>Why should'nt Imail try the secondary mailservers if it get a 421?? >According to RFC821 the 421 error means: >421 <domain> Service not available, > closing transmission channel
the service is not available to anybody, including the backup MX servers if your MTA sends to the backup MX servers. >I thought that a secondary mailservers should be used in cases where >"<domain> Service not available", no, where the SMTP service is not available. domain name service is not the issue. > why should I bother setting up a baskup >server if it's only used when "<domain> Service is available" :-) Get my >point?? yes, but you've made up your own <point>. >The ISP that I have the problem with, explained that the DNS setup was made >that way because their secondary mailservers is the only servers that is >allowed to send mail to the primary mailserver (security isue), so all >mailconnections is refused at the primary, accepted at the secondary and >forwarded to the primary from the secondary. They are a huge ISP in Denmark >and according to them a lot of others isp's has the same config ok, ask him to give us a list of these isp's. If his mail server does not accept SMTP connections on port 25 from internet, it should not be listed as an MX host. There something fishy in .dk. Len http://MenAndMice.com/DNS-training http://BIND8NT.MEIway.com : ISC BIND for NT4 & W2K http://IMGate.MEIway.com : Build free, hi-perf, anti-abuse mail gateways Please visit http://www.ipswitch.com/support/mailing-lists.html to be removed from this list. An Archive of this list is available at: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/
