Add install from source

Signed-off-by: DL6ER <dl6er@dl6er.de>

docs/ftldns/compile.md

@@ -0,0 +1,38 @@
+We pre-compile *FTL*DNS for you to save you the trouble of compiling anything yourself. However, sometimes you may want to make your own modifications. To test them, you have to compile *FTL*DNS from source. Luckily, you don't have to be a programmer to build *FTL*DNS from source and install it on your system; you only have to know the basics we provide in here. With just a few commands, you can build *FTL*DNS from source like a pro.
+
+#### Installing the Required Software
+First, we'll install the basic software you'll need to compile from source, like the GCC compiler and other utilities.
+Install them by running the following command in a terminal:
+```
+sudo apt install build-essential libgmp-dev m4
+```
+
+You'll also need to compile a recent version of `nettle` as *FTL*DNS uses `libnettle` for handling DNSSEC. Compile and install a recent version of `nettle` (we tested 3.4) like
+```
+wget https://ftp.gnu.org/gnu/nettle/nettle-3.4.tar.gz
+tar -xvzf nettle-3.4.tar.gz
+cd nettle-3.4
+./configure
+make
+sudo make install
+```
+
+#### Get the *FTL*DNS source
+Now, clone the *FTL*DNS repo (or your own fork) to get the source code of *FTL*DNS:
+```
+git clone https://github.com/pi-hole/FTL.git
+cd FTL
+```
+
+If you want to build another branch and not `master`, use checkout to get to this branch (e.g. `git checkout development`).
+
+*FTL*DNS can be compiled and installed like
+```
+make -j 4
+sudo make install
+```
+
+Finally, restart *FTL*DNS to use the new binary:
+```
+sudo service pihole-FTL restart
+```

mkdocs.yml

@@ -26,6 +26,7 @@ pages:
   - 'Updating': 'main/update.md'
 - 'FTLDNS':
   - 'Overview': "ftldns/index.md"
+  - 'Install from source': "ftldns/compile.md"
   - 'Blocking mode': "ftldns/blockingmode.md"
   - 'RegEx blocking': "ftldns/regex.md"
 #  - 'Privacy levels': "ftldns/privacy.md"