Well, I live in the land of "sendmail familiar", but quite a distance from "sendmail guru". All I've ever done is put the domain for the email in /etc/mail/relay-domains and restart sendmail. EG: If host is a backup relay for snafoo.com, type "snafoo.com" in a line all by itself in /etc/mail/relay-domains. It takes it from there. If the primary host goes down for > 4 hours, senders start getting notice messages. If primary host goes down for > 48 hours, senders start getting "undeliverable" messages back. -Ben On Wednesday 11 January 2006 23:01, Mohd Ikhwan Bin Abdullah wrote: > I would like to know is there anyone who know how to or a site with the how > to on configuring a sendmail box to queue the mail only when the primary > mail server is down. And when the primary mail server is up it will issue an > ETRN command to the queue server to start processing and pushing the mail > that is queued to the primary server. > > I am very much aware about the MX record priority on the DNS server but just > need to configure the secondary mail server only. > > Thank you. > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos > -- "The best way to predict the future is to invent it." - XEROX PARC slogan, circa 1978