The Pulsar proxy is an optional gateway that you can run over the brokers in a Pulsar cluster. We recommend running a Pulsar proxy in cases when direction connections between clients and Pulsar brokers are either infeasible, undesirable, or both, for example when running Pulsar in a cloud environment or on Kubernetes or an analogous platform.
In order to run the Pulsar proxy, you need to have both a local ZooKeeper and configuration store quorum set up for use by your Pulsar cluster. For instructions, see this document. Once you have ZooKeeper set up and have connection strings for both ZooKeeper quorums, you can use the proxy command of the pulsar CLI tool to start up the proxy (preferably on its own machine or in its own VM):
To start the proxy:
$ cd /path/to/pulsar/directory $ bin/pulsar proxy \ --zookeeper-servers zk-0,zk-1,zk-2 \ --configuration-store-servers zk-0,zk-1,zk-2
You can run as many instances of the Pulsar proxy in a cluster as you would like.
The Pulsar proxy runs by default in the foreground. To stop the proxy, simply stop the process in which it's running.
We recommend running the Pulsar proxy behind some kind of load-distributing frontend, such as an HAProxy load balancer.
Once your Pulsar proxy is up and running, preferably behind a load-distributing frontend, clients can connect to the proxy via whichever address is used by the frontend. If the address were the DNS address pulsar.cluster.default, for example, then the connection URL for clients would be pulsar://pulsar.cluster.default:6650.
The Pulsar proxy can be configured using the proxy.conf configuration file. The following parameters are available in that file:
| Name | Description | Default |
|---|---|---|
| zookeeperServers | The ZooKeeper quorum connection string (as a comma-separated list) | |
| configurationStoreServers | Configuration store connection string (as a comma-separated list) | |
| zookeeperSessionTimeoutMs | ZooKeeper session timeout (in milliseconds) | 30000 |
| servicePort | The port to use for server binary Protobuf requests | 6650 |
| servicePortTls | The port to use to server binary Protobuf TLS requests | 6651 |
| statusFilePath | Path for the file used to determine the rotation status for the proxy instance when responding to service discovery health checks | |
| authenticationEnabled | Whether authentication is enabled for the Pulsar proxy | false |
| authenticationProviders | Authentication provider name list (a comma-separated list of class names) | |
| authorizationEnabled | Whether authorization is enforced by the Pulsar proxy | false |
| authorizationProvider | Authorization provider as a fully qualified class name | org.apache.pulsar.broker.authorization.PulsarAuthorizationProvider |
| brokerClientAuthenticationPlugin | The authentication plugin used by the Pulsar proxy to authenticate with Pulsar brokers | |
| brokerClientAuthenticationParameters | The authentication parameters used by the Pulsar proxy to authenticate with Pulsar brokers | |
| brokerClientTrustCertsFilePath | The path to trusted certificates used by the Pulsar proxy to authenticate with Pulsar brokers | |
| superUserRoles | Role names that are treated as “super-users,” meaning that they will be able to perform all admin | |
| forwardAuthorizationCredentials | Whether client authorization credentials are forwarded to the broker for re-authorization. Authentication must be enabled via authenticationEnabled=true for this to take effect. | false |
| maxConcurrentInboundConnections | Max concurrent inbound connections. The proxy will reject requests beyond that. | 10000 |
| maxConcurrentLookupRequests | Max concurrent outbound connections. The proxy will error out requests beyond that. | 50000 |
| tlsEnabledInProxy | Whether TLS is enabled for the proxy | false |
| tlsEnabledWithBroker | Whether TLS is enabled when communicating with Pulsar brokers | false |
| tlsCertificateFilePath | Path for the TLS certificate file | |
| tlsKeyFilePath | Path for the TLS private key file | |
| tlsTrustCertsFilePath | Path for the trusted TLS certificate pem file | |
| tlsHostnameVerificationEnabled | Whether the hostname is validated when the proxy creates a TLS connection with brokers | false |
| tlsRequireTrustedClientCertOnConnect | Whether client certificates are required for TLS. Connections are rejected if the client certificate isn’t trusted. | false |