On Wed 01/May/2013 03:04:52 +0200 Mark Andrews wrote:
> In message <[email protected]>, Alessandro Vesely writes:
>> On Tue 30/Apr/2013 01:07:42 +0200 Mark Andrews wrote:
>>> 
>>> SPF is techically superior to TXT is lots of ways.
>>> 
>>> [...]
>>> 
>>> For TXT you need to lookup the existing RRset, extract
>>> the v=spf1 record from it.  You then need to create a
>>> UPDATE message to delete just that record as well as add
>>> the new TXT record.   You then have to hope that no one
>>> else is performing a simultaneous update as you may get
>>> two TXT v=spf1 records in the RRset.
>> 
>> That's true, except that one has TXT records anyway.
> 
>       nsupdate
>       update del example.com SPF
>       update add example.com 3600 SPF v=spf1 ....
>       send
> 
> [intricacies of doing so in the face of multiple TXT records elided]

Thanks for the examples.

> I'm sure I could come up with a more compact way of identifying
> a spf record but it wouldn't be needed if people published type
> SPF.

You must mean "if people published SPF _only_".

What percentage of NS servers use dynamic updates primarily?  (I only
happened to use nsupdate occasionally, e.g. to fix dhcp hiccups.)

Switching to fully dynamic management would be a major evolutionary
step for DNS, and it will certainly make the arguments for strong DNS
typing more stringent.

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