====== Anti-Spam Features ======

Like every website that accepts user contributed content, wikis are a target of spammers. [[DokuWiki]] has a few built-in methods to avoid spam. Additional methods can be added via plugin.

===== Access Control (built-in)  =====

The simplest method to protect your wiki from spam is to let only trusted users to use it. Refer to the [[acl|Access Control Lists (ACL)]] feature on how to set that up.

Of course this is not a viable option for community driven wikis. Read on for the other options that helped to keep dokuwiki.org spam free for years without having to disable anonymous edits.

===== URL Blacklisting (built-in) =====

As an active method against known spammers their URLs can be blocked. When a spammer tries to post a known spam-URL, the save will be aborted. DokuWiki comes with a small blacklist of URLs we encountered here on dokuwiki.org, but you can easily add your own.

See [[blacklist]] for details how this works.

===== Delayed Indexing (built-in) =====

To discourage spammers, DokuWiki uses a feature called [[http://c2.com/cgi/wiki?DelayedIndexing|DelayedIndexing]]. It tells search engines to not index pages that were recently updated. On an active wiki, spam will be removed very quickly by community members. Once a page has not been edited for a while, you can assume the community approves of the pages content and thus is spam-free.

See [[config:indexdelay|indexdelay]] for how to configure the time after which a page is considered old enough to be indexed and how to turn of this feature.

===== Mass Revert (built-in) =====

Whenever a spammer succeeds in spamming a huge amount of pages, it becomes hard to remove all the spam manually again. DokuWiki comes with the [[plugin:revert|Revert Manager]] plugin which allows you to easily revert all pages back to a version where it did not contain spam.

===== CAPTCHA (plugin) =====

A very effective method to protect your wiki against automated spam attacks is the use of a CAPTCHA. The most recommended plugin is the [[plugin:captcha|CAPTCHA plugin]]. It has various levels of usability settings and its default is invisible to most human users while still very effective against bots.

Installing this plugin is highly recommended on public wikis!

===== Registration Protection (plugin) =====

Spam bots are known to automatically register on wikis which will create a huge amount of useless, fake users. If you allow people to self register, it is advisable to protect the registration against spam bots. The [[plugin:captcha|CAPTCHA plugin]] is able to do that. Another option is the [[plugin:preregister|preregister Plugin]] which adds an email confirmation to the registration process.

Of course you can also disable the registration completely using the [[config:disableactions]] option.

Hint: should your wiki have been hit by a registration bot in the past, you can easily delete users by removing them from the ''conf/users.auth.php'' file instead of manually deleting them via the [[plugin:usermanager|user manager]].

===== More Plugins =====

Check the plugin list for plugins tagged with [[plugintag>spam]] to find more plugins to protect your wiki.