep 16 14:46:58 2019 DEPLOYED redis-9.1.3 5.0.5 default
$
$
$ helm3 ls -a
NAME NAMESPACE REVISION UPDATED STATUS CHART
redis default 1 2019-09-16 06:46:58.541391356 +0000 UTC deployed redis-9.1.3
  • helm 3 的 release 区分了命名空间,带上 -a 参数展示所有命名空间的 release

参考资料