We have received the following details from Telia:
Last night we experienced couple of huge denial of service attacks between
2025-11-17 20:31:44 EET à 20:43:10 EET
and also
2025-11-17 23:07:44 EET à 23:15:10 EET.
Our defensing mechanism has probably been the reason for this outage. I will report this to our DDoS team. Sounds like a IP range whitelisting problem to me.
As a future guard against this problem, Telia have now explicitly allow-listed our outbound IP addresses.