# TCP Appender

The TCP appender sends log events to a master server over TCP sockets. It can be used as a simple way to centralise logging when you have multiple servers or processes. It uses the node.js core networking modules, and so does not require any extra dependencies. Remember to call `log4js.shutdown` when your application terminates, so that the sockets get closed cleanly. It's designed to work with the [tcp-server](tcp-server.md), but it doesn't necessarily have to, just make sure whatever is listening at the other end is expecting JSON objects as strings.

## Configuration

- `type` - `tcp`
- `port` - `integer` (optional, defaults to `5000`) - the port to send to
- `host` - `string` (optional, defaults to `localhost`) - the host/IP address to send to
- `endMsg` - `string` (optional, defaults to `__LOG4JS__`) - the delimiter that marks the end of a log message
- `layout` - `object` (optional, defaults to a serialized log event) - see [layouts](layouts.md)

## Example

```javascript
log4js.configure({
  appenders: {
    network: { type: "tcp", host: "log.server" },
  },
  categories: {
    default: { appenders: ["network"], level: "error" },
  },
});
```

This will send all error messages to `log.server:5000`.