Wikipedia suffers outage
{{date|February 13, 2006}}
{{WikimediaMention}}
[[Image:Logo collage.png|220px|right|thumb|Logos of various Wikimedia projects]]
[[w:Main_Page|Wikipedia]], the well-known free-to-edit encyclopedia, suffered a period of extended downtime starting approximately 10:00 UTC, following a failure of the primary [[w:Domain Name System|DNS]]/[[w:Network File System|NFS]] [[w:Server (computing)|server]], which caused numerous cascading failures on other servers within the [http://meta.wikimedia.org/wiki/Wikimedia_servers Wikimedia cluster].

This failure led to all [http://rr.wikimedia.org/ Wikimedia projects] and web sites being rendered inaccessible for several hours. Technical staff worked to restore services using backup equipment, and set up temporary hosts to fulfill some of the roles of ''[http://meta.wikimedia.org/wiki/Zwinger Zwinger]'', the failed host.

Following restoration of the backbone of the cluster, several problems arose within the database, causing pages to appear missing. At this time, it was noticed that the normal editing pattern of users was inadvertently causing damage to pages, although no histories were lost. The exact cause for the database issues is not known; while there was a heavy replication lag at the time, it has been asserted that this would not have caused such wide problems.

In order to prevent future problems and to protect the integrity of data, editing was shut off for two hours and 47 minutes. Meanwhile, technical staff worked to restore several [[w:Squid cache|squid cache]] servers and to reduce the dependencies on [[w:Network File System|NFS mounts]].

Editing returned to near-normal levels from about 21:45 UTC. 

As of 22:00 UTC, no official statement has been released commenting on the downtime.


<!--

Early rumours which spread round the internet, suggesting the cause of the crash to have been in connected to the posting of an article relating to the Danish "Muhammed Cartoons" issue, have been very quickly discounted though. 

-->
<!--
The cause of the outage, widely believed to be a technical issue with the servers used by Wikipedia (and other Wikimedia Foundation projects) is still under investigation, but the unofficial reason given by staff is that one of the servers that crucially handled the DNS went down and brought down several others as well.

Evidently, Wikipedia's primary internal DNS server (running on host "zwinger") failed, perhaps along with some other support and logistical services. By the time alternate DNS service was restored, other problems had manifested, including errors with the NFS mounts which are critical to Wikipedia's LVS architecture. Some of these problems threatened the integrity of the all-important database. For this reason the database was temporarily locked and editing disabled.
-->

==Sources==
{{original}}

{{publish}}
{{archived}}

[[Category:Internet]]
[[Category:Science and technology]]
[[Category:United States]]
[[Category:North America]]

[[es:Wikipedia y los proyectos de la Fundación Wikimedia presentan problemas en sus servidores durante el lunes]]
[[fr:Panne de Wikipedia du 13 février 2006]]
[[ru:Авария серверов Викимедиа]]
Logos of various Wikimedia projects
Wikipedia, the well-known free-to-edit encyclopedia, suffered a period of extended downtime starting approximately 10:00 UTC, following a failure of the primary DNS/NFS server, which caused numerous cascading failures on other servers within the  Wikimedia cluster.

This failure led to all  Wikimedia projects and web sites being rendered inaccessible for several hours. Technical staff worked to restore services using backup equipment, and set up temporary hosts to fulfill some of the roles of  Zwinger, the failed host.

Following restoration of the backbone of the cluster, several problems arose within the database, causing pages to appear missing. At this time, it was noticed that the normal editing pattern of users was inadvertently causing damage to pages, although no histories were lost. The exact cause for the database issues is not known; while there was a heavy replication lag at the time, it has been asserted that this would not have caused such wide problems.

In order to prevent future problems and to protect the integrity of data, editing was shut off for two hours and 47 minutes. Meanwhile, technical staff worked to restore several squid cache servers and to reduce the dependencies on NFS mounts.

Editing returned to near-normal levels from about 21:45 UTC. 

As of 22:00 UTC, no official statement has been released commenting on the downtime.
Internet Science and technology United States North America