> ## Documentation Index
> Fetch the complete documentation index at: https://docs.streamnative.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Multi-Tenancy

## Topic Naming Rule

Pulsar supports [multi-tenancy](https://pulsar.apache.org/docs/next/concepts-multi-tenancy/). The client side should specifies a long topic name URL like `"persistent://tenant/ns/topic"`. StreamNative leverages Pulsar's multi-tenancy feature and keeps the compatibility with the short topic names in Kafka.

For Kafka client users, they should follow the topic naming rule in this section. Otherwise, unexpected behaviors might happen.

You should specific topic names like:

* `topic`: it refers the topic `persistent://public/default/topic` in the `public/default` namespace.
* `tenant.ns.topic`: it refers the topic `persistent://tenant/ns/topic` in the `tenant/ns` namespace.
* `tenant.ns.xxx.yyy`: it refers the topic `persistent://tenant/ns/xxx.yyy` in the `tenant/ns` namespace.

In short, use a short topic name if you don't use the multi-tenancy feature. Otherwise, add the namespace prefix for topics in non-default namespaces. Besides, Kafka clients can only access namespaces whose name doe not contain any dot character.

<Note title="Note">
  In early versions of StreamNative Cloud clusters, the topic naming style is similar to Pulsar, i.e. you need to specify `tenant/ns/topic` rather than `tenant.ns.topic` to access topic `topic` in namespace `tenant/ns`.
</Note>

## Listing topics

By default, when listing topics via Kafka clients or Kafka CLI, only topics in the default namespace will be listed. This behavior is intended to avoid accessing other namespaces that you might not have permission to access.

If you want to list topics in some other namespaces (e.g. `tenant1/ns1` and `tenant2/ns2`), you can use Pulsar admin CLI to [update the configuration dynamically](https://pulsar.apache.org/docs/next/admin-api-brokers/#update-broker-conf-dynamically):

```bash theme={null}
./bin/pulsar-admin brokers update-dynamic-config --config kopAllowedNamespaces --value "tenant1/ns1,tenant2/ns2"
```

For the permission to list topics, you need to grant produce or consume permissions on all namespaces in the `kopAllowedNamespaces` config to the role you have. See [Kafka ACLs on StreamNative Cloud](/cloud/security/access/access-control-lists/kafka-acls) for more details.

Take the command above for example and assume the role is `user`, you need to run the following commands to grant the permissions:

```bash theme={null}
./bin/pulsar-admin namespaces grant-permission --actions produce --role user tenant1/ns1
./bin/pulsar-admin namespaces grant-permission --actions produce --role user tenant2/ns2
```

You can also grant the permissions simply in the cloud console UI.

<Note title="Note">
  It's highly recommended to add the namespace to the `kopAllowedNamespaces` config when you created a topic used by Kafka clients in a new namespace. For now, you need to execute the `pulsar-admin brokers` command manually to update this config. In future, this step will be done automatically in the cloud console.
</Note>