Manual:$wgNoFollowLinks/nl

Details
If true, external URL links in wiki text will be given the  attribute as a hint to search engines that they should not be followed for ranking purposes as they are user-supplied and thus subject to spamming. Defaults to true.

Zie ook

 * - the easiest way to manage whitelisting (since nofollow is not applied to interwiki links)
 * Manual:Costs and benefits of using nofollow
 * nofollow, Meta-Wiki discussion on nofollow's use on Wikimedia sites. Some of the arguments raised there may also applicable to other wikis' decisions concerning this configuration setting.
 * Manual:Costs and benefits of using nofollow
 * nofollow, Meta-Wiki discussion on nofollow's use on Wikimedia sites. Some of the arguments raised there may also applicable to other wikis' decisions concerning this configuration setting.