Re: turning off EDNS0

Mark:

The upgrade and the -4 option seemed to fix the problem. I didn't
change the edns-udp-size since the firewall test passed.

I also specified "--enable-threads" in my build of 9.3.0, but I don't
know how 9.2.2-P1 was built. I see 5 named processes in 'ps' when I run
9.2.2-P1. Does that mean it was built with --enable-threads?

Thanks for your help.

Mark Andrews wrote:

>>I am running bind version "BIND 9.2.2-P1" and I notice that my query
>>times are very long. When I run Ethereal to see why, I see that initial
>>queries are sending the OPT pseudo RR. Almost every nameserver out
>>there responds to this with RCODE "format error" and then bind issues
>>another query without this extension.
>>
>>
>
> Actually the majority of servers out there know about EDNS.
>
>
>
>>This is really increasing my relsoving time. I would really like to
>>disable this, but apparently I can only do this on a per server basis.
>>
>>
>
> The delays caused by EDNS probes are generally not noticable to
> the end user.
>
> You are most probably seeing the side effects of the addition of
> AAAA records for A.GTLD-SERVERS.NET and B.GTLD-SERVERS.NET. This
> tickled a bug in BIND 9 (fixed in 9.2.5/9.3.1 out soon). This also
> exposed misconfigured firewalls that incorrectly dropped EDNS
> replies bigger than 512 octets. The EDNS referral to the COM /
> NET servers now exceeds 512 octets.
>
> Upgrade to 9.3.0 and run "named -4" to work around the BIND 9
> bug.
>
> Upgrade to 9.3.0 and set "edns-udp-size 512;" in options if you
> have a broken firewall. This should be seen as a short term
> work-around until you get the firewall fixed.
>
> You can determine if the firewall is misconfigured if you get
> a response to the first query and not to the second query.
>
> dig soa com +norec @a.root-servers.net
> dig soa com +norec +bufsize=1024 @a.root-servers.net
>
>
>
>>First, I would like to know how to disable this globally (hopefully
>>without recompililng). But something makes me think this is not what I
>>want to do. I just can't believe that ISC would release BIND9
>>configured by default to double resolving times. Am I doing something
>>wrong?
>>
>>---
>>Joe Harvell
>>
>>
>>
>>
>--
>Mark Andrews, ISC
>1 Seymour St., Dundas Valley, NSW 2117, Australia
>PHONE: +61 2 9871 4742 INTERNET: Mark_Andrews@isc.org
>
>
>