25

A CNAME is a type of DNS record, where a hostname points at another hostname. An A record is another type of DNS record, where a hostname points at an IP address. A subdomain is what you described as 'the left side of the domain', e.g. webmasters.stackexchange.com is a subdomain of stackexchange.com. The DNS setup for a subdomain could use either an A ...


17

2007: Here what Google's Matt Cutts has to say about sub-domains vs folders: My personal preference on subdomains vs. subdirectories is that I usually prefer the convenience of subdirectories for most of my content. A subdomain can be useful to separate out content that is completely different. Google uses subdomains for distinct products such news.google....


16

It will remain fr.somewhere.com unless you have rewrite conditions configured correctly: RewriteCond %{HTTP_HOST} =fr.somewhere.com RewriteRule ^(.*)$ http://www.somewhere.com/$1 [R=permanent,L] I have a cname record created for blog.legoservices.com which just points to tumblr, but all you see is blog.legoservices.com.


14

You're right that the trick is a wildcard DNS entry (indicated with asterisk) . Essentially it's a DNS entry that will match all subdomains that don't have a specific DNS entry. Then the "routing" happens on the application/website side. There is no actual DNS entry created for the subdomain, the reason that it finds a "match" when a DNS request is made, is ...


14

Indeed you can. For instance some do not realize a www. url is an actual sub-domain. So it is happening all the time. You can go to your server settings and choose your sub-domain as the main domain name or add some code to create a redirect. Many people use Apache servers for hosting websites and when you have used a domain name with traffic to it, a ...


13

You can serve a different robots.txt file based on the subdomain through which the site has been accessed. One way of doing this on Apache is by internally rewriting the URL using mod_rewrite in .htaccess. Something like: RewriteEngine On RewriteCond %{HTTP_HOST} !^(www\.)?example\.com$ [NC] RewriteRule ^robots\.txt$ robots-disallow.txt [L] The above ...


11

Generally, you have to use a separate sitemap for each host (i.e., different protocol, domain, or subdomain): From the FAQ "Where do I place my Sitemap?": All URLs listed in the Sitemap must reside on the same host as the Sitemap. For instance, if the Sitemap is located at http://www.example.com/sitemap.xml, it can't include URLs from http://...


9

i just came across this info graphic from slingshot that might be of interest : (source: seomoz.org)


9

After receiving clarification on this from John Mueller at Google, disavowing a root domain will also disavow all other sub domains under it. For example, disavowing:- domain:example.com Will also disavow:- sub23.example.com sub4646.example.com www.example.com You can of course, disavow individual sub domains like domain:sub23.example.com though which ...


8

uk is a TLD (top level domain). uk is the ccTLD (country code TLD) for the United Kingdom. All uk domains are controlled by Nominet. Nominet imposes additional restrictions on the registration of these domains. No-one can register a subdomain directly under the TLD uk. They must register a domain under one of the defined subdomains .co.uk, .org.uk and one or ...


7

The subdomain is nothing else than a DNS record applied to the root domain. If you consider the root domain example.com, any of the following is a valid subdomain www.example.com foo.example.com foo.bar.example.com and even *.example.com *.foo.example.com Then way you create subdomains is creating a DNS record for them, regardless it's a single-level ...


7

Google's bots will still want to request /robots.txt from your sub domain and not /robots_static.txt which would have no meaning to them. RewriteCond %{HTTP_HOST} ^www\.static\..*$ [NC] RewriteRule ^/robots\.txt$ /robots_static.txt [L] When requests for /robots.txt are made from your www.static domain the /robots_static.txt file will be served up as if it ...


7

You most certainly do not have to buy store.xyz.com as a new domain name. store.xyz.com is a part of xyz.com A domain name is made up of multiple parts www.google.com www.google.com | | | --- domain name extension | | --- domain name | --- subdomain mail.google.com mail.google.com | | | --- domain name extension | | --- ...


7

As per Matt Cutts blog post, he said: A subdomain can be useful to separate out content that is completely different. Google uses subdomains for distinct products such news.google.com or maps.google.com, for example. This is similar to what Blogger (blogspot) does. John's blog (john.blogspot.com) is totally different from Doe's blog (doe.blogspot....


6

Google does use domain authority to rank sites, or at least they use the Panda update to demote pages on a site-wide basis. From Google's original announcement in 2011: This update is designed to reduce rankings for low-quality sites—sites which are low-value add for users, copy content from other websites or sites that are just not very useful. At the same ...


6

First of all, as you're mentioned the reason to change that are cookies - there's no need - see "sub-domain cookies, sent in a parent domain request" on Stackoverflow: The leading dot in the domain value .example.com means example.com and its sub-domains. Without the leading dot, the cookie is only valid for this specific domain. Note that when ...


6

Yes, this is definitely possible. But please note that, by convention, www.domain.com is just an alias for domain.com. So, what you describe is not at all standard and violates most users' expectations. It also runs at least some risk of search engine penalties. So, in my opinion, it is not a good idea, but yes, it's possible. Exactly how you do it depends ...


6

will browsers recognize individual files as being the same as pre-cached ones, if they are served from different subdomains? No. Two identical files served from different locations are different files as far as the browser (cache) is concerned. The URL is the key by which the file is cached by the browser. As media1, media2 etc all serve the same files, ...


6

You can remove the sub-domains in webmaster tools, but first you need to add the sub domains as seperate sites and then submit a site removal. They should be gone within a day or so. See these instructions for removing a site from google : https://support.google.com/webmasters/answer/1663427?hl=en


6

This is normal behavior. I am not sure what your question is exactly. But here goes. I am going to assume you are using Apache and host your DNS. Create the sub-domain on your server however you need. For Apache, this would be almost exactly like any other domains website. You can find the configuration files in /etc/apache2/sites-available or /etc/local/...


6

You display companies information on your site, you need to use one website as a companies directory, it's logical. Option 1 Using a subdomain for each company seems complicated to maintain in the future... Moreover for SEO, you don't give all the value to your website but a little value to many websites (subdomains are treated as different websites for ...


6

It's possible exactly the same way that unix.stackexchange.com itself is possible. DNS does not impose any specific hierarchy, like "subdomain – domain – toplevel", you can add as many labels as you need, and add delegations at any level. (Take "www.theregister.co.uk" for example. Is "theregister.co.uk" a domain or a subdomain? It's both.) In other words, ...


6

To start, I've never really found a hard and fast "best" answer here in terms of which setup will help you the most with Google. I've gone both routes and been able to get sites ranking in Google either way. You can be penalized for keyword stuffing (and other reasons) no matter what direction you go. Now, that said, in general, if you are looking at what ...


6

Yes, You can. you will have to add the NS records for the subdomain in the DNS Manager for your TLD (Top Level Domain). For Example: In DNS Manager for TLD add NS records Like. bla.example.com. 1799 IN NS ns1.subhosting.org. bla.example.com. 1799 IN NS ns3.subhosting.org. bla.example.com. 1799 IN NS ns2.subhosting.org.


5

You REALLY don't want to be using both the www subdomain AND the naked domain. This is terrible on the SEO. You can pick either, and it makes no difference which, but once you choose, you must stick with it. The reason you get that Facebook error is because you originally configured it to use the named domain, and it treats the www subdomain as a separate ...


5

If you want a real answer, talk to a lawyer. That said, your example isn't all that imaginary. cars.com already uses car brands in URLs, as directories. There's no obvious reason to think using them as sub-domains would be a special situation worth suing over versus directories. If anything, the trademark holders should sue for both just to be sure. ...


5

Technically, www is a subdomain of example.com. As with any subdomain, you can create a CNAME record to point it to another host. See this for more on CNAME's and an example of pointing www to another host: DNS Made Easy: Example 3 I'd strongly recommend against doing this however if it will take them to another site because it will really confuse ...


5

Setup both the domain and the subdomain in google webmastertools, and set your preferred version to be the subdomain one, then in the 'naked' domain (mydomainsite.com) if you are using apache, put this in the .htaccess (mydomainsite.com/.htaccess) RewriteEngine On RewriteCond %{HTTP_HOST} !^subdir\.mydomainsite\.com$ [NC] RewriteRule ^(.*)$ http://subdir\....


5

Google will automatically treat subdomains as part of the main site when: They have related content They are written by the same person or company They link to each other From Vanessa Fox, an ex-Google employee: Google is no longer treating subdomains (blog.widgets.com versus widgets.com) independently, instead attaching some association between them. ...


5

Yes. Whatever the web root for the subdomain is where you would put a robots.txt for that subdomain's contents. It will not affect the root domain and the root domain's robots.txt will not affect the subdomain.


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