Configure cluster parameters

This guide shows how to configure cluster parameters.

For Pulsar, there are 3 types of parameters:

1. Environment parameters, such as GC-related parameters, PULSAR_MEM, and PULSAR_GC, changes will apply to all components;
2. Configuration parameters, such as zookeeper or bookies.conf configuration files, can be changed through env and changes restart the pod;
3. Dynamic parameters, such as configuration files in brokers.conf, broker supports two types of change modes: a. Parameter change requires a restart, such as zookeeperSessionExpiredPolicy; b. For parameters that support dynamic parameters, you can obtain a list of all dynamic parameters with pulsar-admin brokers list-dynamic-config.

note

pulsar-admin is a management tool built in the Pulsar cluster. You can log in to the corresponding pod with kubectl exec -it <pod-name> -- bash (pod-name can be checked by kubectl get pods command, and you can choose any pod with the word broker in its name ), and there are corresponding commands in the /pulsar/bin path of the pod. For more information about pulsar-admin, please refer to the official documentation.

Before you start

1. Install KubeBlocks.
2. Create a Pulsar cluster.

Configure cluster parameters by configuration file

Using kubectl to configure pulsar cluster requires modifying the configuration file.

1. Modify the Pulsar broker.conf file, in this case, it is pulsar-broker-broker-config.

   kubectl edit cm pulsar-broker-broker-config -n demo

2. Check whether the configuration is done.

   kubectl get pod -l app.kubernetes.io/name=pulsar-broker

Configure cluster parameters with OpsRequest

1. Define an OpsRequest file and configure the parameters in the OpsRequest in a yaml file named mycluster-configuring-demo.yaml. In this example, lostBookieRecoveryDelay is configured as 1000.

   apiVersion: apps.kubeblocks.io/v1alpha1
   kind: OpsRequest
   metadata:
     name: mycluster-configuring-demo
     namespace: demo
   spec:
     clusterName: mycluster
     reconfigure:
       componentName: bookies
       configurations:
       - keys:
         - key: bookkeeper.conf
           parameters:
           - key: lostBookieRecoveryDelay
             value: "1000"
         name: bookies-config
     preConditionDeadlineSeconds: 0
     type: Reconfiguring
   EOF

   Field	Definition
   metadata.name	It specifies the name of this OpsRequest.
   metadata.namespace	It specifies the namespace where this cluster is created.
   spec.clusterName	It specifies the cluster name that this operation is targeted at.
   spec.reconfigure	It specifies a component and its configuration updates.
   spec.reconfigure.componentName	It specifies the component name of this cluster.
   spec.configurations	It contains a list of ConfigurationItem objects, specifying the component's configuration template name, upgrade policy, and parameter key-value pairs to be updated.
   spec.reconfigure.configurations.keys.key	It specifies the configuration map.
   spec.reconfigure.configurations.keys.parameters	It defines a list of key-value pairs for a single configuration file.
   spec.reconfigure.configurations.keys.parameter.key	It represents the name of the parameter you want to edit.
   spec.reconfigure.configurations.keys.parameter.value	It represents the parameter values that are to be updated. If set to nil, the parameter defined by the Key field will be removed from the configuration file.
   spec.reconfigure.configurations.name	It specifies the configuration template name.
   preConditionDeadlineSeconds	It specifies the maximum number of seconds this OpsRequest will wait for its start conditions to be met before aborting. If set to 0 (default), the start conditions must be met immediately for the OpsRequest to proceed.

2. Apply the configuration opsRequest.

   kubectl apply -f mycluster-configuring-demo.yaml

3. Verify the configuration.

   1. Check the progress of configuration:

      kubectl get ops

   2. Check whether the configuration is done.

      kubectl get pod -l app.kubernetes.io/name=pulsar

note

Just in case you cannot find the configuration file of your cluster, you can use kbcli to view the current configuration file of a cluster.

kbcli cluster describe-config mycluster -n demo

From the meta information, the cluster mycluster has a configuration file named broker.conf.

You can also view the details of this configuration file and parameters.

• View the details of the current configuration file.

  kbcli cluster describe-config mycluster --show-detail -n demo

• View the parameter description.

  kbcli cluster explain-config mycluster -n demo | head -n 20