---
title: ping
sidebarTitle: ping
---
# `fastmcp.server.middleware.ping`
Ping middleware for keeping client connections alive.
## Classes
### `PingMiddleware`
Middleware that sends periodic pings to keep client connections alive.
Starts a background ping task on first message from each session. The task
sends server-to-client pings at the configured interval until the session
ends.
**Methods:**
#### `on_message`
```python
on_message(self, context: MiddlewareContext, call_next: CallNext) -> Any
```
Start ping task on first message from a session.