# Server Hardening

Server hardening involves implementing various security measures to protect your server from unauthorized access, attacks, and vulnerabilities. By following these steps, you can enhance the security posture of your Rdiffweb server.

## Configure a Reverse Proxy

Setting up a reverse proxy can provide an additional layer of security and improve the performance and scalability of your web applications.

Read more:

```{toctree}
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networking
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## Encrypt Network Traffic (SSL)

Configure you server to make use of secure protocols like SSL/TLS to encrypt network traffic.
Obtain and install valid SSL certificates from trusted certificate authorities.

[How to configure letencrypt](https://wiki.debian.org/LetsEncrypt)

## Configure Firewall

Set up a firewall to control incoming and outgoing network traffic. Only allow necessary ports and protocols.
You should consider to expose only ports 80 (http), 433 (https) and 22 (ssh).
Make sure you are not exposing default port 8080 used by default by Rdiffweb for unsecure communication.
Close all unused ports and services to minimize potential attack vectors.
Implement a default deny policy, only permitting essential services.

## Secure remote SSH access

The SSH (Secure Shell) server is a critical component of remote server access. Implementing proper security measures for SSH helps protect against unauthorized access and potential attacks.

1. Disable SSH protocol versions 1 and use only SSH protocol version 2, which offers stronger security.
2. Change the default SSH port (typically 22) to a non-standard port to reduce visibility to potential attackers. Choose a port outside the well-known port range.
3. Configure SSH to only allow specific users or groups to connect, limiting access to authorized individuals.
4. Implement key-based authentication instead of relying solely on passwords. Generate SSH key pairs for each user and disable password-based authentication.
5. Enforce strong password policies for SSH users, including the use of complex, unique passwords.
6. Restrict SSH access to specific IP addresses or IP ranges using firewall rules or TCP wrappers. This helps limit access to trusted networks or specific machines.
7. Implement SSH brute-force attack protection mechanisms, such as [fail2ban](fail2ban.md), to automatically block IP addresses that exhibit suspicious behavior.

Read more:

```{toctree}
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fail2ban
```

## Update and Patch Management

Regularly update and patch your server's operating system, software, and applications to ensure you have the latest security fixes and bug patches.
Enable automatic updates or establish a systematic update process.
Rdiffweb is continiously updated with secutiry enhancements.

