Deploy Multiple Sets of TiDB Operator

This document describes how to deploy multiple sets of TiDB Operator to manage different TiDB clusters.

Note:
Currently, you can only deploy multiple tidb-controller-managers and tidb-schedulers.
If you have deployed multiple sets of TiDB Operator and only some of them enable Advanced StatefulSet, the same TidbCluster Custom Resource (CR) cannot be switched among these TiDB Operator.
This feature is supported since v1.1.10.

To support deploying multiple sets of TiDB Operator, the following parameters are added to the values.yaml file in the tidb-operator chart:

appendReleaseSuffix
If this parameter is set to true, when you deploy TiDB Operator, the Helm chart automatically adds a suffix (-{{ .Release.Name }}) to the name of resources related to tidb-controller-manager and tidb-scheduler.
For example, if you execute helm install canary pingcap/tidb-operator ..., the name of the tidb-controller-manager deployment is tidb-controller-manager-canary.
If you need to deploy multiple sets of TiDB Operator, set this parameter to true.
Default value: false.
controllerManager.create
Controls whether to create tidb-controller-manager.
Default value: true.
controllerManager.selector
Sets the -selector parameter for tidb-controller-manager. The parameter is used to filter the CRs controlled by tidb-controller-manager according to the CR labels. If multiple selectors exist, the selectors are in and relationship.
Default value: [] (tidb-controller-manager controls all CRs).
Example:
```
selector:
- canary-release=v1
- k1==v1
- k2!=v2
```
scheduler.create
Controls whether to create tidb-scheduler.
Default value: true.

Deploy

Deploy the first TiDB Operator.
Refer to Deploy TiDB Operator to deploy the first TiDB Operator. Add the following configuration in the values.yaml:
```
controllerManager:
  selector:
  - user=dev
```
Deploy the TiDB cluster.
1. Refer to Configure the TiDB Cluster to configure the TidbCluster CR, and configure labels to match the selector set in the last step. For example:
```
apiVersion: pingcap.com/v1alpha1
kind: TidbCluster
metadata:
  name: basic1
  labels:
    user: dev
spec:
  ...
```
  If labels is not set when you deploy the TiDB cluster, you can configure labels by running the following command:
```
kubectl -n ${namespace} label tidbcluster ${cluster_name} user=dev
```
2. Refer to Deploy TiDB in General Kubernetes to deploy the TiDB cluster. Confirm that each component in the cluster is started normally.
Deploy the second TiDB Operator.
Refer to Deploy TiDB Operator to deploy the second TiDB Operator without tidb-scheduler. Add the following configuration in the values.yaml file, and deploy the second TiDB Operator (without tidb-scheduler) in a different namespace (such as tidb-admin-qa):
```
controllerManager:
  selector:
  - user=qa
appendReleaseSuffix: true
scheduler:
  create: false
```
Note:
- It is recommended to deploy the new TiDB Operator in a separate namespace.
- Set appendReleaseSuffix to true.
- If you configure scheduler.create: true, a tidb-scheduler named {{ .scheduler.schedulerName }}-{{.Release.Name}} is created. To use this tidb-scheduler, you need to configure spec.schedulerName in the TidbCluster CR to the name of this scheduler.
Deploy the TiDB cluster.
1. Refer to Configure the TiDB Cluster to configure the TidbCluster CR, and configure labels to match the selector set in the last step. For example:
```
apiVersion: pingcap.com/v1alpha1
kind: TidbCluster
metadata:
  name: basic2
  labels:
    user: qa
spec:
  ...
```
  If labels is not set when you deploy the TiDB cluster, you can configure labels by running the following command:
```
kubectl -n ${namespace} label tidbcluster ${cluster_name} user=qa
```
2. Refer to Deploy TiDB in General Kubernetes to deploy the TiDB cluster. Confirm that each component in the cluster is started normally.

View the logs of the two sets of TiDB Operator, and confirm that each TiDB Operator manages the TiDB cluster that matches the corresponding selectors.

For example:

View the log of tidb-controller-manager of the first TiDB Operator:

kubectl -n tidb-admin logs tidb-controller-manager-55b887bdc9-lzdwv

Output

... I0113 02:50:13.195779       1 main.go:69] FLAG: --selector="user=dev" ... I0113 02:50:32.409378       1 tidbcluster_control.go:69] TidbCluster: [tidb-cluster-1/basic1] updated successfully I0113 02:50:32.773635       1 tidbcluster_control.go:69] TidbCluster: [tidb-cluster-1/basic1] updated successfully I0113 02:51:00.294241       1 tidbcluster_control.go:69] TidbCluster: [tidb-cluster-1/basic1] updated successfully

View the log of tidb-controller-manager of the second TiDB Operator:

kubectl -n tidb-admin-qa logs tidb-controller-manager-qa-5dfcd7f9-vll4c

Output

... I0113 02:50:13.195779       1 main.go:69] FLAG: --selector="user=qa" ... I0113 03:38:43.859387       1 tidbcluster_control.go:69] TidbCluster: [tidb-cluster-2/basic2] updated successfully I0113 03:38:45.060028       1 tidbcluster_control.go:69] TidbCluster: [tidb-cluster-2/basic2] updated successfully I0113 03:38:46.261045       1 tidbcluster_control.go:69] TidbCluster: [tidb-cluster-2/basic2] updated successfully

By comparing the logs of the two sets of TiDB Operator, you can confirm that the first TiDB Operator only manages the tidb-cluster-1/basic1 cluster, and the second TiDB Operator only manages the tidb-cluster-2/basic2 cluster.

Deploy Multiple Sets of TiDB Operator

Related parameters

Deploy