# Zookeeper

{% hint style="info" %}
Only one Zookeeper connection is allowed.

The name must be zookeeper.

See [JSON schema](https://docs.lenses.io/latest/deployment/configuration/overview#json-schema-support) for support.

Environment variables are supported; escape the dollar sign

```yaml
sslKeystorePassword:
  value: "\${ENV_VAR_NAME}"
```

{% endhint %}

{% hint style="success" %}
Only one Zookeeper connection is allowed.
{% endhint %}

## Simple configuration, without metrics <a href="#simple-configuration-without-metrics" id="simple-configuration-without-metrics"></a>

```yaml
zookeeper:
- name: Zookeeper
  version: 1
  tags: ["tag1"]
  configuration:
    zookeeperUrls:
      value:
        - my-zookeeper-host-0:2181
        - my-zookeeper-host-1:3181
        - my-zookeeper-host-2:4181
    # optional, a suffix to Zookeeper's connection string
    zookeeperChrootPath: 
      value: "/mypath" 
    zookeeperSessionTimeout: 
      value: 10000 # in milliseconds
    zookeeperConnectionTimeout: 
      value: 10000 # in milliseconds
```

## Simple configuration, with JMX metrics <a href="#simple-configuration-with-jmx-metrics" id="simple-configuration-with-jmx-metrics"></a>

Simple configuration with Zookeeper metrics read via JMX.

```yaml
zookeeper:    
- name: Zookeeper
  version: 1
  tags: ["tag1"]
  configuration:
    zookeeperUrls:
      value:
        - my-zookeeper-host-0:2181
        - my-zookeeper-host-1:3181
        - my-zookeeper-host-2:4181
    # optional, a suffix to Zookeeper's connection string
    zookeeperChrootPath: 
      value: "/mypath" 
    zookeeperSessionTimeout: 
      value: 10000 # in milliseconds
    zookeeperConnectionTimeout: 
      value: 10000 # in milliseconds
    # all metrics properties are optional
    metricsPort: 
      value: 9581
    metricsType: 
      value: JMX
    metricsSsl: 
      value: false
```

With such a configuration, Lenses will use 3 Zookeeper nodes and will try to read their metrics from following URLs (notice the same port - 9581 - used for all of them, as defined by **metricsPort** property):

* my-zookeeper-host-0:9581
* my-zookeeper-host-1:9581
* my-zookeeper-host-2:9581