Hi Dominic, what's wrong with that?
global operating companies do that for a good reason. they use geoIP on your client address to figure out the nearest server for you and put it into the reply to your request. you will be able to connect with much less latency than connecting to another server on another continent sometimes dns is also used to achive some kind of loadbalancing - just to keep in mind ;-) cheers Ralph ----- Am 16. Sep 2019 um 15:51 schrieb Dominic Schlegel [email protected]: > Hi All > > We are experiencing problems delivering mails for domains having their MX > record > set to mx-eu.mail.am0.yahoodns.net (for example yahoo.it, yahoo.de, > yahoo.co.uk). So far we have figured out that Yahoo’s DNS servers send > different responses. Depending on the DNS response we are able to establish > SMTP connections. Below example shows 2 servers from their DNS that seems to > accept SMTP connections: > > [root@x1:~] # dig a mx-eu.mail.am0.yahoodns.net @yf2.yahoo.com +short > 188.125.72.73 > 188.125.72.74 > > [root@x1:~] # telnet 188.125.72.73 25 > Trying 188.125.72.73... > Connected to mtaproxy1.free.mail.vip.ir2.yahoo.com. > > [root@x1:~] # telnet 188.125.72.74 25 > Trying 188.125.72.74... > Connected to mtaproxy2.free.mail.vip.ir2.yahoo.com. > > On the other hand we sometimes get other replies from the “same” (the > id.server > chaos record tell’s us it’s a different one) DNS server with different A > records that do not accept SMTP connections: > > [root@x1:~] # dig a mx-eu.mail.am0.yahoodns.net @yf2.yahoo.com +short > 188.125.73.87 > 212.82.101.46 > > [root@x1:~] # telnet 188.125.73.87 25 > Trying 188.125.73.87... > telnet: connect to address 188.125.73.87: Operation timed out > telnet: Unable to connect to remote host > > [root@x1:~] # telnet 212.82.101.46 25 > Trying 212.82.101.46... > telnet: connect to address 212.82.101.46: Operation timed out > telnet: Unable to connect to remote host > > > We have so far confirmed this behaviour from different AS (Hetzer, OVH). Does > anybody else experiencing the same behaviour? > > We have tried to contact their postmaster address and few others we found on > the > internet. Unfortunately so far no one was really able to help us. The Yahoo > Small Business Phone Number that has been posted on this list back in October > 2009 seems no longer to be in operations too. Therefore if you know how to get > in touch with their technical staff that would be much appreciated. > > > Best Regards > Dominic Schlegel > > > > _______________________________________________ > swinog mailing list > [email protected] > http://lists.swinog.ch/cgi-bin/mailman/listinfo/swinog _______________________________________________ swinog mailing list [email protected] http://lists.swinog.ch/cgi-bin/mailman/listinfo/swinog
