I hate to be that guy, but "it works for me"... dig umd.edu MX
; <<>> DiG 9.3.2 <<>> umd.edu MX ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 7029 ;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 3, ADDITIONAL: 2 ;; QUESTION SECTION: ;umd.edu. IN MX ;; ANSWER SECTION: umd.edu. 15875 IN MX 10 mailfw2.umd.edu. umd.edu. 15875 IN MX 10 mailfw0.umd.edu. umd.edu. 15875 IN MX 10 mailfw1.umd.edu. ;; AUTHORITY SECTION: umd.edu. 15442 IN NS noc.umd.edu. umd.edu. 15442 IN NS ns1.umd.edu. umd.edu. 15442 IN NS ns2.umd.edu. ;; ADDITIONAL SECTION: noc.umd.edu. 120 IN A 128.8.5.2 ns2.umd.edu. 59974 IN A 128.8.76.2 ;; Query time: 7 msec ;; SERVER: 192.168.0.1#53 (192.168.0.1) ;; WHEN: Mon Jan 15 19:24:39 2007 ;; MSG SIZE rcvd: 183 host -a gives the same result. I'm not certain how to do it with host, but run a DNS trace. I use dig, so it's "dig umd.edu MX +trace". It'll run the DNS iterations from the root servers itself and show you the results. I get the following: [EMAIL PROTECTED] ~ $ dig umd.edu MX +trace ; <<>> DiG 9.3.2 <<>> umd.edu MX +trace ;; global options: printcmd . 41653 IN NS A.ROOT-SERVERS.NET. . 41653 IN NS B.ROOT-SERVERS.NET. . 41653 IN NS C.ROOT-SERVERS.NET. . 41653 IN NS D.ROOT-SERVERS.NET. . 41653 IN NS E.ROOT-SERVERS.NET. . 41653 IN NS F.ROOT-SERVERS.NET. . 41653 IN NS G.ROOT-SERVERS.NET. . 41653 IN NS H.ROOT-SERVERS.NET. . 41653 IN NS I.ROOT-SERVERS.NET. . 41653 IN NS J.ROOT-SERVERS.NET. . 41653 IN NS K.ROOT-SERVERS.NET. . 41653 IN NS L.ROOT-SERVERS.NET. . 41653 IN NS M.ROOT-SERVERS.NET. ;; Received 436 bytes from 192.168.0.1#53(192.168.0.1) in 7 ms edu. 172800 IN NS L3.NSTLD.COM . edu. 172800 IN NS D3.NSTLD.COM. edu. 172800 IN NS A3.NSTLD.COM. edu. 172800 IN NS E3.NSTLD.COM. edu. 172800 IN NS C3.NSTLD.COM. edu. 172800 IN NS G3.NSTLD.COM. edu. 172800 IN NS M3.NSTLD.COM. edu. 172800 IN NS H3.NSTLD.COM. ;; Received 298 bytes from 198.41.0.4#53(A.ROOT-SERVERS.NET) in 15 ms umd.edu. 172800 IN NS NS2.umd.edu. umd.edu. 172800 IN NS NOC.umd.edu. umd.edu. 172800 IN NS NS1.umd.edu . ;; Received 127 bytes from 192.41.162.32#53(L3.NSTLD.COM) in 27 ms umd.edu. 60000 IN MX 10 mailfw1.umd.edu. umd.edu. 60000 IN MX 10 mailfw2.umd.edu. umd.edu. 60000 IN MX 10 mailfw0.umd.edu. umd.edu. 60000 IN NS ns2.umd.edu. umd.edu. 60000 IN NS noc.umd.edu. umd.edu. 60000 IN NS ns1.umd.edu. ;; Received 247 bytes from 128.8.76.2#53( NS2.umd.edu) in 16 ms It's a good tool to figure out where the failure point is, plus it doesn't use your ISP's DNS servers, so it'll tell you if it's just an issue with them. Also, another option with dig is "dig umd.edu MX @<some dns server>" so you can query individual DNS servers. You might also use that to query your suspected failure points. So, in order to check what each of your ISP's DNS servers are returning, use: cat /etc/resolv.conf | grep nameserver | sed s/nameserver\\s*// | xargs -I ns dig umd.edu MX @ns Good luck! ~John On 1/15/07, Judah Milgram <[EMAIL PROTECTED]> wrote:
Nope, no mx records here, see below. I'm not even sure what nameserver I'm using because this is DHCP to some broadband service. Comcast, I think (wireless at a friend's house). Probably that's the source of the broken-ness. The other question is why fetchmail flushes mail off the server if local sendmail won't take it. Probably a feature not a bug but still, seems pretty harmful default behavior. I just lost two critical emails. mite:~: host -a umd.edu Trying "umd.edu" Host umd.edu not found: 4(NOTIMP) Received 25 bytes from 192.168.0.1#53 in 21 ms Judah Daniel Carter <[EMAIL PROTECTED]> wrote: > There is not an actual hostname for umd.edu assigned for a variety of > reasons, but there are MX records for umd.edu which is why everything works > fine. I have not seen a mailer before reject mail for this reason. If you > do a host -a you will see the MX records for it. > > -----Original Message----- > From: UM Linux User's Group [mailto:[EMAIL PROTECTED] On Behalf Of > Judah Milgram > Sent: Monday, January 15, 2007 8:58 AM > To: [email protected] > Subject: [UM-LINUX] "umd.edu" doesn't resolve? > > very odd thing ... I just lost two emails from someone with an [EMAIL PROTECTED] > address > because sendmail couldn't resolve his domain: (name x'd to protect the > innocent) > > reading message [EMAIL PROTECTED]:3 of 23 (2354 header octets) > ..fetchmail: SMTP error: 553 5.1.8 <[EMAIL PROTECTED]>... Domain of sender > address [EMAIL PROTECTED] does not exist > flushed > reading message [EMAIL PROTECTED]:4 of 23 (2327 header octets) > ..fetchmail: SMTP error: 553 5.1.8 <[EMAIL PROTECTED] >... Domain of sender > address [EMAIL PROTECTED] does not exist > flushed > > a quick check: > > mite:~: host umd.edu > Host umd.edu not found: 3(NXDOMAIN) > > and verified it on another machine. That's can't be right - or?! Anyone > else having this sort of problem? Meanwhile, I turned on > accept_unresolvable_domains. > > Judah >
