Why do I have "host name lookup failure"?
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From: Ohmster on 3 Feb 2010 22:18 This is killing me, I am trying so hard to make this work and I am somehow missing something. I have sendmail setup to use my ISP as a smart host, use port 587, and use auth. I think I have that all setup properly, I used the settings from my prior sendmail setup that always worked. This is a little different this time though. Before I had my modem setup to go directly to my Fedora box, then to a hub, then to my local LAN. My Vonage router broke so I have a new one they sent me, a Motorola VT-2542-VD, then to the Fedora 12 box. So now the router is supply DHCP and it sets the resolv.conf file on my linux box as such: [ohmster(a)ohmster ~]$ cat /etc/resolv.conf # Generated by NetworkManager nameserver 192.168.15.1 This seems to work, I can ping or traceroute anything, browsers all work fine, firefox works fine. But sendmail does not send mail out to my ISP for some reason, I keep getting this lookup failure message in my maillog. Below is what message I am getting, can someone please help tell me what I am doing wrong and why I cannot send my mail out to the smart host anymore since changing my network and installing a new Linux OS? Feb 3 22:02:51 ohmster sendmail[2315]: o1432pCt002315: from= <ohmster(a)ohmster.com>, size=594, class=0, nrcpts=1, msgid= <1265252570.2244.0.camel(a)localhost>, proto=ESMTP, daemon=MTA, relay=localhost [127.0.0.1] Feb 3 22:03:32 ohmster sendmail[2318]: o1432pCt002315: to= <theohmster(a)comcast.net>, ctladdr=<ohmster(a)ohmster.com> (500/500), delay= 00:00:41, xdelay=00:00:40, mailer=relay, pri=120594, relay=smtp.comcast.net, dsn=4.0.0, stat=Deferred: Name server: smtp.comcast.net: host name lookup failure I give up and have to call in the experts (you). Thanks. -- ~Ohmster | ohmster59 /a/t/ gmail dot com Put "messageforohmster" in message body (That is Message Body, not Subject!) to pass my spam filter.
From: Andrzej Adam Filip on 4 Feb 2010 00:00 Ohmster <root(a)dev.nul.invalid> wrote: > This is killing me, I am trying so hard to make this work and I am > somehow missing something. I have sendmail setup to use my ISP as a smart > host, use port 587, and use auth. I think I have that all setup properly, > I used the settings from my prior sendmail setup that always worked. This > is a little different this time though. > > Before I had my modem setup to go directly to my Fedora box, then to a > hub, then to my local LAN. My Vonage router broke so I have a new one > they sent me, a Motorola VT-2542-VD, then to the Fedora 12 box. So now > the router is supply DHCP and it sets the resolv.conf file on my linux > box as such: > > [ohmster(a)ohmster ~]$ cat /etc/resolv.conf > # Generated by NetworkManager > nameserver 192.168.15.1 > > This seems to work, I can ping or traceroute anything, browsers all work > fine, firefox works fine. But sendmail does not send mail out to my ISP > for some reason, I keep getting this lookup failure message in my > maillog. Below is what message I am getting, can someone please help tell > me what I am doing wrong and why I cannot send my mail out to the smart > host anymore since changing my network and installing a new Linux OS? > > > Feb 3 22:02:51 ohmster sendmail[2315]: o1432pCt002315: from= > <ohmster(a)ohmster.com>, size=594, class=0, nrcpts=1, msgid= > <1265252570.2244.0.camel(a)localhost>, proto=ESMTP, daemon=MTA, > relay=localhost [127.0.0.1] > Feb 3 22:03:32 ohmster sendmail[2318]: o1432pCt002315: to= > <theohmster(a)comcast.net>, ctladdr=<ohmster(a)ohmster.com> (500/500), delay= > 00:00:41, xdelay=00:00:40, mailer=relay, pri=120594, > relay=smtp.comcast.net, dsn=4.0.0, stat=Deferred: Name server: > smtp.comcast.net: host name lookup failure > > I give up and have to call in the experts (you). Thanks. Push the message (by queue id) in verbose mode with DNS tracking turned on - It should provide more hints As root execute: sendmail -v -d8.20 -qIo1432pCt002315 -- [pl>en Andrew] Andrzej Adam Filip : anfi(a)onet.eu : Andrzej.Filip(a)gmail.com lawsuit, n.: A machine which you go into as a pig and come out as a sausage. -- Ambrose Bierce
From: Ohmster on 4 Feb 2010 00:50 Andrzej Adam Filip <anfi(a)onet.eu> wrote in news:3q7s1gzkrz-A24(a)andrea.huge.strangled.net: > Push the message (by queue id) in verbose mode with DNS tracking > turned on - It should provide more hints > > As root execute: > > sendmail -v -d8.20 -qIo1432pCt002315 Sure, need to find out what this is all about... [root(a)ohmster ~]# sendmail -v -d8.20 -qIo1432pCt002315 Running /var/spool/mqueue/o1432pCt002315 (sequence 1 of 1) dns_getcanonname(ohmster.com, trymx=1) dns_getcanonname: trying ohmster.com. (AAAA) NO: errno=0, h_errno=4 dns_getcanonname: trying ohmster.com. (A) YES dns_getcanonname: ohmster.com dns_getcanonname(comcast.net, trymx=1) dns_getcanonname: trying comcast.net. (AAAA) NO: errno=0, h_errno=4 dns_getcanonname: trying comcast.net. (A) YES dns_getcanonname: comcast.net getmxrr(smtp.comcast.net, droplocalhost=1) getmxrr: res_search(smtp.comcast.net) failed (errno=110, h_errno=2) <theohmster(a)comcast.net>... Deferred: Name server: smtp.comcast.net: host name lookup failure [root(a)ohmster ~]# [root(a)ohmster ~]# ping smtp.comcast.net PING smtp.g.comcast.net (76.96.62.117) 56(84) bytes of data. From 68.86.228.150 icmp_seq=24 Packet filtered ^C --- smtp.g.comcast.net ping statistics --- 38 packets transmitted, 0 received, +1 errors, 100% packet loss, time 44681ms [root(a)ohmster ~]# Well that's odd. My Windows machines use the exact same router and they have no problem at all reaching smpt.comcast.net. I even edited resolv.conf to my known nameservers but a reboot reset them back to a single nameserver, the router. What do you think this means Andrze? -- ~Ohmster | ohmster59 /a/t/ gmail dot com Put "messageforohmster" in message body (That is Message Body, not Subject!) to pass my spam filter.
From: Andrzej Adam Filip on 4 Feb 2010 01:32 Ohmster <root(a)dev.nul.invalid> wrote: > Andrzej Adam Filip <anfi(a)onet.eu> wrote in > news:3q7s1gzkrz-A24(a)andrea.huge.strangled.net: > >> Push the message (by queue id) in verbose mode with DNS tracking >> turned on - It should provide more hints >> >> As root execute: >> >> sendmail -v -d8.20 -qIo1432pCt002315 > > Sure, need to find out what this is all about... > > [root(a)ohmster ~]# sendmail -v -d8.20 -qIo1432pCt002315 > > Running /var/spool/mqueue/o1432pCt002315 (sequence 1 of 1) > dns_getcanonname(ohmster.com, trymx=1) > dns_getcanonname: trying ohmster.com. (AAAA) > NO: errno=0, h_errno=4 > dns_getcanonname: trying ohmster.com. (A) > YES > dns_getcanonname: ohmster.com > dns_getcanonname(comcast.net, trymx=1) > dns_getcanonname: trying comcast.net. (AAAA) > NO: errno=0, h_errno=4 > dns_getcanonname: trying comcast.net. (A) > YES > dns_getcanonname: comcast.net > getmxrr(smtp.comcast.net, droplocalhost=1) > > getmxrr: res_search(smtp.comcast.net) failed (errno=110, h_errno=2) > <theohmster(a)comcast.net>... Deferred: Name server: smtp.comcast.net: host > name lookup failure One more test: echo "/map host smtp.comcast.net" | sendmail -d8.20 -bt If it returns (errno=110, h_errno=2) in response to AAAA lookup then try to fix it by adding the following line to your sendmail.mc define(`confBIND_OPTS', `WorkAroundBrokenAAAA')dnl [ http://linux.derkeiler.com/Mailing-Lists/Fedora/2004-11/3170.html ] > [root(a)ohmster ~]# ping smtp.comcast.net > PING smtp.g.comcast.net (76.96.62.117) 56(84) bytes of data. > From 68.86.228.150 icmp_seq=24 Packet filtered > ^C > --- smtp.g.comcast.net ping statistics --- > 38 packets transmitted, 0 received, +1 errors, 100% packet loss, time > 44681ms Some sites block pings (the relevant icmp packets). Can you telnet msa port on the host? telnet smtp.comcast.net 587 > Well that's odd. My Windows machines use the exact same router and they > have no problem at all reaching smpt.comcast.net. I even edited > resolv.conf to my known nameservers but a reboot reset them back to a > single nameserver, the router. > > What do you think this means Andrzej? Check if WorkAroundBrokenAAAA can fix it. -- [pl>en Andrew] Andrzej Adam Filip : anfi(a)onet.eu : Andrzej.Filip(a)gmail.com Open-Sendmail: http://open-sendmail.sourceforge.net/ In the strict scientific sense we all feed on death -- even vegetarians. -- Spock, "Wolf in the Fold", stardate 3615.4
From: Ohmster on 4 Feb 2010 12:35
Andrzej Adam Filip <anfi(a)onet.eu> wrote in news:1fsdevqry6-A24(a)eileen.huge.strangled.net: [..] > One more test: Okay, here goes... > echo "/map host smtp.comcast.net" | sendmail -d8.20 -bt [root(a)ohmster ~]# echo "/map host smtp.comcast.net" | sendmail -d8.20 -bt ADDRESS TEST MODE (ruleset 3 NOT automatically invoked) Enter <ruleset> <address> > map_lookup: host (smtp.comcast.net) dns_getcanonname(smtp.comcast.net, > trymx=1) dns_getcanonname: trying smtp.comcast.net. (AAAA) YES dns_getcanonname: trying smtp.g.comcast.net. (AAAA) NO: errno=0, h_errno=4 dns_getcanonname: trying smtp.g.comcast.net. (A) YES dns_getcanonname: smtp.g.comcast.net returns smtp.g.comcast.net. (0) > [root(a)ohmster ~]# > If it returns (errno=110, h_errno=2) in response to AAAA lookup then > try to fix it by adding the following line to your sendmail.mc > define(`confBIND_OPTS', `WorkAroundBrokenAAAA')dnl > > [ http://linux.derkeiler.com/Mailing-Lists/Fedora/2004-11/3170.html ] > [..] > > Some sites block pings (the relevant icmp packets). > Can you telnet msa port on the host? > > telnet smtp.comcast.net 587 > Will try it now... [..] >> >> What do you think this means Andrzej? > > Check if WorkAroundBrokenAAAA can fix it. Trying to reach server with telnet on port 587: > [root(a)ohmster ~]# telnet smtp.comcast.net 587 Trying 76.96.62.117... Connected to smtp.comcast.net. Escape character is '^]'. 220 omta20.westchester.pa.mail.comcast.net comcast ESMTP server ready HELO ohmster.com 250 omta20.westchester.pa.mail.comcast.net hello [174.48.12.44], pleased to meet you quit 221 2.0.0 omta20.westchester.pa.mail.comcast.net comcast closing connection Connection closed by foreign host. You have mail in /var/spool/mail/root [root(a)ohmster ~]# I do not get error returns of (errno=110, h_errno=2) in response to AAAA lookup, so does this means that the WorkAroundBrokenAAAA will not apply here? This is so cryptic, what does it all mean? Since getting dovecot to work with sendmail, I am now receiving email on my Windows machine from the Linux machine like this now (I tried to send a test mail ito myself at my ISP from Evolution): ********************************************** ** THIS IS A WARNING MESSAGE ONLY ** ** YOU DO NOT NEED TO RESEND YOUR MESSAGE ** ********************************************** The original message was received at Wed, 3 Feb 2010 22:02:51 -0500 from localhost [127.0.0.1] ----- Transcript of session follows ----- <theohmster(a)comcast.net>... Deferred: Name server: smtp.comcast.net: host name lookup failure Warning: message still undelivered after 4 hours Will keep trying until message is 5 days old What do you think Andrzej or anybody? I really want to resolve this but am not sure where to go at this point. Thank you very much for your sincere help, Andrzej. -- ~Ohmster | ohmster59 /a/t/ gmail dot com Put "messageforohmster" in message body (That is Message Body, not Subject!) to pass my spam filter. |