I have postfix 2.6.6 on centos 6, in use about 1 year, no known issues couple of weeks ago struck a problem unable to deliver email to any user on domain "pinewood.ie" with "A record/host not found" (1):
pinewood.ie mx are on cleanmail02.cdsoft.ie/cleanmail01.cdsoft.ie tried putting MX IP/hostname in /etc/hosts, doesn't seem to help: host hostname segfaults (see below) dig +trace fails (see below) I'm not sure what to try...? or, what to ask remote side to do/try/test ? is this some sort of ipv4/ipv6 issue maybe ?? people at pinewood.ie tell me all's well at their end...? telnet to ip:25 works OK # cat hosts 127.0.0.1 localhost.localdomain localhost4 localhost4.localdomain4localhost ::1 localhost6 localhost6.localdomain6 89.28.178.25 cleanmail01.cdsoft.ie 89.28.178.26 cleanmail02.cdsoft.ie trying to resolve it get: # host cleanmail02.cdsoft.ie ;; connection timed out; trying next origin Segmentation fault (core dumped) dig trace fails (see below) I can telnet to ip:25 address OK, not to hostname:25 telnet 89.28.178.25 25 Trying 89.28.178.25... Connected to 89.28.178.25. Escape character is '^]'. 220 Welcome To CDSofts Cleanmail02 Service - Ready to receive mail -=- ESMTP ehlo me.com 250-Welcome To CDSofts Cleanmail02 Service - Ready to receive mail -=- 250-AUTH LOGIN PLAIN 250-AUTH=LOGIN PLAIN 250-PIPELINING 250 8BITMIME # telnet cleanmail02.cdsoft.ie 25 telnet: cleanmail02.cdsoft.ie: Name or service not known cleanmail02.cdsoft.ie: Host name lookup failure 1.-------------------- -Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient------- EAB18382A0C 1272 Sat Mar 2 13:04:00 voy...@sbt.net.au (Host or domain name not found. Name service error for name=cleanmail02.cdsoft.ie type=A: Host not found, try again) x...@pinewood.ie dig mx pinewood.ie ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.10.rc1.el6_3.6 <<>> mx pinewood.ie ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 61283 ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;pinewood.ie. IN MX ;; ANSWER SECTION: pinewood.ie. 2541 IN MX 10 cleanmail01.cdsoft.ie. pinewood.ie. 2541 IN MX 20 cleanmail02.cdsoft.ie. ;; Query time: 1724 msec ;; SERVER: 180.235.130.244#53(180.235.130.244) ;; WHEN: Sat Mar 2 13:21:42 2013 ;; MSG SIZE rcvd: 92 ======================== # dig a cleanmail02.cdsoft.ie +trace ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.10.rc1.el6_3.6 <<>> a cleanmail02.cdsoft.ie +trace ;; global options: +cmd . 97783 IN NS b.root-servers.net. . 97783 IN NS k.root-servers.net. . 97783 IN NS e.root-servers.net. . 97783 IN NS f.root-servers.net. . 97783 IN NS h.root-servers.net. . 97783 IN NS c.root-servers.net. . 97783 IN NS a.root-servers.net. . 97783 IN NS l.root-servers.net. . 97783 IN NS m.root-servers.net. . 97783 IN NS j.root-servers.net. . 97783 IN NS d.root-servers.net. . 97783 IN NS g.root-servers.net. . 97783 IN NS i.root-servers.net. ;; Received 449 bytes from 180.235.130.244#53(180.235.130.244) in 1585 ms ie. 172800 IN NS a.iedr.ie. ie. 172800 IN NS b.iedr.ie. ie. 172800 IN NS c.iedr.ie. ie. 172800 IN NS d.iedr.ie. ie. 172800 IN NS ns3.ns.esat.net. ie. 172800 IN NS gns1.domainregistry.ie. ie. 172800 IN NS gns2.domainregistry.ie. ie. 172800 IN NS ns-ie.nic.fr. ;; Received 428 bytes from 193.0.14.129#53(193.0.14.129) in 2781 ms cdsoft.ie. 172800 IN NS ns1.cdsoft-irl.net. cdsoft.ie. 172800 IN NS ns2.cdsoft-irl.net. ;; Received 89 bytes from 192.93.0.4#53(192.93.0.4) in 10352 ms ;; connection timed out; no servers could be reached