On Mon, Aug 23, 2010 at 11:08 AM, Gabriel Tabares <gabriel.tabares@xxxxxxxxxxxx> > One more thing, if this is the case, why does the nslookup respond > straight away? Is the destination server trying to somehow validate the > host where the connection came from? It's entirely possible (and probable) that the mail server is attempting to do a reverse looking up the originating host. When the lookup times out, the connection goes through. If the command ping my-mail02.mydomain.com returns immediately with data, that would support that theory. M _______________________________________________ CentOS mailing list CentOS@xxxxxxxxxx http://lists.centos.org/mailman/listinfo/centos