Dynamic DNS and BIND

[Cricket Liu]

> We are currently running BIND 8.2.2 as a master DNS server with static
> addresses being assigned  by a DHCP server to PCs based on MAC address.
> Due to some project requirements we are now facing the prospect of
> removing the depencies of DHCP address allocation on MAC address and
> allowing Dynamic DNS updates. Two questions have arisen.
> 
> 1. How do we allow dynamic updates to the DNS while also being able to
> edit the Zone file and then apply the changes. Obviously if a copy of
> the DNS zone is taken for editing, by the time the changes are to be
> applied it is possible that a number of dynamic changes may have taken
> place and they will be "blown away" if the edited zone is reloaded. We
> have thought of potentially scripting a way for the dynamic changes
> during an edit to be logged and then essentially performing a "merge"
> but this is getting messy.

Manual changes to the zone and dynamic updates are, to an extent,
incompatible.  If you change the zone while the name server has one
or more dynamic updates logged, but not yet incorporated into the
zone data file, your manual changes will be lost.  If you can, you
should only make manual changes when the name server isn't running.
If you need to make changes while the name server is running, use a
tool like nsupdate to make the changes using dynamic update.

> 2. Is it possible to assign only part of our address range as accepting
> to dynamic updates while other areas remain static. This would be
> preferable without resorting to multiple zone files or some other
> workaround.

Unfortunately, there's no way to do that with BIND.

cricket

Acme Byte & Wire
cricket at acmebw.com
www.acmebw.com

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