We have one requirement where we need to add robots.txt file into AEM to exclude our site from google search engine.. We have added the file on author and its working there but not working for publish instance.I have taken same package from author and import to publish instance but on publish we are getting 404 while trying to hit robots.txt directly through URL. Any help will be appreciated. Thanks in advance.
In addition to what Arun mentioned, If you are getting 404 for the robot.txt file when directly accessing it via publisher(Bypassing dispatcher), make sure the anonymous user has access to the location of robot.txt file.
Where that file is hosted? If it is under /content/you-project then try clearing your domain cache or if it is hosted under any specific restricted path then check the anonymous access.