On Mon, 18 Feb 2002, martin f krafft wrote:
> also sprach Jeff <jcoppock1@attbi.com> [2002.02.18.0103 +0100]:
> > > I have brackets around this in my main.cf. I do not know if this
> > > is your problem, but this line is all I needed to do:
> > >
> > > relayhost = [my.isp.mail.server.com]
> >
> > Brackets are not necessary, so that's not the problem. Are you sure
> > your hostname and origin settings are correct? Are on a network
> > that the server will listen too (your IP address)?
>
> brackets will make it use the A record or IP address straight, rather
> than asking postfix to figure out the MX record first.
>
> do
>
> host my.isp.mail.server.com
>
> and obtain the IP from the result. then, do these two:
>
> ping <ipaddress>
> telnet <ipaddress> 25
>
> report what you see. also, what's the entries in /var/log/mail.log,
> and the output of the `mailq` command?
>
Hi,
Thanks to all who replied. I've discovered (thanks to Martin's
suggestions) that the reason why my mail server is talking to
texlog.texas.rr.com instead of the smtp server that I specified
(smtp-server.austin.rr.com) is because the DNS server for my host (run by
the ISP) states that texlog.... is the mail server for my host. Witness
the following translated tcpdump output (see attached script to see how I
got this output) that I get when I send a mail :
08:17:39.870965 24.28.XX.XX.33467 > 24.93.35.62.53: 10894+ MX?
smtp-server.austin.rr.com. (43) (DF)
EG1@@mG]#>53.V*smtp-serveraustinrrcom
08:17:39.982657 24.93.35.62.53 > 24.28.XX.XX.33467: 10894* 1/4/5 MX
texlog.texas.rr.com. 10 (224) (DF)
E@=%]#>G5f*smtp-serveraustinrrcom<
texlogtexas^_ns2ns1@ns1ns2@9H]#f]# x]#>]#!T]#?
08:17:39.983107 24.28.XX.XX.33467 > 24.93.35.62.53: 10895+ A?
texlog.texas.rr.com. (37) (DF)
EA1@@mG]#>5-/*texlogtexasrrcom
08:17:40.056209 24.93.35.62.53 > 24.28.XX.XX.33467: 10895 1/4/4 A
24.93.35.223 (196) (DF)
E@=A]#>G5~*texlogtexasrrcomH]#9^Mns1austin9ns29ns2E9ns1~]# A]#>Z]#!l]#?
08:17:40.056649 24.28.XX.XX.54994 > 24.93.35.223.25: S
1776713462:1776713462(0) win 5840 <mss 1460,sackOK,timestamp 469512701
0,no
p,wscale 0> (DF)
E<O@@PDG]#i~
1
08:17:40.153124 24.93.35.223.25 > 24.28.XX.XX.54994: S
2682070823:2682070823(0) ack 1776713463 win 24616 <nop,nop,timestamp
357429
443 469512701,nop,wscale 0,nop,nop,sackOK,mss 1460> (DF)
E@@=]#G''i~`(_
M1
08:17:40.153224 24.28.XX.XX.54994 > 24.93.35.223.25: . ack 1 win 5840
<nop,nop,timestamp 469512711 357429443> (DF)
E4O@@PKG]#i~'(
2M
....and as you can see, this is why postfix is talking to the
texlog server (24.93.35.223). However, when I use dig, here is what I get
:
trillian:~# dig -t MX my_isp_assigned_hostname.austin.rr.com
; <<>> DiG 9.2.0 <<>> -t MX my_isp_assigned_hostname.austin.rr.com
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 33340
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
;; QUESTION SECTION:
;my_isp_assigned_hostname.austin.rr.com. IN MX
;; AUTHORITY SECTION:
austin.rr.com. 3600 IN SOA ns1.austin.rr.com.
rradm.austin.rr.com. 2002021801 3600 600 86400 3600
;; Query time: 108 msec
;; SERVER: 24.93.35.62#53(24.93.35.62)
;; WHEN: Thu Feb 21 08:25:38 2002
;; MSG SIZE rcvd: 87
...which I dont understand since the above output doesnt show
texlog.texas.rr.com as the mail server for my host. So now I have two
mysteries : (1) Why is postfix ignoring my relayhost parameter and
querying DNS and (2) Why am I not getting similar answers to what postfix
gets when querying my ISP DNS server?
For reference, I enclose again all non-commented lines in
/etc/postfix/main.cf :
command_directory = /usr/sbin
daemon_directory = /usr/lib/postfix
mynetworks = 127.0.0.0/8
smtpd_banner = $myhostname ESMTP $mail_name (Debian/GNU)
debugger_command =
PATH=/usr/bin:/usr/X11R6/bin
xxgdb $daemon_directory/$process_name $process_id & sleep 5
program_directory = /usr/lib/postfix
myhostname = trillian.megadodo.umb
myorigin = /etc/mailname
mydestination = trillian.megadodo.umb, localhost.localdomain
relayhost = smtp-server.austin.rr.com
mailbox_command = procmail -a "$EXTENSION"
mailbox_size_limit = 0
canonical_maps = hash:/etc/postfix/sender.map
Changes to my config since I first reported this problem : (1) I
changed the map file to point to canonical_maps. It was originally
pointing to sender_canonical_maps. (2) I edited /etc/mailname to put the
FQDN of my hostname (trillian.megadodo.umb). Previously 'hostname' would
report 'trillian'. It now reports the FQDN.
Thanks,
Jor-el
Attachment:
sniffer.pl
Description: tcpdump output xlater scarfed from the 'net