In the Domain Name System (DNS) hierarchy, a subdomain is a domain that is part of a larger domain.[1]

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Can subdomain.example.com set a cookie that can be read by example.com?

I simply cannot believe this is quite so hard to determine. Even having read the RFCs, it's not clear to me if a server at subdomain.example.com can set a cookie that can be read by example.com. ...
23
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2answers
2k views

Is there a maximum subdomain depth?

Is there a maximum allowed subdomain depth supported by webservers or browsers? For example, could a domain like foo.bar.baz.monkey.pirate.google.com cause problems?
21
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1answer
1k views

If I own a domain do I own all of its sub domains?

If I own a domain do I own all of its sub domains? For example if I purchase example.com, do I automatically own mail.example.com, blog.example.com, etc? If I do not own the sub domains, can anyone ...
17
votes
6answers
12k views

Wildcard SSL certificate for second-level subdomain

I'd like to know if any certificates support a double wildcard like *.*.example.com? I've just been on the phone with my current SSL provider (register.com) and the girl there said they don't offer ...
14
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2answers
975 views

Are DNS records private information?

Assuming you wanted to create a subdomain that points to a private location (perhaps the location of a database, or the IP address of a computer you don't want people to attempt SSH-ing into), so you ...
13
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2answers
831 views

Should engineering have its own DNS zone, delegate, or subdomain?

We have our organization's primary domain (with AD) example.com. In the past, previous admins have created several other zones - such as dmn.com, lab.example.com, dmn-geo.com etc - as well as ...
12
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4answers
13k views

How do I redirect subdomains to a different port on the same server?

I have some subdomains I want to redirect to specific ports on the same server. Say I have dev.mydomain.com I want dev.mydomain.com to redirect to mydomain.com:8080 how do I do this with Apache ...
11
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3answers
844 views

Can I use the character ñ in a sub-domain?

We are launching our website in Spanish and are probably going to call it espanol.mydomain.com Since the real spelling is español, ideally we would allow people to type español.mydomain.com. Is ...
10
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2answers
584 views

SSH home directory per subdomain

I'm wondering if it is possible to set different home directories for the same ssh user for each subdomain. So let's say you login with ssh myuser@example.com your home directory will be: ...
9
votes
3answers
6k views

Wildcard DNS and subdomains

Let'say that i've got the domain mydomain.com. I want that when any visitor goes to www.mydomain.com xyz.mydomain.com abc.mydomain.com asd.mydomain.com qwe.mydomain.com etc... the visitor will ...
8
votes
1answer
179 views

Create VHost & Forward subdomain to it

Gurus of So I have a simple .htaccess file where I only redirect non www to www for my webapp. Now what I want to do is Create a new vhost like http://subdomain.mydomain.tld Create a redirect for ...
8
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3answers
3k views

Second Level Subdomain DNS Wildcard

I need help setting up a second level subdomain. I have set up wildcard subdomains in the past with success, but I am having trouble with the DNS entry for this one. I need to do something like ...
7
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3answers
2k views

Is a wildcard DNS record bad practice?

I asked my hoster to add three subdomains all pointing to the IP of the A record. It seems he simply added a wildcard DNS record because any random subdomain resolves to my IP now. This is OK for me ...
6
votes
7answers
10k views

How do you have one IP address and many websites?

How can I have it where I have one IP address that sits on the Internet but many web names? For example, when a hosting company has a shared IP but I get unlimited domain names (along with everyone ...
6
votes
2answers
1k views

DNS: wildcard domains

If I have a wildcard domain, is it possible to list specific subdomains that override the wildcard one? For example: *.domain.com. 3600 IN A 1.2.3.4 foo.domain.com. 3600 IN A 9.9.9.9
6
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3answers
7k views

How to access a subdomain of an IP address?

I have a website that is accessible only by IP address. How can I access a subdomain of that website?
6
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5answers
597 views

Subdomains vs multiple domain names

I have the domain name for www.foo.co.uk. I am looking to use it as a landing page that will allow people to go to 1 of 2 sections of my site (both having separate blogs). So I have the idea I could ...
6
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3answers
3k views

subdomain of a subdomain?

I am trying to create url like sub2.sub1.subdomain.domain.com. I am planning to use this to display different content. my questions are... 1) Is it possible to create such multi level sub domains? - ...
6
votes
4answers
10k views

What Type of DNS Record do I Need to Make a Sub-domain?

I'm making a website, and I need a sub-domain. I need to email my host so he can add the sub-domain linking, but I don't know which type of DNS record to add on my end in the DNS. Is it A or CNAME? ...
6
votes
4answers
20k views

How to create a Subdomain in IIS7?

In IIS7 I have a site: http://www.mydomain.com/mysite How can I get the same site to appear as: http://mysite.mydomain.com ? I already have the DNS set up and can ping it, I just do not know how to ...
6
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2answers
6k views

How many sub-domains can there be at most?

Is there a limit for number of subdomains like "*.domain.com"?
5
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2answers
209 views

Validity of a FQDN with a hostname consisting entirely of numbers

Is a FQDN valid if the hostname component is entirely numeric? It's not something I've come across before and I'm not sure if something like the following is legal: 001.example.com. I know it's an ...
5
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2answers
3k views

Do I need child domains in AD?

I have a an organization having HQ(about 150 users) in one city and 16 branches (high schools, 300-400 users each) each in different city. What I have to do is create a domain(s) in AD for corporate ...
5
votes
2answers
9k views

How to create an SSL certificate for more than one subdomain?

I'm running a server "myserver.net", which has the subdomains "a.myserver.net" and "b.myserver.net". When creating (self-signed) SSL certificates, I have to create one for every subdomain, containing ...
5
votes
3answers
3k views

How to make a directory in site root a subdomain?

I have a Ubuntu LAMP site hosted at vps.net. I have a directory called john that is accessible via mysite.com/john I would like it instead to be accessed via john.mysite.com My site root is /var/www ...
5
votes
3answers
448 views

numeric subdomain

I have a question that I feel silly asking, but I can seem to find a definitive answer anywhere: Can I set up a subdomain that is purely numeric such as 2009.my.domain.com? Are there any ...
5
votes
1answer
897 views

Redirect all subdomains to subfolders

I'd like to add a rule so that all subdomains get redirected to a subfolder. For example: app1.example.com -> example.com/app1 app2.example.com -> example.com/app2 something.example.com -> ...
5
votes
3answers
539 views

Dns - wildcard vs. cname subdomains

Alright I have to admit I'm confused with how DNS works. I've always just added things until they worked, and now it's time to learn how they work. So one confusing thing to me is that there's sort ...
5
votes
1answer
2k views

Is this good practice for making subdomains

I'm trying to create subdomains with my web application, however, I'm not experienced in nginx that much, I've been trying to find a stable solution from SF, but unfortunately I can't find any good ...
5
votes
2answers
808 views

Hosting wildcard domains such as *.mydomain.com on Windows Azure without using redirections

I have an ASP.NET MVC app which offers wildcard domains to my users to personalize their login urls. I'd like to host this on Windows Azure. But is it possible to keep the wildcard domains? I've ...
4
votes
3answers
758 views

Can I use a single (non-wildcard) SSL cert on multiple hostnames of the same domain?

If I have test.example.com and prod.example.com (two hostnames, but same domain name) can I use the same SSL cert on both machines? In the past when I tried using a prod.example.com cert on ...
4
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3answers
326 views

Best practice for placing DNS records and subdomains

Say I have mydomain.com: Is it better to use option A: [A] mydomain.com 123.45.67.89 [A] www.mydomain.com 123.45.67.89 or option B: [A] mydomain.com 123.45.67.89 [CNAME] ...
4
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1answer
97 views

Why can the primary record for a domain not be a CNAME record? [duplicate]

I have read on the internet that the primary record for a domain (eg example.com) should be an A record, and that bad things happen if you use a CNAME record. I work for a web company that has ...
4
votes
1answer
464 views

Subdomain on another host (another IP, another provider)

Let's say my main domain is domain.net and i'm using it on a Media Temple (gs) server. I have my blog on the subdomain blog.domain.net Now I want to host my blog on my new VPS from Linode. So, I ...
4
votes
2answers
6k views

Wildcard vhosts on Nginx

I've just installed Nginx on my server and am extremely happy with the results, however I still cannot figure out how to insert wildcard virtual hosts. This is the [directory] structure I'd like: -- ...
4
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4answers
2k views

How to set up a DNS to use a catch-all address?

This is not really a programming question, it's more about settings that I can alter visually. I have bought a domain and am wondering how I can get it work in such a way that everything before the ...
4
votes
2answers
2k views

Why do we still use “www” in URLs? [duplicate]

Possible Duplicate: What’s the point in having “www” in a URL? Why do we prepend our URLs with "www", isn't http:// enough? Its clearly not necessarily because it is omissible. However ...
4
votes
3answers
2k views

nginx: redirect subfolder to subdomain

I'm trying to redirect a subfolder to a subdomain in nginx. I want http://example.com/~meow/ to be redirected to http://meow.example.com/. I tried the following: location ~ ^/\~meow/(.*)$ { ...
4
votes
2answers
3k views

How to configure IIS wildcards for account subdomains (like Basecamp)?

In effect I'm working on a SaaS application where I want to give subscribers their own subdomain to access their information (in code I will be pulling the first part of the subdomain for use as their ...
4
votes
1answer
30 views

Subdomain used as a param for main domain: CNAME vs A record

Let example.com be the main blog with a lot of articles about different topics. Now I want to have topic1.example.com to show only posts related to topic1. The Rails application that powers the blog ...
4
votes
2answers
316 views

Understanding the DNS domain lookup mechanism

The specific query that led me to try and unpick this process was: Will a DNS lookup for a subdomain, such as assets.example.com, be faster if the parent domain, example.com, has already been ...
4
votes
1answer
209 views

DKIM and SPF for a subdomain

I manage a VPS on Linode accessed through subdomain.example.com and I need to send email from this subdomain. I can't set any TXT records in Linode DNS manager because the name servers for example.com ...
3
votes
2answers
713 views

Can you have a sub sub domain?

Can you have DNS records with sub sub domains? E.g.: www.blog.domain_name.com? What about a sub sub wild card domain? At the same time supporting *.domain_name.com? E.g.: *.blog.domain_name.com?
3
votes
4answers
10k views

Redirect subdomain.example.org to somethingelse.com hidden to the user?

I'm not knowledgeable at all about C-NAMES, A-RECORDS, name servers and the like, so just bear with me on this one: I want to redirect subdomain.example.org to another domain somethingelse.com. I do ...
3
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1answer
124 views

Is there a way to check DNS records to determine the creation date of a subdomain? e.g. blog.example.com

I need to determine when a subdomain was created. Is there a way to do that with DNS lookups? For a given top level domain like example.com, can I find out when blog.example.com was created?
3
votes
2answers
156 views

Route www.<subdomain> to <subdomain>?

I have a domain that needs to redirect from www.subdomain.domain.net to subdomain.domain.net I know this is possible, but how? It isn't automatic. What DNS records do I need to update?
3
votes
2answers
3k views

How do I configure IIS 7 (discount asp.net) to point subdomains at application subdirectories?

I have an discount asp.net account, which uses IIS 7 and I want to configure subdomains to point at specific applications on the site. For instance: 's1.site.com' would run the application at ...
3
votes
2answers
2k views

Non-Wildcard SSL Certificate and Subdomains

I want to protect the login form of my blog application with an SSL certificate and I'd also like to have some subdomains set up for things like the Mint web stats package. Is this even possible using ...
3
votes
1answer
283 views

Common subdomain for several virtual domains in Apache2

I'm running a web server with Apache2 and several virtual domains. Also, there's a mail server for these domains, exposing a web interface. For each virtual domain example.com, I have the subdomain ...
3
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2answers
840 views

How to create this type of subdomain: example.test.domain.com

I've managed to find a rewrite for making subdomains (which I have a wildcard domain pointed to my server; *.domain.com. If I go to test.domain.com, it works just fine which transverse to: ...