> For the complete documentation index, see [llms.txt](https://yeasy.gitbook.io/openstack_code_neutron/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://yeasy.gitbook.io/openstack_code_neutron/understanding/rpc/neutron_server_rpc.md).

# neutron-server RPC

这个rpc服务端主要通过neutron.server中主函数中代码执行

```python
neutron_rpc = service.serve_rpc()
```

方法的实现代码如下

```python
def serve_rpc():
    plugin = manager.NeutronManager.get_plugin()

    # If 0 < rpc_workers then start_rpc_listeners would be called in a
    # subprocess and we cannot simply catch the NotImplementedError.  It is
    # simpler to check this up front by testing whether the plugin supports
    # multiple RPC workers.
    if not plugin.rpc_workers_supported():
        LOG.debug(_("Active plugin doesn't implement start_rpc_listeners"))
        if 0 < cfg.CONF.rpc_workers:
            msg = _("'rpc_workers = %d' ignored because start_rpc_listeners "
                    "is not implemented.")
            LOG.error(msg, cfg.CONF.rpc_workers)
        raise NotImplementedError

    try:
        rpc = RpcWorker(plugin)

        if cfg.CONF.rpc_workers < 1:
            rpc.start()
            return rpc
        else:
            launcher = common_service.ProcessLauncher(wait_interval=1.0)
            launcher.launch_service(rpc, workers=cfg.CONF.rpc_workers)
            return launcher
    except Exception:
        with excutils.save_and_reraise_exception():
            LOG.exception(_('Unrecoverable error: please check log '
                            'for details.'))
```

其中，RpcWorker(plugin)主要通过调用plugin的方法来创建rpc服务端。

```python
self._servers = self._plugin.start_rpc_listeners()
```

该方法在大多数plugin中并未被实现，目前ml2支持该方法。

在neutron.plugin.ml2.plugin.ML2Plugin类中，该方法创建了一个topic为topics.PLUGIN的消费rpc。

```python
def start_rpc_listeners(self):
        self.endpoints = [rpc.RpcCallbacks(self.notifier, self.type_manager),
                          agents_db.AgentExtRpcCallback()]
        self.topic = topics.PLUGIN
        self.conn = n_rpc.create_connection(new=True)
        self.conn.create_consumer(self.topic, self.endpoints,
                                  fanout=False)
        return self.conn.consume_in_threads()
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://yeasy.gitbook.io/openstack_code_neutron/understanding/rpc/neutron_server_rpc.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.
