[PATCH] bind-sdb and notify

[Pramberger Peter]

Hi all!
I'm currently using sdb-ldap-1.1.0 with bind 9.3.1 to manage my master zones via
ldap. However all secondary dns servers are not within my control and use the
default rbtdb for the zones.

This is also the source of my problem. Bind doesn't send notifies to the slave
servers on reload or reconfigure. The only ways to ensure up-to-date zone data
on all servers are restarting bind, or waiting for the secondary servers
expiring the zones and checking for an update.

None of these seems to be acceptable to me, so I started "playing around" in the
bind sources. The result is attached to this post. Maybe someone can give some
comments on it.

I've modified zone_load to compare the actual serial number of persistent master
zones to the currently known serial. If the actual serial is greater, then a
zone notify will be scheduled. The actual notify may still be blocked if
notifies are disabled for this zone. zone_load itself will be triggered on every
reload, reconfig or zone maintenance.

Additionally it may be nice when bind checks automatically, whether the zone has
been updated. This check may occur on every request to the sdb zone, but I've no
idea how to do this. This may also have a major performance impact. Any comments
on this?


Regards,
Peter