An operational error caused DNSSEC signatures of the “restena.lu” and “lu-cix.lu” zones to progressively expire between 15.06.2025 and 22.06.2025. Consequently, services relying on those domain names might have gradually became unavailable to users behind validating DNS resolver, once the cache of those resolvers expired. This particularly affected Restena mail service on 22.06.2025 between 06:33 CEST and 18:50 CEST. At that time, both zones were properly re-signed and their DNSSEC signatures updated, solving the issue.

Other Restena services, the .LU registry infrastructure, the .LU zone and any other .LU domain name were not affected by this problem.