more documentation

diff --git a/README.rst b/README.rst
index 95d586fe8b5bbd3642ff69dbc7efb673b7632a9c..be662df41ff9bd96d095240e1d3b129f193ebbe3 100644 (file)
--- a/README.rst
+++ b/README.rst
@@ -62,15 +62,17 @@ particular, **change the password**!
 Now, let's go on with the CGI scripts. They are using Python 2, so make sure you 
 have that installed. There are two scripts: One is used for clients to detect 
 their current external IP address, and one is used to do the actual update of 
 Now, let's go on with the CGI scripts. They are using Python 2, so make sure you 
 have that installed. There are two scripts: One is used for clients to detect 
 their current external IP address, and one is used to do the actual update of 

-the domain. The first script should be available on a domain that is available 
-only through a single protocol, i.e., IPv4 only or IPv6 only.  This is required 
-to reliably detect the current address of the given protocol. If you want to 
-support both IPv4 and IPv6, I suggest you have three domains 
+the domain. The first script is used by the "web" IP detection method (see 
+client configuration below). It should be available on a domain that is 
+available only through a single protocol, i.e., IPv4 only or IPv6 only. This is 
+required to reliably detect the current address of the given protocol. If you 
+want to support both IPv4 and IPv6, I suggest you have three domains 

 ``ipv4.ns.example.com``, ``ipv6.ns.example.com`` and ``ns.example.com`` where 
 only the latter is available via both protocols (this is something you have to 
 ``ipv4.ns.example.com``, ``ipv6.ns.example.com`` and ``ns.example.com`` where 
 only the latter is available via both protocols (this is something you have to 

-configure in your ``example.com`` zone). All can serve the same scripts (e.g. 
-via a ``ServerAlias`` in the apache configuration). I also **strongly suggest** 
-you make these domains *HTTPS-only*, as the client script will send a password!
+configure in your ``example.com`` DNS zone). All can serve the same scripts 
+(e.g. via a ``ServerAlias`` in the apache configuration). I also **strongly 
+suggest** you make these domains *HTTPS-only*, as the client script will send a 
+password!

 
 Choose some directory (e.g., ``/srv/ns.example.com``) for the new domain, and 
 copy the content of ``server-scripts`` there. Now configure your webserver 
 
 Choose some directory (e.g., ``/srv/ns.example.com``) for the new domain, and 
 copy the content of ``server-scripts`` there. Now configure your webserver 


@@ -92,13 +94,18 @@ Client setup (using the script)
 
 You can find the client script at ``client-scripts/dyn-ns-client``. It requires 
 Python 3. Copy that script to the machine that should be available under the 
 
 You can find the client script at ``client-scripts/dyn-ns-client``. It requires 
 Python 3. Copy that script to the machine that should be available under the 

-dynamic domain. Also copy the sample configuration file ``dyn-ns-client.conf.dist`` to 
-``$HOME/.config/dyn-nsupdate/dyn-ns-client.conf``. (You can choose another 
-name, but then you will have to tell the script about it.) That file contains 
-comments that should explain everything. Note that the script can update a list 
-of domain names, in case you need the machine to have several names. It is 
-preferable to use a CNAME instead, this will reduce the number of updates 
-performed in the zone.
+dynamic domain. Also copy the sample configuration file 
+``dyn-ns-client.conf.dist`` to ``$HOME/.config/dyn-nsupdate/dyn-ns-client.conf``.
+You can choose another name, but then you will have to tell the script about it. 
+An important aspect of configuration is how to detect the current addresses of 
+the machine the script is running on. For IPv4, this can only be "web", which 
+can deal with NAT. For IPv6, the script can alternatively attempt to detect the 
+correct local address to use. The sample file contains comments that should 
+explain everything.
+
+Note that the script can update a list of domain names, in case you need the 
+machine to have several names. It is preferable to use a CNAME instead, this 
+will reduce the number of updates performed in the zone.

 
 To run the script regularly, simply set up a cronjob. You can do so by running 
 ``crontab -e``, and add a line as follows::
 
 To run the script regularly, simply set up a cronjob. You can do so by running 
 ``crontab -e``, and add a line as follows::