# TCP & TLS

The **tcp** output plugin allows to send records to a remote TCP server. The payload can be formatted in different ways as required.

## Configuration Parameters

| Key                | Description                                                                                                               | default   |
| ------------------ | ------------------------------------------------------------------------------------------------------------------------- | --------- |
| Host               | Target host where Fluent-Bit or Fluentd are listening for Forward messages.                                               | 127.0.0.1 |
| Port               | TCP Port of the target service.                                                                                           | 5170      |
| Format             | Specify the data format to be printed. Supported formats are *msgpack* *json*, *json\_lines* and *json\_stream*.          | msgpack   |
| json\_date\_key    | Specify the name of the time key in the output record. To disable the time key just set the value to `false`.             | date      |
| json\_date\_format | Specify the format of the date. Supported formats are *double*, *epoch* and *iso8601* (eg: *2018-05-30T09:39:52.000681Z*) | double    |

## TLS Configuration Parameters

The following parameters are available to configure a secure channel connection through TLS:

| Key             | Description                                                                                                                               | Default |
| --------------- | ----------------------------------------------------------------------------------------------------------------------------------------- | ------- |
| tls             | Enable or disable TLS support                                                                                                             | Off     |
| tls.verify      | Force certificate validation                                                                                                              | On      |
| tls.debug       | Set TLS debug verbosity level. It accept the following values: 0 (No debug), 1 (Error), 2 (State change), 3 (Informational) and 4 Verbose | 1       |
| tls.ca\_file    | Absolute path to CA certificate file                                                                                                      |         |
| tls.crt\_file   | Absolute path to Certificate file.                                                                                                        |         |
| tls.key\_file   | Absolute path to private Key file.                                                                                                        |         |
| tls.key\_passwd | Optional password for tls.key\_file file.                                                                                                 |         |

### Command Line

```bash
$ bin/fluent-bit -i cpu -o tcp://127.0.0.1:5170 -p format=json_lines -v
```

We have specified to gather [CPU](https://github.com/fluent/fluent-bit-docs/tree/16f30161dc4c79d407cd9c586a0c6839d0969d97/pipeline/input/cpu.md) usage metrics and send them in JSON lines mode to a remote end-point using netcat service, e.g:

#### Start the TCP listener

Run the following in a separate terminal, netcat will start listening for messages on TCP port 5170

```
$ nc -l 5170
```

Start Fluent Bit

```bash
$ bin/fluent-bit -i cpu -o stdout -p format=msgpack -v
Fluent Bit v1.x.x
* Copyright (C) 2019-2020 The Fluent Bit Authors
* Copyright (C) 2015-2018 Treasure Data
* Fluent Bit is a CNCF sub-project under the umbrella of Fluentd
* https://fluentbit.io

[2016/10/07 21:52:01] [ info] [engine] started
[0] cpu.0: [1475898721, {"cpu_p"=>0.500000, "user_p"=>0.250000, "system_p"=>0.250000, "cpu0.p_cpu"=>0.000000, "cpu0.p_user"=>0.000000, "cpu0.p_system"=>0.000000, "cpu1.p_cpu"=>0.000000, "cpu1.p_user"=>0.000000, "cpu1.p_system"=>0.000000, "cpu2.p_cpu"=>0.000000, "cpu2.p_user"=>0.000000, "cpu2.p_system"=>0.000000, "cpu3.p_cpu"=>1.000000, "cpu3.p_user"=>0.000000, "cpu3.p_system"=>1.000000}]
[1] cpu.0: [1475898722, {"cpu_p"=>0.250000, "user_p"=>0.250000, "system_p"=>0.000000, "cpu0.p_cpu"=>0.000000, "cpu0.p_user"=>0.000000, "cpu0.p_system"=>0.000000, "cpu1.p_cpu"=>1.000000, "cpu1.p_user"=>1.000000, "cpu1.p_system"=>0.000000, "cpu2.p_cpu"=>0.000000, "cpu2.p_user"=>0.000000, "cpu2.p_system"=>0.000000, "cpu3.p_cpu"=>0.000000, "cpu3.p_user"=>0.000000, "cpu3.p_system"=>0.000000}]
[2] cpu.0: [1475898723, {"cpu_p"=>0.750000, "user_p"=>0.250000, "system_p"=>0.500000, "cpu0.p_cpu"=>2.000000, "cpu0.p_user"=>1.000000, "cpu0.p_system"=>1.000000, "cpu1.p_cpu"=>0.000000, "cpu1.p_user"=>0.000000, "cpu1.p_system"=>0.000000, "cpu2.p_cpu"=>1.000000, "cpu2.p_user"=>0.000000, "cpu2.p_system"=>1.000000, "cpu3.p_cpu"=>0.000000, "cpu3.p_user"=>0.000000, "cpu3.p_system"=>0.000000}]
[3] cpu.0: [1475898724, {"cpu_p"=>1.000000, "user_p"=>0.750000, "system_p"=>0.250000, "cpu0.p_cpu"=>1.000000, "cpu0.p_user"=>1.000000, "cpu0.p_system"=>0.000000, "cpu1.p_cpu"=>2.000000, "cpu1.p_user"=>1.000000, "cpu1.p_system"=>1.000000, "cpu2.p_cpu"=>1.000000, "cpu2.p_user"=>1.000000, "cpu2.p_system"=>0.000000, "cpu3.p_cpu"=>1.000000, "cpu3.p_user"=>1.000000, "cpu3.p_system"=>0.000000}]
```

No more, no less, it just works.


---

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