<br><div class="gmail_quote">On Fri, Apr 8, 2011 at 1:49 AM, Mark Andrews <span dir="ltr"><<a href="mailto:marka@isc.org">marka@isc.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
Please explain the operating conditions under which when you think<br>
this is a sensible thing to do?<br>
<br>
A nameserver without address records is pointless.<br>
A nameserver pointing to a CNAME/DNAME causes resolution problems.<br>
</blockquote><div><br>
<br>
Here is an example that works in BIND 9.6x:<br>
$ORIGIN .<br>
$TTL 86400 ; 1 day<br>
<a href="http://mydomain.com.au">mydomain.com.au</a> IN SOA <a href="http://ns0.mydomain.com.au">ns0.mydomain.com.au</a>. <a href="http://admin.mydomain.com.au">admin.mydomain.com.au</a>. (<br>
2011010104 ; serial<br>
43200 ; refresh (12 hours)<br>
7200 ; retry (2 hours)<br>
1209600 ; expire (2 weeks)<br>
1800 ; minimum (30 minutes)<br>
)<br>
$TTL 1800 ; 30 minutes<br>
NS <a href="http://ns0.mydomain.com.au">ns0.mydomain.com.au</a>. <br>
NS <a href="http://ns1.mydomain.com.au">ns1.mydomain.com.au</a>. <br>
NS <a href="http://ns2.mydomain.com.au">ns2.mydomain.com.au</a>.<br>
A 1.1.1.1<br>
MX 10 <a href="http://mail.mydomain.com.au">mail.mydomain.com.au</a>.<br>
$ORIGIN <a href="http://mydomain.com.au">mydomain.com.au</a>.<br>
ftp A 1.1.1.1<br>
mail A 2.2.2.2<br>
pop CNAME mail<br>
smtp CNAME mail<br>
ssh A 1.1.1.1<br>
www CNAME <a href="http://mydomain.com.au">mydomain.com.au</a>.<br>
<br>
<br>
Is this domain 100% valid?... no... but it still works. The A records
for the name servers are actually still resolving since the regsitrar
will return them in glue. But understandably... this domain is not 100% valid.<br>
<br>
But to force the domain offline is just preventing many shared hosting
environments to move to newer versions of BIND (or switch off of BIND
since they do not understand the problem).<br>
Give a warning... that is fine... But to prevent the domain from loading
is just too harsh and an immediate drastic measure during an upgrade.
It would be nice if it was a configuration option just like all of the other checks.<br>
</div></div><br>This same function seems also to be called in "update.c"...... also causing problems. I would just like this function to never be called but I have not been able to determine if it does other things necessary.<br>
<br>-- <br>Best regards,<br>-Rodney Hives<br>(Internet user since... well.... before Gore built it....)<br><br>