Qmail: routing all mails to a smarthost
# echo ":smtp.qmail.com" > /var/qmail/control/smtproutes
(or manually add “:smtp.qmail.com” line (without qutoes) to the file.) this command will set qmail that all your mails will be routed to smtp.qmail.com (will remove other existing lines, so be careful)
Qmail: routing all mails for a specific domain to a smarthost
# echo "domain.com:smtp.qmail.com" >> /var/qmail/control/smtproutes
this command will append a line to your smtproutes instructing qmail to send all mails @domain.com to smtp.qmail.com (rest of the lines will be kept).
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