I've recently had some of my customers emailing me large image attachments and my Postfix mail server has been rejecting them. A quick look at the postfix configuration showed the message size limit … [Read more...] about Changing the Postfix maximum email size
Information And Howtos About Email Servers Such As Postfix, Dovecot, Maildrop, Sendmail
Email was the first "killer app" of the early Internet and today millions of emails are sent every day using a variety of emails servers such as postfix and sendmail. This section looks at how to use and configure email servers for sending and receiving email, mail filtering with services such as maildrop and procmail, and POP and IMAP servers such as Courier IMAP and Dovecot.
I have been in the process of migrating my websites from a couple of dedicated machines to a VPS (Virtual Private Server) which has a fairly minimal base install of CentOS 5 on it. My existing … [Read more...] about Installing maildrop on CentOS 5
Postfix by default on CentOS 5 and Red Hat Enterprise Linux is configured to only receive mail on the local network interface. This is good if you are not intending your server to run as a mail server … [Read more...] about Configure postfix to accept mail from external connections
The RedHat distribution of Linux often misconfigures the /etc/hosts file which can prevent Sendmail from working correctly. This may also affect other Linux distributions, but my main experience is … [Read more...] about Sendmail Connection Refused on localhost
If you are having problems connecting to sendmail, postfix or other mail servers remotely it may either be a sendmail configuration issue or a firewall issue. The Linux 2.4 and greater kernel comes … [Read more...] about Opening port 25 for mail servers with iptables
If you can connect to sendmail locally but not remotely then you need to modify the sendmail configuration slightly. For normal workstation use, you would not want sendmail to be opened up for remote … [Read more...] about Sendmail remote connection refused