When you have DirectAdmin installed on your Linux operating system (e.g. Ubuntu, CentOS), you should not update your operating system without taking care of one thing first.
DirectAdmin takes care of some packages itself, such as Apache or MySQL. So by updating these packages directly, you may cause some errors for DirectAdmin.
To only update packages that are not related to Direct Admin, you should exclude these. First, open yum.conf found in /etc/
sudo nano /etc/yum.conf
Then, paste the following code at the end of that file:
exclude=apache* httpd* mod_* mysql* MySQL* da_* *ftp* exim* sendmail* php* bind-chroot*
Now save the file (CTRL + X, Y, Enter) and perform an update without breaking Direct Admin!
sudo apt-get update
sudo yum update