IPv4 in IPv6 in AAAA records

Phil Howard phil-nsd-users at ipal.net
Mon Aug 23 23:20:03 UTC 2004

On Mon, Aug 23, 2004 at 09:27:53AM +0200, Miek Gieben wrote:

| [On 23 Aug, @08:31, Phil wrote in "IPv4 in IPv6 in AAAA records ..."]
| > I'm not sure where this syntax originates (maybe an RFC, I haven't looked).
| > But BIND and earlier NSD accepted an IPv6 format where the low order 32 bits
| > could be written in dotted decimal, at least if the high order 96 bits had
| > the value (in IPv6 form) ::FFFF.  So I could write an AAAA record like:
| > 
| > ham.org.        12H IN  AAAA    ::FFFF:
| > 
| > which would actually be the same as:
| > 
| > ham.org.        12H IN  AAAA    ::FFFF:D166:C049
| > 
| > It's just a slight convenience to have this.  I was just wondering if this
| I think it's in the RFC to allow this, so it should be added to zonec.
| But just to satisfy my own curiosity. Why do you need this?

I generate my zone files by means of scripts sourced from other kinds of
data I set up in slightly more abstract ways.  For example that data might
specify that a given web domain is hosted on a given server name and has
mail.  It will generate A records instead of CNAME records by getting the
IP address of the server the domain is hosted on.  It generates both the
name without "www." and with.  It generates the MX record appropriately as
well.  I also have an "v4inv6" option which generates AAAA records from the
IPv4 IP addresses like "::FFFF:${ipv4addr}".

I have since made a tool I can use my scripts to generate the normal IPv6
hexadecimal format for those, so I no longer need that support in zonec.
But for consistency, others may want it as more IPv6 is deployed.  I just
don't know all that parser stuff so I had no hope of implementing such a
fix myself.

| > is supposed to be in there or not.  When I upgraded to 2.1.2 from a pre-2
| > version, those records like the first one above became syntax errors, while
| > those like the second one worked OK.
| this is an extra reason to fix this,

I suppose.  Like I say, I now have a shell tool (a program in C) that does
the conversion, so I have no urgent need.  But others might; I just seem
to be the first to raise it.

| Phil Howard KA9WGN       | http://linuxhomepage.com/      http://ham.org/ |
| (first name) at ipal.net | http://phil.ipal.org/   http://ka9wgn.ham.org/ |

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