DC3HAM Firewall Issue on 9th May 2023

Dear Customer,

A standard change on the internal Firewall in our DC3HAM colocation triggered a high availability problem because of a years old unnoticed configuration error. This error resulted in the intrusion prevention blocking hosts that should not have been blocked, including DNS. These cascading error unfortunately took a while to cleanup.

A complete review of the firewall rules is already underway by 2 people independently.

Best regards
Your MCON Managed Service Team