Best Practices for Authoritative Servers

[Niall O'Reilly]

[ My MUA insists on normalizing timestamps to my timezone. I'm sorry. ]
On 1 Feb 2008, at 02:02, Mark Andrews wrote:
> 	If you have a loop in the axfr transfer graph all the slaves
> 	in that loop will converge to serving the same zone content
> 	(good) but will also keep resetting the refresh (with refresh
> 	not retry which is bad) and expiry timers (extremely bad).
>

On 1 Feb 2008, at 02:41, Kevin Darcy wrote:

> It's a shame BIND doesn't have any way of differentiating between  
> "peer"
> masters and "upstream" masters, so that the resetting behavior can be
> controlled.

	It's not the only software not to have a DWIM mode, and with
	good reason.  Somewhere, there has to be a responsible person
	in charge.  Identifying which elements of a configuration
	correspond, in the mind of that person, to a particular
	purpose, is not something which software can reliably do.

	As Mark explains (see above), "peer" masters are an "extremely
	bad" idea.  They give the opportunity of robustly perpetuating
	incorrect state, while making it more difficult to notice
	that something is wrong, since nothing appears broken from
	outside the circle of peers.


	Best regards,

	Niall O'Reilly
	University College Dublin IT Services

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