Release:
Again another layer of testing, it is older code and has been run on more systems but it takes longer for updates to get to it. Recommended Selection
Stable:
Very old but the most stable version around, it has been tested the longest.
We recommend you set to manual updates, Release option. I prefer manual over automatic because I like to keep a better eye on what has been changed.
If you select manual and you want to perform the update simply scroll down WHM and go to Cpanel > Upgrade To Latest Version.
This will update Exim, scripts, themes, Perl and Cpanel if updates are available - it will only update to the Cpanel release type you selected previously.
Tweak Settings:
This is one of the most important sections of the configuration for your server. It's where you set settings that apply to all users on the server, like enabling certain stats programs.

Domains: Adding domains to the system.
[X] Allow Creation of Parked/Addon Domains that are [X] t registered
[yes] Allow Creation of Parked/Addon Domains that resolve to other servers (ie domain transfers) [This can be a major security problem. If you must have it enabled, be sure to [X] t allow users to park common internet domains.]
[X] Allow users to Park/Addon Domains on top of domains owned by other users. (probably a bad idea)
[yes] Prevent users from parking/adding on common internet domains. (ie hotmail.com, aol.com)
Mail: Email and related settings
[X] Add the mail. prefix for mailman urls (ie
http://mail.domain.com/mailman)
[yes] Attempt to prevent pop3 connection floods
[yes] BoxTrapper Spam Trap
[yes] Default catch-all/default address behavior for new accounts. fail will generally save the most CPU time.
Set to FAIL. This means that when someone sends to [X]
nexisting@company.com it will bounce
[yes] Email users when they have reached 80% of their bandwidth . Highly recommended
[yes] Horde Webmail - a webmail interface that has custom skins, [X] tes, filters and more.
[X] Include a list of Pop before SMTP senders in the X-PopBeforeSMTP header when relaying mail. (exim 4.34-30+ required)
[yes] Mailman Mailing list software, clients can use it through their own Cpanel.
[X] Neomail Webmail - Pretty crap webmail client with [X] features and [X] t any longer supported
Number of minutes between mail server queue runs (default is 60). I'd leave it at 60
[X] Prevent the user '[X] body' from sending out mail to remote addresses (php and cgi scripts generally run as [X] body if you are [X] t using phpsuexec and suexec respectively.) Do [X] T turn this on if you're [X] t using PHPSuexec, since you're reading this guide then leave this option UN[yes] ED or all contact form mail will BREAK!
[yes] Silently Discard all FormMail-clone requests with a bcc: header in the subject line - Helps cut down on mail queue build up.
[yes] SpamAssassin - Awesome spam filtering tool, highly recommended.
[yes] SpamAssassin Spam Box delivery for messages marked as spam (user configurable) - allows users to configure it through their control panel, very nice.
[X] SquirrelMail Webmail -A[X] ther webmail client, I don't like it personally.
The maximum each domain can send out per hour (0 is unlimited): If you have clients on your server I suggest entering a high value such as 500. This limits the sending amount of mail for the entire domain, [X] t per email address. If they start reporting they can't send messages out you can increase it.
The number of times users are allowed to [yes] their mail using pop3 per hour: 60 is recommended. That's 1 [yes] per minute which is high e[X] ugh.
[X] Track the origin of messages sent though the mail server by adding the X-Source headers (exim 4.34+ required)
MySQL: Database stuff
[yes] Use old style (4.0) passwords with mySQL 4.1 (required if you have problems with php apps authenticating) - [X] TE: Only use this if you have MySQL 4.1 installed.
[X] tifications:
[X] Disable Suspending accounts that exceed their bandwidth limit (will clear all suspensions is disabled) - Bad idea to turn this on. You WANT the account to get suspended so they're forced to upgrade and don't go crazy with bandwidth.
[yes] Disk Space Usage Warnings - Email users with their account starts running out of disk space.
[yes] Email Box Usage Warnings - Email users with their mailbox starts running out of disk space.
Software: - Extra server wide software available
[X] FormMail-clone cgi
Interchange Version to use (if you disable interchange, you must turn off the service in the service manager). I suggest disabling it, old and useless.
Loader to use for internal cPanel PHP (Use oldsourceguardian for version 1.x and 2.x). I suggest sourceguardian.
Stats Programs: - How you can view website traffic
[X] Analog Stats
[X] Awstats Reverse Dns Resolution
[yes] Awstats Stats - I like this, easy to use
[yes] Webalizer Stats - Has better file tracking, history features than Awstats
Stats and Logs: How the server handles log files
[yes] Allow users to update Awstats from cPanel - Lets them update stats manually, adds to server load.
[yes] Delete each domain's access logs after stats run
[X] Do [X] t include password in the raw log download link in cPanel (via ftp).
[X] Do [X] t reset /usr/local/apache/domlogs/ftpxferlog after it has been seperated into each domain name's ftp log
[yes] Exim Stats Daemon (required for smtp bandwidth logging; must also be modified in the service manager as well)
[X] Keep Stats Log (/usr/local/cpanel/logs/stats_log) between cpanel restarts (default is off)
[X] Keep log files at the end of the month (default is off as you can run out of disk space quickly)
Number of days between processing log files and bandwidth usage (default 1, decimal values are ok): 1
Stats Log Level (default is 1, larger numbers indicate more debug information in /usr/local/cpanel/logs/stats_log) [0...10]: 1
The load average above the number of cpus at which logs file processing should be suspended (default 0): 10 I suggest this value
[yes] When viewing bandwidth usage in WHM, always display in Megabytes first.
Stats and Logs: When you click on Server Status in WHM or Cpanel
The load average that will cause the server status to appear red (leave blank for default): 5 to 10 is recommended
System:
[yes] Allow Sharing Nameserver Ips - Allows you to give resellers private nameservers without dedicated IPs
[X] Allow cPanel users to install SSL Hosts if they have a dedicated ip. - Users usually screw this up, I suggest turning this feature off and installing it for them for a fee.
[X] Allow cPanel users to reset their password via email - Security issue, keep this off
[X] Allow cpanel and admin binaries to be run from other applications besides the cpanel server (cpsrvd).