[CentOS] Hint for nslookup wanted ...

Tue Oct 11 13:53:12 UTC 2016
Richard Mann <rmann at ilsworld.com>

> -----Original Message-----
> From: centos-bounces at centos.org [mailto:centos-bounces at centos.org] On
> Behalf Of Anand Buddhdev
> Sent: Tuesday, October 11, 2016 9:28 AM
> To: CentOS mailing list <centos at centos.org>
> Subject: Re: [CentOS] Hint for nslookup wanted ...
> 
> On 11/10/16 15:23, Richard Mann wrote:
> 
> > Did your google break?
> >
> > For just IPv6
> > nslookup -type=AAAA www.example.com
> >
> > For all records
> > nslookup -type=any www.example.com
> 
> This is bad advice, because in DNS, ANY != ALL

As I said: For all records.  Reading comprehension can be important.

> 
> If you query with qtype=any, and you ask a caching resolver, then it
> will return to you all the records that are in its cache at that time,
> which may or may not include the records you want.
> 
> In order to definitively get the A as well as the AAAA records, one
> needs to ask for them specifically:
> 
> nslookup -type=AAAA www.example.com
> nslookup -type=A www.example.com
> 
> This makes a cache explicitly look up those types of records if it
> doesn't already have them.
> 
> Regards,
> Anand
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> https://lists.centos.org/mailman/listinfo/centos