Dear John, Thanks for your response. good information provided. Thanks / Regards > On 04/12/12 4:35 AM, Peter Peltonen wrote: >> $ host 205.234.223.198 >> 198.223.234.205.in-addr.arpa domain name pointer mx4.servershost.net. >> >> $ host mx4.servershost.net >> mx4.servershost.net has address 66.225.237.241 >> >> As you can see the DNS resolves to different IP address than given by >> the PTR record. Some email systems consider this as an indication of a >> misconfigured mail server (spam sending attempt) and refuse to relay. > > except, thats the receiving server, and it shouldn't be rejecting itself. > > $ host -t MX tata-nigeria.com > tata-nigeria.com mail is handled by 30 mx4.servershost.net. > tata-nigeria.com mail is handled by 10 mx2.servershost.net. > tata-nigeria.com mail is handled by 20 mx3.servershost.net. > $ host mx4.servershost.net > mx4.servershost.net has address 66.225.237.241 > > the host is probably dualhomed, and that 66 IP matches the reverse... > > $ host 66.225.237.241 > 241.237.225.66.in-addr.arpa domain name pointer mx4.servershost.net. > > servershost.net appears to be a US based hosting company, yet their > WHOIS data is shrouded, and they dont have any websites at that domain > name, further > http://rbls.org/servershost.net > says they are broken, and have no postmaster or abuse alias as required > by the internet RFCs. > > > > > > -- > john r pierce N 37, W 122 > santa cruz ca mid-left coast > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos > Thanks / Regards Prabhpal S. Mavi