Wietse Venema: > ram: > > > > On Mon, 2010-01-25 at 14:43 +0100, Emmanuel Seyman wrote: > > > > > * ram [25/01/2010 14:41] : > > > > > > > > All mails are sent by a postfix server and this box has to relay the > > > > mails to 3 load balanced machines. > > > > No windows machines in the picture at all > > > > > > What is the DNS server? On what OS is it running? > > > > > > > The DNS server is bind 9.5x > > I did an analysis , of 20k mails in the past hour 12k mails hit 1 server > > and the others got 5k and 3k each > > Postfix will randomize DNS results *only* if you haven't changed > the following (in main.cf or master.cf): > > smtp_host_lookup > disable_dns_lookups
Add here: smtp_randomize_addresses > Otherwise, many systems will return only one IP address. > > What is the "postconf -n" output and master.cf entry for the SMTP > client? > > Wietse > >