Skip to content
    Moz logo Menu open Menu close
    • Products
      • Moz Pro
      • Moz Pro Home
      • Moz Local
      • Moz Local Home
      • STAT
      • Moz API
      • Moz API Home
      • Compare SEO Products
      • Moz Data
    • Free SEO Tools
      • Domain Analysis
      • Keyword Explorer
      • Link Explorer
      • Competitive Research
      • MozBar
      • More Free SEO Tools
    • Learn SEO
      • Beginner's Guide to SEO
      • SEO Learning Center
      • Moz Academy
      • MozCon
      • Webinars, Whitepapers, & Guides
    • Blog
    • Why Moz
      • Digital Marketers
      • Agency Solutions
      • Enterprise Solutions
      • Small Business Solutions
      • The Moz Story
      • New Releases
    • Log in
    • Log out
    • Products
      • Moz Pro

        Your all-in-one suite of SEO essentials.

      • Moz Local

        Raise your local SEO visibility with complete local SEO management.

      • STAT

        SERP tracking and analytics for enterprise SEO experts.

      • Moz API

        Power your SEO with our index of over 44 trillion links.

      • Compare SEO Products

        See which Moz SEO solution best meets your business needs.

      • Moz Data

        Power your SEO strategy & AI models with custom data solutions.

      Track AI Overviews in Keyword Research
      Moz Pro

      Track AI Overviews in Keyword Research

      Try it free!
    • Free SEO Tools
      • Domain Analysis

        Get top competitive SEO metrics like DA, top pages and more.

      • Keyword Explorer

        Find traffic-driving keywords with our 1.25 billion+ keyword index.

      • Link Explorer

        Explore over 40 trillion links for powerful backlink data.

      • Competitive Research

        Uncover valuable insights on your organic search competitors.

      • MozBar

        See top SEO metrics for free as you browse the web.

      • More Free SEO Tools

        Explore all the free SEO tools Moz has to offer.

      NEW Keyword Suggestions by Topic
      Moz Pro

      NEW Keyword Suggestions by Topic

      Learn more
    • Learn SEO
      • Beginner's Guide to SEO

        The #1 most popular introduction to SEO, trusted by millions.

      • SEO Learning Center

        Broaden your knowledge with SEO resources for all skill levels.

      • On-Demand Webinars

        Learn modern SEO best practices from industry experts.

      • How-To Guides

        Step-by-step guides to search success from the authority on SEO.

      • Moz Academy

        Upskill and get certified with on-demand courses & certifications.

      • MozCon

        Save on Early Bird tickets and join us in London or New York City

      Unlock flexible pricing & new endpoints
      Moz API

      Unlock flexible pricing & new endpoints

      Find your plan
    • Blog
    • Why Moz
      • Digital Marketers

        Simplify SEO tasks to save time and grow your traffic.

      • Small Business Solutions

        Uncover insights to make smarter marketing decisions in less time.

      • Agency Solutions

        Earn & keep valuable clients with unparalleled data & insights.

      • Enterprise Solutions

        Gain a competitive edge in the ever-changing world of search.

      • The Moz Story

        Moz was the first & remains the most trusted SEO company.

      • New Releases

        Get the scoop on the latest and greatest from Moz.

      Surface actionable competitive intel
      New Feature

      Surface actionable competitive intel

      Learn More
    • Log in
      • Moz Pro
      • Moz Local
      • Moz Local Dashboard
      • Moz API
      • Moz API Dashboard
      • Moz Academy
    • Avatar
      • Moz Home
      • Notifications
      • Account & Billing
      • Manage Users
      • Community Profile
      • My Q&A
      • My Videos
      • Log Out

    The Moz Q&A Forum

    • Forum
    • Questions
    • Users
    • Ask the Community

    Welcome to the Q&A Forum

    Browse the forum for helpful insights and fresh discussions about all things SEO.

    1. Home
    2. SEO Tactics
    3. Intermediate & Advanced SEO
    4. Block an entire subdomain with robots.txt?

    Moz Q&A is closed.

    After more than 13 years, and tens of thousands of questions, Moz Q&A closed on 12th December 2024. Whilst we’re not completely removing the content - many posts will still be possible to view - we have locked both new posts and new replies. More details here.

    Block an entire subdomain with robots.txt?

    Intermediate & Advanced SEO
    5
    16
    111721
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as question
    Log in to reply
    This topic has been deleted. Only users with question management privileges can see it.
    • kylesuss
      kylesuss last edited by

      Is it possible to block an entire subdomain with robots.txt?

      I write for a blog that has their root domain as well as a subdomain pointing to the exact same IP. Getting rid of the option is not an option so I'd like to explore other options to avoid duplicate content. Any ideas?

      1 Reply Last reply Reply Quote 12
      • kylesuss
        kylesuss @kylesuss last edited by

        Awesome! That did the trick -- thanks for your help. The site is no longer listed 🙂

        1 Reply Last reply Reply Quote 1
        • sprynewmedia
          sprynewmedia @kylesuss last edited by

          Fact is, the robots file alone will never work (the link has a good explanation why - short form: all it does is stop the bots from indexing again).

          Best to request removal then wait a few days.

          1 Reply Last reply Reply Quote 3
          • kylesuss
            kylesuss @kylesuss last edited by

            Yeah. As of yet, the site has not been de-indexed. We placed the conditional rule in htaccess and are getting different robots.txt files for the domain and subdomain -- so that works. But I've never done this before so I don't know how long it's supposed to take?

            I'll try to verify via Webmaster Tools to speed up the process. Thanks

            1 Reply Last reply Reply Quote 0
            • sprynewmedia
              sprynewmedia @kylesuss last edited by

              You should do a remove request in Google Webmaster Tools.  You have to first verify the sub-domain then request the removal.

              See this post on why the robots file alone won't work...

              http://www.seomoz.org/blog/robot-access-indexation-restriction-techniques-avoiding-conflicts

              1 Reply Last reply Reply Quote 1
              • kylesuss
                kylesuss @kylesuss last edited by

                Awesome. We used your second idea and so far it looks like it is working exactly how we want. Thanks for the idea.

                Will report back to confirm that the subdomain has been de-indexed.

                1 Reply Last reply Reply Quote 0
                • sprynewmedia
                  sprynewmedia @kylesuss last edited by

                  Option 1 could come with a small performance hit if you have a lot of txt files being used on the server.

                  There shouldn't be any negative side effects to option 2 if the rewrite is clean (IE not accidently a redirect) and the content of the two files are robots compliant.

                  Good luck

                  1 Reply Last reply Reply Quote 2
                  • kylesuss
                    kylesuss @sprynewmedia last edited by

                    Thanks for the suggestion. I'll definitely have to do a bit more research into this one to make sure that it doesn't have any negative side effects before implementation

                    sprynewmedia kylesuss 6 Replies Last reply Reply Quote 0
                    • kylesuss
                      kylesuss @john4math last edited by

                      We have a plugin right now that places canonical tags, but unfortunately, the canonical for the subdomain points to the subdomain. I'll look around to see if I can tweak the settings

                      1 Reply Last reply Reply Quote 0
                      • sprynewmedia
                        sprynewmedia last edited by

                        Sounds like (from other discussions) you may be stuck requiring a dynamic robot.txt file which detects what domain the bot is on and changes the content accordingly.  This means the server has to run all .txt file as (I presume) PHP.

                        Or, you could conditionally rewrite the /robot.txt URL to a new file according to sub-domain

                        RewriteEngine on
                        RewriteCond %{HTTP_HOST} ^subdomain.website.com$
                        RewriteRule ^robotx.txt$ robots-subdomain.txt

                        Then add:

                        User-agent: *
                        Disallow: /

                        to the robots-subdomain.txt file

                        (untested)

                        kylesuss 1 Reply Last reply Reply Quote 2
                        • john4math
                          john4math last edited by

                          Placing canonical tags isn't an option?  Detect that the page is being viewed through the subdomain, and if so, write the canonical tag on the page back to the root domain?

                          Or, just place a canonical tag on every page pointing back to the root domain (so the subdomain and root domain pages would both have them).  Apparently, it's ok to have a canonical tag on a page pointing to itself.  I haven't tried this, but if Matt Cutts says it's ok...

                          kylesuss 1 Reply Last reply Reply Quote 1
                          • kylesuss
                            kylesuss @AdoptionHelp last edited by

                            Hey Ryan,

                            I wasn't directly involved with the decision to create the subdomain, but I'm told that it is necessary to create in order to bypass certain elements that were affecting the root domain.

                            Nevertheless, it is a blog and the users now need to login to the subdomain in order to access the Wordpress backend to bypass those elements. Traffic for the site still goes to the root domain.

                            1 Reply Last reply Reply Quote 0
                            • AdoptionHelp
                              AdoptionHelp last edited by

                              They both point to the same location on the server? So there's not a different folder for the subdomain?

                              If that's the case then I suggest adding a rule to your htaccess file to 301 the subdomain back to the main domain in exactly the same way people redirect from non-www to www or vice-versa. However, you should ask why the server is configured to have a duplicate subdomain? You might just edit your apache settings to get rid of that subdomain (usually done through a cpanel interface).

                              Here is what your htaccess might look like:

                              <ifmodule mod_rewrite.c="">RewriteEngine on
                                # Redirect non-www to wwww
                                RewriteCond %{HTTP_HOST} !^www.mydomain.org [NC]
                                RewriteRule ^(.*)$ http://www.mydomain.org/$1 [R=301,L]</ifmodule>

                              kylesuss 1 Reply Last reply Reply Quote 2
                              • AndyKuiper
                                AndyKuiper last edited by

                                Not to me LOL 🙂 I think you'll need someone with a bit more expertise in this area than I to assist in this case. Kyle, I'm sorry I couldn't offer more assistance... but I don't want to tell you something if I'm not 100% sure. I suspect one of the many bright SEOmozer's will quickly come to the rescue on this one.

                                Andy 🙂

                                1 Reply Last reply Reply Quote 1
                                • kylesuss
                                  kylesuss @AndyKuiper last edited by

                                  Hey Andy,

                                  Herein lies the problem. Since the domain and subdomain point to the exact same place, they both utilize the same robots.txt file.

                                  Does that make sense?

                                  1 Reply Last reply Reply Quote 0
                                  • AndyKuiper
                                    AndyKuiper last edited by

                                    Hi Kyle 🙂 Yes, you can block an entire subdomain via robots.txt, however you'll need to create a robots.txt file and place it in the root of the subdomain, then add the code to direct the bots to stay away from the entire subdomain's content.

                                    User-agent: *
                                    Disallow: /

                                    hope this helps 🙂

                                    kylesuss 1 Reply Last reply Reply Quote 3
                                    • 1 / 1
                                    • First post
                                      Last post

                                    Got a burning SEO question?

                                    Subscribe to Moz Pro to gain full access to Q&A, answer questions, and ask your own.


                                    Start my free trial


                                    Browse Questions

                                    Explore more categories

                                    • Moz Tools

                                      Chat with the community about the Moz tools.

                                    • SEO Tactics

                                      Discuss the SEO process with fellow marketers

                                    • Community

                                      Discuss industry events, jobs, and news!

                                    • Digital Marketing

                                      Chat about tactics outside of SEO

                                    • Research & Trends

                                      Dive into research and trends in the search industry.

                                    • Support

                                      Connect on product support and feature requests.

                                    • See all categories

                                    Related Questions

                                    • binhlai

                                      If my website do not have a robot.txt file, does it hurt my website ranking?

                                      After a site audit, I find out that my website don't have a robot.txt. Does it hurt my website rankings? One more thing, when I type mywebsite.com/robot.txt, it automatically redirect to the homepage. Please help!

                                      Intermediate & Advanced SEO | | binhlai
                                      0
                                    • AdamThompson

                                      Why does Moz recommend subdomains for language-specific websites?

                                      In Moz's domain recommendations, they recommend subdirectories instead of subdomains (which agrees with my experience), but make an exception for language-specific websites: Since search engines keep different metrics for domains than they do subdomains, it is recommended that webmasters place link-worthy content like blogs in subfolders rather than subdomains. (i.e. www.example.com/blog/ rather than blog.example.com) The notable exceptions to this are language-specific websites. (i.e., en.example.com for the English version of the website). Why are language-specific websites excepted from this advice? Why are subdomains preferable for language-specific websites? Google's advice says subdirectories are fine for language-specific websites, and GSC allows geographic settings at the subdirectory level (which may or may not even be needed, since language-specific sites may not be geographic-specific), so I'm unsure why Moz would suggest using subdirectories in this case.

                                      Intermediate & Advanced SEO | | AdamThompson
                                      0
                                    • EvansHunt

                                      Wildcarding Robots.txt for Particular Word in URL

                                      Hey All, So I know that this isn't a standard robots.txt, I'm aware of how to block or wildcard certain folders but I'm wondering whether it's possible to block all URL's with a certain word in it? We have a client that was hacked a year ago and now they want us to help remove some of the pages that were being autogenerated with the word "viagra" in it. I saw this article and tried implementing it https://builtvisible.com/wildcards-in-robots-txt/ and it seems that I've been able to remove some of the URL's (although I can't confirm yet until I do a full pull of the SERPs on the domain). However, when I test certain URL's inside of WMT it still says that they are allowed which makes me think that it's not working fully or working at all. In this case these are the lines I've added to the robots.txt Disallow: /*&viagra Disallow: /*&Viagra I know I have the solution of individually requesting URL's to be removed from the index but I want to see if anybody has every had success with wildcarding URL's with a certain word in their robots.txt? The individual URL route could be very tedious. Thanks! Jon

                                      Intermediate & Advanced SEO | | EvansHunt
                                      0
                                    • ecerbone

                                      Blog On Subdomain - Do backlinks to the blog posts on Subdomain count as links for main site?

                                      I want to put blog on my site.  The IT department is asking that I use a subdomain (myblog.mysite.com) instead of a subfolder (mysite.com/myblog).  I am worried b/c it was my understanding that any links I get to my blog posts (if on subdomain) will not count toward the main site (search engines would view almost as other website).   The main purpose of this blog is to attract backlinks.  That is why I prefer the subfolder location for the Blog. Can anyone tell me if I am thinking about this right? Another solution I am being offered is to use a reverse proxy. Thoughts? Thank you for your time.

                                      Intermediate & Advanced SEO | | ecerbone
                                      0
                                    • fablau

                                      Robots.txt: how to exclude sub-directories correctly?

                                      Hello here, I am trying to figure out the correct way to tell SEs to crawls this: http://www.mysite.com/directory/ But not this: http://www.mysite.com/directory/sub-directory/ or this: http://www.mysite.com/directory/sub-directory2/sub-directory/... But with the fact I have thousands of sub-directories with almost infinite combinations, I can't put the following definitions in a manageable way: disallow: /directory/sub-directory/ disallow: /directory/sub-directory2/ disallow: /directory/sub-directory/sub-directory/ disallow: /directory/sub-directory2/subdirectory/ etc... I would end up having thousands of definitions to disallow all the possible sub-directory combinations. So, is the following way a correct, better and shorter way to define what I want above: allow: /directory/$ disallow: /directory/* Would the above work? Any thoughts are very welcome! Thank you in advance. Best, Fab.

                                      Intermediate & Advanced SEO | | fablau
                                      1
                                    • djlaidler

                                      How do I list the subdomains of a domain?

                                      Hi Mozers, I am trying to find what subdomains are currently active on a particular domain. Is there a way to get a list of this information? The only way I could think of doing it is to run a google search on; site:example.com -site:www.example.com The only issues with this approach is that a majority of the indexed pages exist on the non-www domain and I still have thousands of pages in the results (mainly from the non-www). Is there another way to do it in Google? OR is there a server admin online tool that will tell me this information? Cheers, Dan

                                      Intermediate & Advanced SEO | | djlaidler
                                      0
                                    • nicole.healthline

                                      Soft 404's from pages blocked by robots.txt -- cause for concern?

                                      We're seeing soft 404 errors appear in our google webmaster tools section on pages that are blocked by robots.txt (our search result pages). Should we be concerned? Is there anything we can do about this?

                                      Intermediate & Advanced SEO | | nicole.healthline
                                      4
                                    • ENSO

                                      Robots.txt is blocking Wordpress Pages from Googlebot?

                                      I have a robots.txt file on my server, which I did not develop, it was done by the web designer at the company before me. Then there is a word press plugin that generates a robots.txt file. How Do I unblock all the wordpress pages from googlebot?

                                      Intermediate & Advanced SEO | | ENSO
                                      0

                                    Get started with Moz Pro!

                                    Unlock the power of advanced SEO tools and data-driven insights.

                                    Start my free trial
                                    Products
                                    • Moz Pro
                                    • Moz Local
                                    • Moz API
                                    • Moz Data
                                    • STAT
                                    • Product Updates
                                    Moz Solutions
                                    • SMB Solutions
                                    • Agency Solutions
                                    • Enterprise Solutions
                                    • Digital Marketers
                                    Free SEO Tools
                                    • Domain Authority Checker
                                    • Link Explorer
                                    • Keyword Explorer
                                    • Competitive Research
                                    • Brand Authority Checker
                                    • Local Citation Checker
                                    • MozBar Extension
                                    • MozCast
                                    Resources
                                    • Blog
                                    • SEO Learning Center
                                    • Help Hub
                                    • Beginner's Guide to SEO
                                    • How-to Guides
                                    • Moz Academy
                                    • API Docs
                                    About Moz
                                    • About
                                    • Team
                                    • Careers
                                    • Contact
                                    Why Moz
                                    • Case Studies
                                    • Testimonials
                                    Get Involved
                                    • Become an Affiliate
                                    • MozCon
                                    • Webinars
                                    • Practical Marketer Series
                                    • MozPod
                                    Connect with us

                                    Contact the Help team

                                    Join our newsletter
                                    Moz logo
                                    © 2021 - 2025 SEOMoz, Inc., a Ziff Davis company. All rights reserved. Moz is a registered trademark of SEOMoz, Inc.
                                    • Accessibility
                                    • Terms of Use
                                    • Privacy

                                    Looks like your connection to Moz was lost, please wait while we try to reconnect.