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Always use the following permalink when referencing this page. It will remain unchanged in future help versions.

https://docs.sophos.com/nsg/sophos-firewall/19.5/Help/en-us/webhelp/onlinehelp/index.html?contextId=web-content-filters

Content filters

A content filter is a named list of terms. You can use content filters in policies to restrict access to websites that contain any of the terms listed. The default set of filters includes terms that are blocked by many organizations.

  • To create a filter, click Add content filter, type a name, and select a plain text (.txt) file.

For the text file, observe the following requirements:

  • Write each term on a separate line. The firewall evaluates the file on a line-by-line basis. For a match to occur, the line must be an exact match.
  • Metadata, comments, and column formatting are not supported.
  • Word lists containing characters outside of the ASCII character set must be saved using UTF-8 encoding.
  • Maximum file length is 2000 lines.
  • Maximum line length is 80 characters, including spaces and punctuation.

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