One of our clients has an in-house Postfix mailserver which basically
downloads mail for the individual users from our mail server hosted on
the web using fetchmail.
They use our SMTP server to send mail. Their email clients are then
setup to get & send mail from the server, on 192.168.2.254 (for POP3 &
SMTP). All mail between them on the local LAN gets send to each other
via the server, and not the internet.
This works quite well, but as soon as someone sends mail from the
Linux server directly (it has webmin + usermin installed and has a
basic webmail interface for when they’re out of the office) it sends
mail using the local machine name, instead of the domain name.
for example, mail comes from esther@ser001.rewards.local.
How do I tell Postfix to automaticlly send mail from
@<theirdomain.com> instead?
Sorry for asking this, but I don’t know Postfix very well and don’t
know what to call to, to search on google.
Ah, I bet you’re not using Virtualmin on that system, are you… Virtualmin would automatically add those entries for you. But, if you’re simply adding users to the server via Webmin or on the command line, that wouldn’t populate the virtual file.
In that case, you may actually find RoundCube simpler, as you can easily set the “From” address for each account.
Otherwise, you’d need to make sure you populate the virtual file each time a user is added to the system… or install Virtualmin, and use it to add your users to the server.