# Shell Scripts

> **Tip:** Install Docker Engine on Debian/Ubuntu.

```bash
curl -fsSL https://git.vanusys.com/VanuSystems/shell-scripts/raw/branch/main/install-docker.sh | sudo bash
```

> **Tip:** Configure registry mirrors for Docker and restart the daemon.

```bash
curl -fsSL https://git.vanusys.com/VanuSystems/shell-scripts/raw/branch/main/set-docker-mirror.sh | sudo bash
```

> **Tip:** Install Caddy web server on Debian/Ubuntu/Raspbian.

```bash
curl -fsSL https://git.vanusys.com/VanuSystems/shell-scripts/raw/branch/main/install-caddy.sh | sudo bash
```

> **Tip:** Append 2-space indent settings to `~/.vimrc`.

```bash
curl -fsSL https://git.vanusys.com/VanuSystems/shell-scripts/raw/branch/main/set-vim-2space.sh | bash
```

> **Tip:** Set up fail2ban with a strict profile (3 failures -> 24h ban, repeat offenders -> 1 week).

```bash
curl -fsSL https://git.vanusys.com/VanuSystems/shell-scripts/raw/branch/main/setup-fail2ban.sh | sudo bash
```

Override the detected SSH port, the sshd filter mode (`normal` by default: `aggressive`
also counts pre-auth client disconnects as failures, which bans legitimate users) or
whitelist an extra address:

```bash
curl -fsSL https://git.vanusys.com/VanuSystems/shell-scripts/raw/branch/main/setup-fail2ban.sh | sudo SSH_PORT=22,2222 IGNORE_IP=198.51.100.0/24 bash
```

> **Note:** the script whitelists the address of the current session when it can detect it
> (`SSH_CONNECTION`, `SSH_CLIENT`, or the utmp entry of its terminal). Piped through
> `curl ... | sudo bash` there is no terminal, so it prints a warning and you should pass
> `IGNORE_IP=<your address>` yourself — otherwise 3 failed attempts ban you for 24h
> (and 3 bans for a week).

> **Note:** the script refuses to continue when fail2ban's `logtarget` is not a file
> (`SYSLOG`, `STDERR`, ...), because the `recidive` jail reads that file to count bans
> and could otherwise never fire. Set `logtarget = /var/log/fail2ban.log` in
> `/etc/fail2ban/fail2ban.local` and re-run.