# Sidecar

{% hint style="info" %}
[**LeonaAgent V1.0**](https://github.com/LeonaLog) is coming, only for LeonaLog collectting log data.
{% endhint %}

Leona Sidecar is a lightweight configuration management system for different log collections, also called **`Backends`**. The leona node(s) acts as a centralized hub containing the configurations of log collections. On supported message-producing devices/hosts, sidecar can run as a serivce or daemon.

## Installation

You can get `.deb` or `.rpm` packages for LeonaLog Sidecar in our package repository.

### CentOS

Install the sidecar repository configuration and sidecar itself with the following commands:

```bash
rpm -Uvh https://packages.graylog2.org/repo/packages/graylog-sidecar-repository-1-2.noarch.rpm
yum install graylog-sidecar
```

Edit the configuration (see [Sidecar Configuration](#sidecar-configuration)) and active the sidecar as a system service:

```bash
vi /etc/graylog/sidecar/sidecar.yml

graylog-sidecar -service install

systemctl enable graylog-sidecar
systemctl start graylog-sidecar

```

### Ubuntu

Install the sidecar repository configuration and sidecar itself with the following commands:

```bash
wget https://packages.graylog2.org/repo/packages/graylog-sidecar-repository_1-2_all.deb
dpkg -i graylog-sidecar-repository_1-2_all.deb
apt-get update && apt-get install graylog-sidecar 
```

Edit the configuration (see [Sidecar Configuration ](#sidecar-configuration)) and activate the Sidecar as a system service:

```
vi /etc/graylog/sidecar/sidecar.yml

graylog-sidecar -service install

# Ubuntu 14.04 with Upstart
start graylog-sidecar

# Ubuntu 16.04 and later with systemd
systemctl enable graylog-sidecar
systemctl start graylog-sidecar
```

## Sidecar Configuration

Configuration example:

```yaml
# The URL to the Graylog server API.
server_url: "http://127.0.0.1:9006/api/"

# The API token to use to authenticate against the Graylog server API.
# This field is mandatory
server_api_token: "1i4dcd68svirjkl67adarifiu5k2i2essueprcciceqdvc87ocof"

# The node name of the sidecar. If this is empty, the sidecar will use the
# hostname of the host it is running on.
node_name: "c-192.168.120.15"

# The update interval in seconds. This configures how often the sidecar will
# contact the Graylog server for keep-alive and configuration update requests.
update_interval: 10

# This configures if the sidecar should skip the verification of TLS connections.
# Default: false
#tls_skip_verify: false

# This enables/disables the transmission of detailed sidecar information like
# collector statues, metrics and log file lists. It can be disabled to reduce
# load on the Graylog server if needed. (disables some features in the server UI)
send_status: true

...
```

Parameter descriptions:

* **`server_url`**: URL to the leona API, e.g. `http://192.168.120.100:9000/api/`
* **`server_api_token`**: The API token to use to authenticate against the leona server API. Note: <mark style="color:red;">**The token is mandatory and needs to be configured**</mark>.
* **`node_id`**: The node ID of the sidecar. This can be a path to a file or an ID string. Node: <mark style="color:red;">**Every sidecar instance needs a unique ID**</mark>.
* **`node_name`**: Name of the sidecar instance.
* **`update_interval`**: The interval where the sidecar will fetch new configurations from the leona server in seconds. The default is 10.
* **`tls_skip_verify`**: This configures if the sidecar should skip the verification of TLS connections. The default is false.
* **`send_status`**: This controls the transmission of detailed sidecar information like collector status, metrics and log file lists. **It can be disabled to reduce load on the leona server if needed**. The default is true.
* **`list_log_files`**: Send a directory listing to leona and display it on the host status page, e.g. `/var/log`. This can also be a list of directories. The default is `[]`.
* **`cache_path`**: The directory where the sidecar stores internal data.&#x20;
* **`collector_configuration_directory`**: The directory where the sidecar generates configurations for collectors.
* **`log_path`**: The directory where the sidecar stores its logs. The default is `/var/log/graylog-sidecar`.
* **`log_rotate_max_file_size`**: The maximum size of the log file before it gets rotated. The default is 10MiB.
* **`log_rotate_keep_files`**: The maximum number of old log files to retain.
* **`collector_binaries_accesslist`**: A list of binaries that are allowed to be executed by the sidecar. An empty list disables the access list feature.