Binary zone file and journal compatibility between Bind9 versions

[Evan Hunt]

On Thu, Jan 09, 2025 at 11:40:33AM +0000, Klaus Darilion via bind-users wrote:
> For testing I often up- and downgrade Bind versions, ie. Between 9.18,
> 9.20 and 9.21. I wonder how stable the binary zone file format and
> journal file format is, and if there are changes in the binary format, if
> Bind would detect that and behave properly.
> 
> I am concerned about zones that end up containing some garbage. I never
> had any issues, but I wonder if that could happen.

So far as I can recall, raw zone file format hasn't changed.

Journal file format did change once, but the change should be detected
and handled correctly when upgrading, and there's a tool for upgrading or
downgrading manually if needed (named-journalprint -u and -d, respectively).

There was also a "map" file format for a while, and it was much touchier,
but it's been removed now.

-- 
Evan Hunt -- each at isc.org
Internet Systems Consortium, Inc.