Tag: exim
Adding sa-exim to Exim
Until now I have been using SpamAssassin using the spam content scanning built into Exim. This gives me detailed control over what happens to messages. However, I decided I wanted to review the messages that are rejected. Looking at my options sa-exim appeared to be a simple solution. I found it was as simple as…
Securing Submisssion on Exim
I noticed a significant increase in the number of hosts attempting to authenticate to my Exim submission ports (465 and 587). As a result, I have implemented a number of security measures. These measures have effectively blocked the attempts. This post outlines the main measures that I have implemented. This includes ACLs and fail2ban blacklisting.
Securing TLS
A StackExchange question on using HAProxy’s capture feature to pass data from TCP mode to HTTP mode prompted me to update my SSL configuration. This was intended to get an A+ rating from SSL Labs by sending non-SNI capable clients to a server with weaker ciphers. This was to enable clients on WinXP/IE8, Java 6,…
MX on a Dynamic IP Address
I often see posts asking about running a mail server on a Dynamic IP address. Twenty years ago I started running my server on a dynamic IP address. However, times have changed, and it is more difficult to do so. Stil, there are mail server roles that work reasonably well on a dynamic IP address.
Disabling SSLv3 to block Poodle
The new Poodle vulnerability lead me to disable SSLv3 on my Ubuntu server. I have TLS/SSL enabled on three services: apache2, exim4, and dovecot2. Each service required a different method to disable SSLv3. While SSLv3 is mostly history, the techniques I used can be applied to other TLS versions. Ubuntu uses configuration files split into…
Hostnames for eximstats Rejections
I use eximstats to report my daily email traffic. I have a fairly high rate of rejections and wanted hostnames listed in the rejection reports. To resolve this I developed a patch to capture the hostname related to the IP address, and add this data to the rejection reports. The enhanced list saves me the…
Email Logins for Dovecot and Exim
Configuring a common login for Dovecot IMAP(s) and Exim SMTP. Also Exim Submission port and TLS (SSL) configuration.
Implementing IPv6 Part 2
Replacing 6to4 tunnel with 6in4. IPv6 enabling Bind, Exim, SPF, Squid, and updating Databases containing IP addresses.
Blocking Spam with Exim
Spam blocking techniques for Exim. Uses delays to cause Spambots to fail. Notes on bulk and automated mail servers.