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7 Improvements for Email Hosting on cPanel & WHM

cPanel & WHM Email Hosting Improvements

Email hosting on cPanel & WHM servers has improved greatly in the last year. Below are some awesome features we’ve recently added to make email hosting on a cPanel & WHM server a breeze for Web Hosting providers, system administrators and cPanel users.

1. SubAddressing (Release Note)

SubAddressing (also known as ‘plus addressing’) is the name for an email that uses a ‘+’ as part of the destination user. Subaddressing is a great way to filter emails out of your inbox without having to configure filters for each sender. This feature is useful for both system administrators, and for cPanel users!

For example, if I’m signing up for an account at a flower delivery service to send my dad a candy bouquet for Father’s Day, I can use the email address benny+flowerdeliveryservice@domain.tld to filter the inevitable barrage of future “offer” emails into a folder named ‘flowerdeliveryservice’ at my email account benny@domain.tld. This has the additional (and somewhat accidental) feature of allowing you to track who is sharing your email address with other companies as well, since each address acts as a unique address.

Side note: if you don’t create the folder before you use this address you do have to go to the server and manually subscribe to the new folder.

2. MDBox (Release Note)

MDBox is one of those features that is most appealing to system administrators, and that most end users will blow right past and never consider. Though the lack of an obvious or flashy name obfuscates its usefulness, the benefits of converting from Maildir to MDBox are huge and well worth a little reading.

Taking a step back: Maildir and MDBox are both storage formats used by the mail application on cPanel & WHM servers: Dovecot. There are lots of differences, but the one that pushed us to add support is that email stored with Maildir uses a simple 1-to-1 format, while MDBox uses a many-to-1 format. For the simple cPanel user it makes no difference at all, but for server administrator is can mean a whole lot. Allowing more than one mail message to be stored in a single file means lower inode use, which speeds up anything that requires disk access. Things like backups and account transfers for any cPanel with large email accounts take a fraction of the time, and can be done with minimal server impact.

If you’re curious about the details of the implementation, take a look at the release note from cPanel & WHM version 58.

Answers to some of the Converting-to-MDBox Frequently Asked Questions:

  • Mail operations do not go offline during conversion.
  • How long conversation takes will depend on the number of accounts and amount of email, but on a typical shared server it’s complete in well under an hour.
  • If you have a cron set up now that anticipates Maildir format, you’ll need to adjust it to use doveadm for its queries.

3. SNI Support in Dovecot (Release Note)

Elimination (or at least reduction) of domain-mismatch SSL errors was one of the things we wanted to accomplish as part of the introduction of AutoSSL last year. This would help prevent end-user confusion, and reduce support load for webhosts and system administrators. One of the ways we’ve done that is by adding SNI support for all services across cPanel, including Proxy Subdomains and common service subdomains. Adding SNI support to Dovecot means that emails users can set up a secure connection to their mail server using their own domain name, without encountering the mis-matched SSL Domain error that has plagued users and support teams for years.

4. Email Account Settings (Release Note)

One of the biggest frustrations we see from end-users comes when they want to check their email outside of the webmail interfaces on the server. As a webhosting provider, keeping your documentation updated for those users can be a huge resource drain. To start, there are a ton of different devices (phones, tablets, laptops, etc) that you and your support team have to be familiar with. When you add in the number of native applications (like Mail on MacOS and iOS) and third party applications (Thunderbird, Outlook, Mailbird, Claws, Opera Mail, etc.) to that, the potential combinations become dizzying.

Enter “Email Instructions

Send email account instructions

Using that little box inside the webmail interface a user can send herself instructions for configuring any cPanel-hosted email account. The real excitement starts when you notice that the email containing instructions also has a mobile configuration file attached to it. Open that mobile config file on your mobile device and 95% of the work is done for you already. All you have to do is confirm the settings and enter your password. The account is set up for you!

If you’re a pro user, then you can take this a step further: Add your WHM account login for your server to the cPanel app (for iOS and Android). Then you can login to webmail for any user on your server right from your mobile device, and send them the new account setup instructions with ease!

5. IMAP Full-Text Search Indexing (Release Note)

IMAP Full-Text Search Indexing (powered by Solr) is another one of those features whose benefit isn’t immediately obvious, even to system administrators. The plainly-stated way to explain this feature is that is provides incredibly fast searching for all of your email hosted on a cPanel & WHM server over an IMAP connection. As an email user you will immediately notice that searching your email is blazing fast, even if your email is hosted on the server. For someone who isn’t a huge fan of folders (anyone else using archive?) this is huge. It has had an actual, tangible, positive impact on my life, especially when checking email on my phone. It’s also true for all of these: any iOS device, Microsoft Outlook®, SquirrelMail, Horde, Roundcube, and Mozilla Thunderbird.

If you didn’t enable SOLR on the upgrade to version 64, you can enable it via the WHM’s Manage Plugins interface (Home >> cPanel >> Manage Plugins), or by running the install_dovecot_fts (full text search) script.

6. iOS Push Notifications (Release Note)

Getting email in a timely manner from your cPanel & WHM server on an iOS device can be frustrating. As an email user, you are forced to choose between a delay, or being forced to manually refreshing your inbox.  Though we added the best support possible for android devices in version 54, we didn’t add support for iOS push notifications until version 64. There’s a lot of manual work that goes into setting up iOS push on a server, due to how Apple requires things be configured. However, speaking from experience, the work is absolutely worth the peace of mind. If you’re interested, our documentation team put together a great walk-through for how to get iOS Push Notifications set up.

7. Mail Compression on Delivery (Release Note)

This feature will be most exciting to anyone (sysadmin or cPanel user) that is concerned about email taking up disk use in their cPanel accounts. Though it’s not quite out yet, I wanted to mention one more feature that should be in a production tier around the beginning of July. In version 66 we’re adding compression for emailed delivered to your server. It will be compressed as the email is delivered, whether you’re using Maildir, or MDBox, reducing the amount of space required by any email account on your server. Compression, when combined with MDBox, is making my email hosting blazing fast.

What’s next?

We always look out for improvements for our email hosting, but we want to hear form you!
What feature would you most like to see us improve in a future version of cPanel & WHM? Comment below!
This post composed to the soothing tones of the Tron: Legacy soundtrack. Header image credit.

benny Vasquez

scripter, crafter, cPanel's Manager of Community Engagement. Facilitating communication between cPanel's amazing development team, and cPanel's amazing community. Find me on twitter: @cpaneldev