DNS Error Causes Sweden To Go Offline

An incorrect software update caused more than 1 million Websites in Sweden to go offline for more than an hour Monday night.

According to a news report, programmers forgot to add a crucial period when configuring a script upgrade, breaking the DNS lookup chain and leaving all of Sweden's domains off the grid until the problem could be located and fixed.

The Swedish Internet Infrastructure Foundation issued the following statement:

".SE (The Internet Infrastructure Foundation) sent out an incorrect zone file Monday October 12 at 21.45, in connection with a planned maintenance work. The cause was an incorrect software update, which, despite our testing procedures were 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.

"To minimize the impact on the availability of .se domains, we chose to produce and distribute a zone file that lacked proper signatures for DNSSEC to quickly come out with the correct DNS information. Subsequently, we generated immediately initiated a zone file according to normal procedures. It was fully distributed 01:00 am.

"The false information that was sent out affected accessibility to all .se domains for a short time. However, there may still be some name servers that have not changed out of misinformation against the real. BIND resolver can be forced to refresh the .SE-zone by issuing the command "rndc flush" or by doing a restart. Similar commands exist for other resolver softwares.

"Right now is an ongoing internal investigation to find out the cause of the faulty software update so that we can improve our procedures further."

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