Resolving problems

[Nate Campi]

On Tue, Mar 12, 2002 at 05:36:43PM +0000, Simon Waters wrote:
> 
> Darren Coleman wrote:

> > Ultimately I need to figure out whether or not this is a configuration
> > problem at our end (which would seem odd given that this is the first
> > instance I've heard of where our servers can't resolve a legitimate Internet
> > facing domain) or whether this is a problem at "anchorvans.co.uk" end.
> > Either way, it doesn't explain why I can't get the MX (etc) info from the
> > domain, and ns.watson.ibm.com (for example) can...
> 
> I think they are giving you bad data. 
> 
> It sounds like your BIND 8 cache is getting corrupted by the bad
> data. That would be a BIND bug (and possibly an important one).

It doesn't look like corrupted cache, but BIND tossing the oversized
response entirely:

 $ dig  @map1.dns.gxn.net anchorvans.co.uk any
 
 ; <<>> DiG 8.3 <<>> @map1.dns.gxn.net anchorvans.co.uk any
 ; (1 server found)
 ;; res options: init recurs defnam dnsrch
 ;; got answer:
 ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6
 ;; flags: qr aa rd; QUERY: 1, ANSWER: 9, AUTHORITY: 4, ADDITIONAL: 4
 ;; QUERY SECTION:
 ;;      anchorvans.co.uk, type = ANY, class = IN
 
 ;; ANSWER SECTION:
 anchorvans.co.uk.       5M IN MX        10 mx1.anchorvans.co.uk.
 anchorvans.co.uk.       5M IN MX        10 mx2.anchorvans.co.uk.
 anchorvans.co.uk.       5M IN MX        10 mx3.anchorvans.co.uk.
 anchorvans.co.uk.       1D IN NS        map1.dns.gxn.net.
 anchorvans.co.uk.       1D IN NS        map2.dns.gxn.net.
 anchorvans.co.uk.       1D IN NS        map3.dns.gxn.net.
 anchorvans.co.uk.       1D IN NS        map4.dns.gxn.net.
 anchorvans.co.uk.       1D IN SOA       map1.dns.gxn.net.
 hostmaster.freenetname.co.uk. (
                                         1               ; serial
                                         46m40s          ; refresh
                                         2H              ; retry
                                         1W              ; expiry
                                         5M )            ; minimum
 
 anchorvans.co.uk.       5M IN MX        10 mx0.anchorvans.co.uk.
 
 ;; AUTHORITY SECTION:
 anchorvans.co.uk.       1D IN NS        map1.dns.gxn.net.
 anchorvans.co.uk.       1D IN NS        map2.dns.gxn.net.
 anchorvans.co.uk.       1D IN NS        map3.dns.gxn.net.
 anchorvans.co.uk.       1D IN NS        map4.dns.gxn.net.
 
 ;; ADDITIONAL SECTION:
 mx0.anchorvans.co.uk.   5M IN A         195.147.246.49
 mx1.anchorvans.co.uk.   5M IN A         195.147.246.220
 mx2.anchorvans.co.uk.   5M IN A         195.147.246.224
 mx3.anchorvans.co.uk.   5M IN A         195.147.246.36
 
 ;; Total query time: 459 msec
 ;; FROM: ns1.sjc to SERVER: map1.dns.gxn.net  195.224.255.22
 ;; WHEN: Tue Mar 12 10:04:32 2002
 ;; MSG SIZE  sent: 34  rcvd: 653
 
The size of the reply is 653 bytes. My BIND 8.3.1 servers can't resolve
"ANY" queries properly for this domain:

 $ dig anchorvans.co.uk any
 
 ; <<>> DiG 8.3 <<>> anchorvans.co.uk any
 ;; res options: init recurs defnam dnsrch
 ;; got answer:
 ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 4
 ;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 4, ADDITIONAL: 1
 ;; QUERY SECTION:
 ;;      anchorvans.co.uk, type = ANY, class = IN
 
 ;; ANSWER SECTION:
 anchorvans.co.uk.       4H IN NS        map1.dns.gxn.net.
 anchorvans.co.uk.       4H IN NS        map2.dns.gxn.net.
 anchorvans.co.uk.       4H IN NS        map3.dns.gxn.net.
 anchorvans.co.uk.       4H IN NS        map4.dns.gxn.net.
 
 ;; AUTHORITY SECTION:
 anchorvans.co.uk.       4H IN NS        map1.dns.gxn.net.
 anchorvans.co.uk.       4H IN NS        map2.dns.gxn.net.
 anchorvans.co.uk.       4H IN NS        map3.dns.gxn.net.
 anchorvans.co.uk.       4H IN NS        map4.dns.gxn.net.
 
 ;; ADDITIONAL SECTION:
 map1.dns.gxn.net.       23h58m44s IN A  195.224.255.22
 
 ;; Total query time: 155 msec
 ;; FROM: ns1.sjc to SERVER: default -- 127.0.0.1
 ;; WHEN: Tue Mar 12 10:05:47 2002
 ;; MSG SIZE  sent: 34  rcvd: 209
 
It would appear that an MTA doing ANY queries to get the MX info for
anchorvans.co.uk would be out of luck. Since this is standard for MTAs,
I'd say anchorvans.co.uk is missing out on a lot of mail.
-- 
Nate

A complex system that works is invariably found to have evolved from
a simple system that worked.  -John Gall