fix broken links

content/fundamentals/intro.md

@@ -8,4 +8,4 @@ Status: published
 Category: fundamentals
 slug: 001
 
-This series is a starting point for people looking to host their own on-line services from home. A good place to start is by reading the [homebrewserver.club principles]({filename}manifesto.md) to understand what the homebrew servers are about and how we make the choices we do. Then have a look at the [hardware guide]({filename}/hardware.md) or [setting up a server behind your home router.]({filename}portforwarding.md)
+This series is a starting point for people looking to host their own on-line services from home. A good place to start is by reading the [homebrewserver.club principles]({filename}manifesto.md) to understand what the homebrew servers are about and how we make the choices we do. Then have a look at the [hardware guide]({filename}hardware.md) or [setting up a server behind your home router.]({filename}port_forwarding.md)