Proxy Hosts#
Proxy hosts are the core resource in PosternProxy. Each one tells Caddy to accept traffic for one or more domain names and forward it to an upstream service.
What a proxy host does#
When you create a proxy host, PosternProxy:
- Adds a Caddy route that matches the specified domain names
- Optionally enforces HTTPS and HSTS
- Forwards matching requests to the configured upstream (or load-balances across multiple upstreams)
- Optionally applies an access list, rate limit, custom headers, or custom error pages
- Manages TLS automatically via Let’s Encrypt (unless you supply a custom certificate)
The form tabs#
The Add / Edit Proxy Host modal has the following tabs:
| Tab | Purpose |
|---|---|
| Details | Domain names, primary upstream, basic options |
| Upstreams | Extra backends for load balancing |
| SSL | Certificate selection, HTTPS enforcement, HSTS |
| Locations | Sub-path routing overrides |
| Health | Active and passive health check settings |
| Security | Access list, rate limiting |
| Errors | Custom HTML for 404/502/503 responses |
| Headers | Request and response header injection |
| Advanced | Raw Caddy JSON merged into the route |
Quick reference#
| Setting | Description |
|---|---|
| Domain Names | One or more hostnames (press Enter after each) |
| Forward Scheme | http or https — protocol used to reach your upstream |
| Forward Hostname / IP | Internal address of the service to proxy |
| Port | Upstream port number |
| Force HTTPS | Redirect HTTP to HTTPS (otherwise the host is served over HTTP) |
| Access List | Restrict access by IP via an access list |
Enable / disable#
Each proxy host can be toggled on or off without deleting it. When disabled, Caddy removes the route immediately; traffic returns a 404 until re-enabled.