SPF and DKIM records are used to verify the authorised mail server allowed to send emails for that domain.
Enabling such records will help for better mail delivery and is recommended to be enabled on all accounts.
Adding Domain Keys for All Users
for user in `ls /var/cpanel/users`; do /usr/local/cpanel/bin/dkim_keys_install $user; done
Adding SPF Records for a All Users
for user in `ls /var/cpanel/users`; do /usr/local/cpanel/bin/spf_installer $user; done