Enhanced Mail System

cPanel/WHM 11.25 implements some major changes throughout our mailing system. We've adjusted the Exim configuration to allow a single process to listen on multiple ports, thereby reducing RAM and CPU usage. In addition to this, we've also improved quota lookup efficiency.

Improved Mail Servers

We've reduced Courier and Dovecot's authentication engine memory usage and startup time. Now, the amount of time it takes to log in and receive mail has been drastically reduced.

Updated Webmail

RoundCube webmail can now operate using the lightweight SQLite database engine. This gives each email account its own SQLite database, and assigns ownership of the RoundCube process to the cPanel account, for easier process accounting.

Version 11.25 also updates RoundCube, SquirrelMail, and Mailman to their most current versions.

Improved DNS Clustering

Our DNS clustering utility, DNSAdmin, now sends updates in batches with a single call, reducing the server's memory consumption during DNS synchronization. We've also added a feature that will automatically disable unresponsive cluster members, preventing outdated information from being sent to up-to-date servers when the unresponsive server come back online. Plus, we've simplified reconfiguring and restarting BIND into a single call, speeding up the process.

Web Server Improvements

In older versions of our software, certain tasks would require that Apache restart multiple times. With our new queueing feature, we've drastically reduced the number of times Apache will be restarted when you're working with WHM.

Version 11.25 also improves the overall speed with which new accounts are created, due to a faster httpd.conf generation process.

Additional Performance Improvements

We've made the cPanel log daemon (cpanellogd) more robust, preventing delays in log processing — and a resulting over-consumption of memory — due to missing dependencies.

We've also succeeded in reducing the system load during installations, minimizing cpdavd's total CPU usage, and optimizing the startup time on all cPanel binaries by up to 40%.

In addition to these advancements, we've improved our cPanel mobile theme to be more compatible with devices that only have minimal JavaScript support, and enhanced reliability for remote MySQL setups.

Speedier Account Transfers

Transferring your account to another server? You can now configure account transfers to skip the /homedir directory, if you'd prefer to copy that folder using another method (such as rsync). This can greatly speed up the transfer time, especially if your account contains a large amount of data.

Faster, Less Resource-Intensive Backups

cPanel/WHM 11.25 comes with a few big improvements to our backup system. Firstly, we've reduced the amount of disk input/output required for backups. In addition, we've ramped up internal caching, to improve the overall speed of the backup system.