You may find that you are unable to access your server via SSH even though you are providing the correct credentials. The SSH log (/var/log/secure) will show errors such as the following:
reverse mapping checking getaddrinfo for client.example.com [10.0.0.1] failed
- POSSIBLE BREAK-IN ATTEMPT!
This is related to the use of the UseDNS option in the SSH configuration. The UseDNS option must be explicitly set to "no" for cPHulk to work correctly for SSH logins.
Add the following line with the contents "UseDNS no" to your server's SSH configuration and then restart the service:
echo "UseDNS no" >> /etc/ssh/sshd_config