14 DAY TRIAL // Last night all of the .se websites disappeared from the Internet for more than an hour in some cases and none of the websites using that particular top level domain were accessible during this period. The problem popped up at around 22:00 local time and was caused by a faulty script that was used to update the .se zone data to the DNS records. Because of how DNS works the problem has propagated to many DNS servers around the world and it may still be affecting some users.
A routine maintenance planned for the ccTLD .se caused all DNS lookups for websites using it to fail. Some reports indicate that an extra “.se” was added to the address or even that the domain names would be appended to themselves. The problem was immediately discovered but it had already propagated to other DNS servers as the data was cached by ISPs and web hosting companies. The problem was fixed at its source but external DNS servers had to be manually flushed in order to be resynced with the accurate data.
The large Swedish ISPs resolved the problem shortly after the incident but it may still be possible that small ISPs or those outside the country be affected. At worst it could linger on for a full 24 hours before all DNS servers automatically sync with the new upstream data. There are over 900,000 registered .se domain names and all were affecter by the error. The problem has been tracked down to a faulty script used in the update, which didn't append the terminating “.” to the DNS records in the .se zone. It looks like a minor mishap but it broke down every single web address using the .se ccTLD.
“In connection with a planned maintenance work on Monday 12th of October .SE (The Internet Infrastructure Foundation) sent out a corrupt zone file at 21.45 PM. The cause was an incorrect software update, which, despite of our testing procedures it was not detected. Thanks to well-functioning surveillance system .SE discovered the error immediately and a new file with the DNS data (zone file) was produced and distributed within one hour,” a notification sent out by The Internet Infrastructure Foundation after the incident read.