On 03-Apr-2002 at 02:33:32 Greg A. Woods wrote:
> Nope -- PTR records are supposed to always be returned in the same order
> they're listed in the zone file, and in most DNS resolver APIs the first
> one is known as the "official" hostname. Ideally that'll be the name
> the host knows of itself as (i.e. w.r.t. SMTP the one it puts in the 220
> banner it gives to connecting SMTP clients and the one it uses as the
> HELO/EHLO parameter when it connects to SMTP servers).
>
I don't think so:
{john}1: dig -x 141.163.66.134
; <<>> DiG 9.2.1rc1 <<>> -x 141.163.66.134
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 35687
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 4, ADDITIONAL: 4
;; QUESTION SECTION:
;134.66.163.141.in-addr.arpa. IN PTR
;; ANSWER SECTION:
134.66.163.141.in-addr.arpa. 21250 IN PTR mary.csd.plymouth.ac.uk.
134.66.163.141.in-addr.arpa. 21250 IN PTR mail.plymouth.ac.uk.
;; AUTHORITY SECTION:
163.141.in-addr.arpa. 45593 IN NS dns1.plymouth.ac.uk.
163.141.in-addr.arpa. 45593 IN NS dns2.cs.strath.ac.uk.
163.141.in-addr.arpa. 45593 IN NS dns0.plymouth.ac.uk.
163.141.in-addr.arpa. 45593 IN NS dns1.cs.strath.ac.uk.
;; ADDITIONAL SECTION:
dns0.plymouth.ac.uk. 85894 IN A 141.163.1.250
dns1.cs.strath.ac.uk. 8148 IN A 130.159.196.126
dns1.plymouth.ac.uk. 85894 IN A 141.163.165.131
dns2.cs.strath.ac.uk. 8146 IN A 130.159.196.125
;; Query time: 98 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Wed Apr 3 09:05:36 2002
;; MSG SIZE rcvd: 251
{john}2: dig -x 141.163.66.134
; <<>> DiG 9.2.1rc1 <<>> -x 141.163.66.134
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 44348
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 4, ADDITIONAL: 4
;; QUESTION SECTION:
;134.66.163.141.in-addr.arpa. IN PTR
;; ANSWER SECTION:
134.66.163.141.in-addr.arpa. 21249 IN PTR mail.plymouth.ac.uk.
134.66.163.141.in-addr.arpa. 21249 IN PTR mary.csd.plymouth.ac.uk.
;; AUTHORITY SECTION:
163.141.in-addr.arpa. 45592 IN NS dns2.cs.strath.ac.uk.
163.141.in-addr.arpa. 45592 IN NS dns0.plymouth.ac.uk.
163.141.in-addr.arpa. 45592 IN NS dns1.cs.strath.ac.uk.
163.141.in-addr.arpa. 45592 IN NS dns1.plymouth.ac.uk.
;; ADDITIONAL SECTION:
dns0.plymouth.ac.uk. 85893 IN A 141.163.1.250
dns1.cs.strath.ac.uk. 8147 IN A 130.159.196.126
dns1.plymouth.ac.uk. 85893 IN A 141.163.165.131
dns2.cs.strath.ac.uk. 8145 IN A 130.159.196.125
;; Query time: 70 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Wed Apr 3 09:05:38 2002
;; MSG SIZE rcvd: 251
The first gives 'mary', the second 'mail'.
Regards,
John.
------------------------------------------------------------------------
John Horne, University of Plymouth, UK Tel: +44 (0)1752 233914
E-mail: jhorne@???
PGP key available from public key servers