curious DNS behavior (slow?) and related sendmail bug

Linda W bind at tlinx.org
Tue Sep 16 18:07:23 UTC 2003


looking for MX list for groups.queernet.org....(trying to debug a sendmail
problem that returns errors like this:

---------------- (if anyone has a clue or has seen sendmail do this before,
please email me OL...I'm going crazy^hier)
The original message was received at Sun, 14 Sep 2003 16:08:51 -0700
from shiva [192.168.3.20]

  ----- The following addresses had permanent fatal errors -----
<bind at isc.org>

  ----- Transcript of session follows -----
550 5.1.2 <bind at isc.org>... Host unknown (Name server: mx-2.isc.org.: host not found)



Reporting-MTA: dns; ishtar.tlinx.org
Received-From-MTA: DNS; shiva
Arrival-Date: Sun, 14 Sep 2003 16:08:51 -0700

Final-Recipient: RFC822; bind at isc.org
Action: failed
Status: 5.1.2
Remote-MTA: DNS; mx-2.isc.org
Last-Attempt-Date: Sun, 14 Sep 2003 16:08:51 -0700
----------------

So tried using sendmail from cmd line -- got same message as above (except
for "queernet") (little did they know, they were being used as my test
subject! :-))

My going back to basics attempt was to try to submit the email directly to
their MX machine and see if that took a post (it did), but along the way
to the "forum"....I encountered some wierd time delays in getting MX
information.  Note locally, I get no return MX record.


    ishtar:# dig -t MX groups.queernet.org

        ; <<>> DiG 9.2.2 <<>> -t MX groups.queernet.org
        ;; global options:  printcmd
        ;; Got answer:
        ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 44892
        ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

        ;; QUESTION SECTION:
        ;groups.queernet.org.           IN      MX

        ;; AUTHORITY SECTION:
        queernet.org.           250     IN      SOA     onlinepolicy.org. hostmaster.onlinepolicy.org. 2000011254 14400 3600 1728000 14400

        ;; Query time: 7 msec
        ;; SERVER: 127.0.0.1#53(127.0.0.1)
        ;; WHEN: Tue Sep 16 08:56:20 2003
        ;; MSG SIZE  rcvd: 97

Trying my ISP's name server and it's worse:

    ishtar:# dig @ns1.speakeasy.net -t MX groups.queernet.org   

        ; <<>> DiG 9.2.2 <<>> @ns1.speakeasy.net -t MX groups.queernet.org
        ;; global options:  printcmd
        ;; connection timed out; no servers could be reached
    ishtar:# dig @ns.speakeasy.net -t MX groups.queernet.org 
        dig: Couldn't find server 'ns.speakeasy.net': Name or service not known
    ishtar:# dig @ns1.speakeasy.net -t MX queernet.org       

        ; <<>> DiG 9.2.2 <<>> @ns1.speakeasy.net -t MX queernet.org
        ;; global options:  printcmd
        ;; connection timed out; no servers could be reached
    ishtar:# dig @ns1.speakeasy.net -t A queernet.org  

        ; <<>> DiG 9.2.2 <<>> @ns1.speakeasy.net -t A queernet.org
        ;; global options:  printcmd
        ;; connection timed out; no servers could be reached


But yes -- my nameserver (doesn't use their name server, I tie in through
the root servers) at least knows about the site

    ishtar:# dig -t A queernet.org

        ; <<>> DiG 9.2.2 <<>> -t A queernet.org
        ;; global options:  printcmd
        ;; Got answer:
        ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 45939
        ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 5, ADDITIONAL: 5

        ;; QUESTION SECTION:
        ;queernet.org.                  IN      A

        ;; ANSWER SECTION:
        queernet.org.           300     IN      A       64.62.161.196

        ;; AUTHORITY SECTION:
        queernet.org.           300     IN      NS      ns1.everydns.net.
        queernet.org.           300     IN      NS      ns2.everydns.net.
        queernet.org.           300     IN      NS      ns2.onlinepolicy.net.
        queernet.org.           300     IN      NS      ns3.everydns.net.
        queernet.org.           300     IN      NS      ns4.everydns.net.

        ;; ADDITIONAL SECTION:
        ns1.everydns.net.       104158  IN      A       209.75.39.141
        ns2.everydns.net.       104158  IN      A       216.218.240.206
        ns2.onlinepolicy.net.   104158  IN      A       64.62.161.193
        ns3.everydns.net.       104158  IN      A       81.17.40.70
        ns4.everydns.net.       104158  IN      A       63.219.183.200

        ;; Query time: 16 msec
        ;; SERVER: 127.0.0.1#53(127.0.0.1)
        ;; WHEN: Tue Sep 16 08:59:23 2003
        ;; MSG SIZE  rcvd: 241

    ishtar:# dig +trace @ns.speakyeasy.net -t ANY queernet.org        

        ; <<>> DiG 9.2.2 <<>> +trace @ns.speakyeasy.net -t ANY queernet.org
        ;; global options:  printcmd
        ;; connection timed out; no servers could be reached

ISP NS still doesn't even know who they are....
but now...using dig with a +trace....and I get the MX record.  Slight
sidenote -- why would "ANY" not return any "A" records?  But it did 
return the NS/MX records.  I though (perhaps erroneously) that ANY meant
return ANY record found -- or "ALL" records (including "A")?


    ishtar:# dig +trace  -t ANY queernet.org                  

        ; <<>> DiG 9.2.2 <<>> +trace -t ANY queernet.org
        ;; global options:  printcmd
        .                       448592  IN      NS      I.ROOT-SERVERS.NET.
        .                       448592  IN      NS      J.ROOT-SERVERS.NET.
        .                       448592  IN      NS      K.ROOT-SERVERS.NET.
        .                       448592  IN      NS      L.ROOT-SERVERS.NET.
        .                       448592  IN      NS      M.ROOT-SERVERS.NET.
        .                       448592  IN      NS      A.ROOT-SERVERS.NET.
        .                       448592  IN      NS      B.ROOT-SERVERS.NET.
        .                       448592  IN      NS      C.ROOT-SERVERS.NET.
        .                       448592  IN      NS      D.ROOT-SERVERS.NET.
        .                       448592  IN      NS      E.ROOT-SERVERS.NET.
        .                       448592  IN      NS      F.ROOT-SERVERS.NET.
        .                       448592  IN      NS      G.ROOT-SERVERS.NET.
        .                       448592  IN      NS      H.ROOT-SERVERS.NET.
        ;; Received 436 bytes from 127.0.0.1#53(127.0.0.1) in 1 ms

        org.                    172800  IN      NS      TLD1.ULTRADNS.NET.
        org.                    172800  IN      NS      TLD2.ULTRADNS.NET.
        ;; Received 112 bytes from 192.36.148.17#53(I.ROOT-SERVERS.NET) in 158 ms

        queernet.org.           86400   IN      NS      ns4.everydns.net.
        queernet.org.           86400   IN      NS      ns3.everydns.net.
        queernet.org.           86400   IN      NS      ns2.onlinepolicy.net.
        queernet.org.           86400   IN      NS      ns2.everydns.net.
        queernet.org.           86400   IN      NS      ns1.everydns.net.
        ORG.                    86400   IN      NS      TLD2.ULTRADNS.NET.
        ORG.                    86400   IN      NS      TLD1.ULTRADNS.NET.
        ;; Received 230 bytes from 204.74.113.1#53(TLD2.ULTRADNS.NET) in 172 ms

    ishtar:# dig +trace  -t MX queernet.org   

        ; <<>> DiG 9.2.2 <<>> +trace -t MX queernet.org
        ;; global options:  printcmd
        .                       448579  IN      NS      F.ROOT-SERVERS.NET.
        .                       448579  IN      NS      G.ROOT-SERVERS.NET.
        .                       448579  IN      NS      H.ROOT-SERVERS.NET.
        .                       448579  IN      NS      I.ROOT-SERVERS.NET.
        .                       448579  IN      NS      J.ROOT-SERVERS.NET.
        .                       448579  IN      NS      K.ROOT-SERVERS.NET.
        .                       448579  IN      NS      L.ROOT-SERVERS.NET.
        .                       448579  IN      NS      M.ROOT-SERVERS.NET.
        .                       448579  IN      NS      A.ROOT-SERVERS.NET.
        .                       448579  IN      NS      B.ROOT-SERVERS.NET.
        .                       448579  IN      NS      C.ROOT-SERVERS.NET.
        .                       448579  IN      NS      D.ROOT-SERVERS.NET.
        .                       448579  IN      NS      E.ROOT-SERVERS.NET.
        ;; Received 436 bytes from 127.0.0.1#53(127.0.0.1) in 1 ms

        org.                    172800  IN      NS      TLD2.ULTRADNS.NET.
        org.                    172800  IN      NS      TLD1.ULTRADNS.NET.
        ;; Received 112 bytes from 192.5.5.241#53(F.ROOT-SERVERS.NET) in 31 ms

        queernet.org.           86400   IN      NS      ns4.everydns.net.
        queernet.org.           86400   IN      NS      ns3.everydns.net.
        queernet.org.           86400   IN      NS      ns2.onlinepolicy.net.
        queernet.org.           86400   IN      NS      ns2.everydns.net.
        queernet.org.           86400   IN      NS      ns1.everydns.net.
        ;; Received 145 bytes from 204.74.113.1#53(TLD2.ULTRADNS.NET) in 259 ms

        queernet.org.           300     IN      MX      20 mailbox.onlinepolicy.net.
        queernet.org.           300     IN      NS      ns1.everydns.net.
        queernet.org.           300     IN      NS      ns2.everydns.net.
        queernet.org.           300     IN      NS      ns2.onlinepolicy.net.
        queernet.org.           300     IN      NS      ns3.everydns.net.
        queernet.org.           300     IN      NS      ns4.everydns.net.
        ;; Received 329 bytes from 63.219.183.200#53(ns4.everydns.net) in 74 ms


I actually "missed" the MX record and sent the emaill by telnetting to
the sendmail socket and speaking SMPTese (very rusty) on groups.queernet.net
and that did accept the email -- might be a pseudo for
mailbox.onlinepolicy.net...dunno.
But 10 minutes later...my ISP also had fetched and "knew" the A, NS and MX
records.

If a normal program ran and was using my ISP's name server as its sole
addr resolution service, wouldn't the email have just returned to me
instantly as 'host not found' Or would a normal email program have
detected the "timeout" and just retried in 5-10 minutes?  It seems it
certainly would slow down interactive web-browsing to have to wait 5 minutes
for a name lookup to complete.

Still dunno why my sendmail isn't talking to other sendmail's though. It
used to work, but been trying to debug an outlook problem -- when I downloaded
the patch for the MS-blaster worm in July, I didn't get worm, but I did
get the patch --- which disabled outlook from being able to read email
of my local IMAP server (which, I suppose, is one way of preventing
email viruses 'cept blaster was port 135).  Mozilla, of course, can still
read emails, but it seems to be affected by my sendmail problem I've
managed to create along the way (lucky me).  Not sure how -- not the best
focus on debugging, and trying too many random things (pain meds I'm on for
RSI disability problems/pain).

Will probably send this same way -- talk to iscs.org's MX server...become
an efficient sendmail deamon -- objective in life?...sigh

-Linda

p.s. If I don't respond, don't take it personally, it's really a pain to
do manual sendmail via telnetting to remote system.




More information about the bind-users mailing list