How to pick the fastest cPanel update server.

While cPanel’s update system is quite robust and designed to be quick, sometimes you want to statically define which update server cPanel is using for its updates. You can do that quickly and easily.

You should be able to see which update server your server is already using by running this command on your server:

[~]# grep Using mirror /var/cpanel/updatelogs/last

If you want to test connection speeds to all of cPanel’s update (aka fast update servers) mirrors you should be able to do that with a command to test response time on port 80 using a command like this:

[~]# for x in `host httpupdate.cpanel.net | awk '{print $4}'` ; do nmap $x -p 80 --max-rtt-timeout 50ms ; done

Once you have picked a source or two that respond very quickly to your connection test, you can test the download speeds by downloading the latest cPanel release tarball from each server. For example, using the mirror 209.188.92.54 your command would look like this:

[~]# wget http://209.188.92.54/cpanelsync/RELEASE/Cpanel.tar.bz2

The final step would be to define which server or servers you would like to use. You can do that using a command like this:

[~]# echo HTTPUPDATE=209.188.92.54 >> /etc/cpsources.conf

Then you’re done! If you ever have problems updating in the future, and your cPanel update log shows connection errors, reverting this change should be your first step in troubleshooting.