Dns

The central DNS servers for ru.nl for external requests had problems, because they received too many requests, which resulted in science.ru.nl and others not being found. DNS names within ru.nl then will not resolve to an IP address. We enlarged some TTLs (Time-To+lives) to try to lessen the problem. These small TTLs were meant to be able to move a service to a new server in case of problems, but now they just make the problem bigger. After starting VPN you won’t notice this problem, because the internal DNS servers that you use then are not affected. Changes to the RU DNS servers hopefully lessened or removed the problems as of 2021-02-23 14:30.

DNS-servers for ru.nl did not serve information about subdomains such as science.ru.nl. Thus no DNS-name will resolve to an IP address at FNWI. A workaround is to use as DNS servers: 131.174.224.4 en 8.8.8.8. If you try to connect to a service for the first time after ca 11:15, you’ll get an error like: “No such domain” or “Cannot resolve”. Restarting RU DNS servers at 12:45 may have fixed the problem. Without a real explanation, the problem went away after a few hours.