DNS4EU Public Service: Outage of Sofia resolver

Summary
On October 10 at 18:31 EEST, one of the DNS4EU Public resolvers in Sofia experienced an outage. The issue was detected immediately, mitigated at 18:43 and fixed at 19:09

Root Cause
A corrupted certificate was uploaded to the resolver, causing it to enter a continuous restart loop.

Impact
Users connected to the Sofia resolver experienced up to 12 minutes of connection outage before the resolver was removed from anycast routing to prevent further disruption.

Resolution
At 19:02 EEST, the correct certificate was uploaded. The resolver returned to a healthy state and was reintroduced into anycast routing.

Preventive Actions
To avoid similar incidents in the future, we will implement steps to enable automatic recovery of resolver health in the event of certificate-related issues.

We sincerely apologize for any inconvenience this incident may have caused.