[bind10-dev] Config migration

[JINMEI Tatuya / 神明達哉]

At Thu, 2 May 2013 08:54:56 +0200,
Michal 'vorner' Vaner <michal.vaner at nic.cz> wrote:

> > My concern of this approach is that it'll be backward incompatible
> > change. [...]
> 
> Compatibility is, of course, a concern. I think it is also time to start
> thinking about some kind of automatic migration scripts, or something. My idea
> would be to:
> 
> • Have a version in each spec file
> • Store the version in the config too
> • Allow the spec file to specify script name for migration version x → y.
> • If the version stored in the config is older than the one in the spec file,
>   look for the script to migrate, allowing multiple steps. If there's a „gap“
>   between conversion versions, assume the versions don't need explicit
>   conversion, that they are compatible themselves.
> 
> This would solve upgrades, because we could rename options, move them around,
> etc. But we still don't have downgrades. Maybe we could use the same mechanism
> and have scripts to go down in the versions too. Or at least ask for manual
> inspection, highlighting the scripts that did the upgrade.

These look like nice topics to include at the phase of solving
configuration issues.

BTW, regarding the original specific problem of "use_ixfr", the
tentative conclusion at yesterday's team call was to allow the
incompatible change this time with documentation.

---
JINMEI, Tatuya
Internet Systems Consortium, Inc.