infra-scripts/proxy/README.md

Proxy Server

Deploys a secure reverse proxy with Tailscale + Nginx Proxy Manager.

Quick Start

curl -fsSL https://gitea.arnodo.fr/Damien/infra-scripts/raw/branch/main/proxy/install.sh | bash

Components

• Tailscale: Private network access (SSH, admin panel)
• Nginx Proxy Manager: Public reverse proxy (HTTP/HTTPS)
• UFW: Firewall (only 80/443 exposed publicly)
• fail2ban + unattended-upgrades: Basic hardening

Environment Variables

Variable	Default	Description
PROXY_HOSTNAME	proxy	Server hostname
TZ	Europe/Paris	Timezone

Example:

PROXY_HOSTNAME=myproxy TZ=America/New_York curl -fsSL https://gitea.arnodo.fr/Damien/infra-scripts/raw/branch/main/proxy/install.sh | bash

What it does

1. Sets hostname
2. Installs base packages (vim, fail2ban, unattended-upgrades, at)
3. Installs and connects Tailscale (will prompt for authentication)
4. Configures sysctl for exit-node capability
5. Installs Docker
6. Configures UFW (80/443 public, everything else via Tailscale only)
7. Deploys Nginx Proxy Manager
8. Exposes NPM admin panel via Tailscale serve
9. Temporarily opens SSH port 22 for 5 minutes (safety net)

SSH Safety Net

During installation, SSH port 22 is temporarily opened for 5 minutes to prevent lockout if you're connected via public IP. After 5 minutes, it will be automatically closed and only Tailscale SSH will work.

# List scheduled jobs
sudo atq

# Cancel the scheduled SSH closure (replace N with job number)
sudo atrm N

# Manually close SSH port 22 if needed
sudo ufw delete allow 22/tcp

Post-install

• Access NPM admin: https://proxy.<your-tailnet>.ts.net
• Default credentials: admin@example.com / changeme
• Optionally approve exit-node in Tailscale admin console

Centralized log reception (rsyslog)

A fail2ban jail running inside an exposed service's own LXC only ever sees this proxy's tailnet IP as the connection source, so it would end up banning the proxy itself instead of the actual client. Detection has to stay where the signal is (the service's application log); banning has to happen here, where public connections terminate. Services forward their logs to this proxy over TCP so a jail here can act on them.

File	Purpose
/etc/rsyslog.d/10-remote-receiver.conf	Generic imtcp listener, port RSYSLOG_PORT (default 5514). Anything not claimed by a more specific routing file lands in /var/log/remote/<sender-hostname>.log.
/etc/rsyslog.d/50-<service>.conf	One per exposed service. Routes by tag/programname into that service's own logfile for its dedicated fail2ban jail.
/etc/logrotate.d/remote-logs	Rotation for everything under /var/log/remote/ (copytruncate, so fail2ban never loses its file descriptor across a rotation).

Adding a new exposed service is a matter of dropping its 50-<service>.conf here — nothing else in this list needs to change. A minimal example that routes messages tagged myservice into their own file, in addition to the generic catch-all:

$RuleSet remoteLogs
if $programname == 'myservice' then {
    action(type="omfile" file="/var/log/myservice/myservice.log")
}
$RuleSet RSYSLOG_DefaultRuleset

RSYSLOG_PORT and RSYSLOG_BIND_ADDR (default 0.0.0.0) are overridable via environment. The default bind is safe as-is: UFW's default-deny only opens 80/tcp and 443/tcp publicly, so port 5514 is reachable exclusively over tailscale0 regardless of the bind address. Binding to the tailnet IP directly was considered and rejected — it would require tailscale up to have already succeeded before rsyslog is configured, which complicates the script's flow (a missing TS_AUTHKEY is tolerated today). The residual risk is log injection from anything that reaches the port (which can trigger a false fail2ban ban); narrow RSYSLOG_BIND_ADDR to a specific tailnet IP if that risk becomes a concern.