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

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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 ...
33
votes
5answers
48k 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 transparently redirect to mydomain.com:8080 and I want to ...
29
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3answers
4k 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?
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4answers
48k 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?
26
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3answers
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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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1answer
2k 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 ...
15
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7answers
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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 ...
14
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2answers
1k 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 ...
13
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2answers
1k 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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3answers
2k 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 ...
12
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4answers
13k 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? - ...
12
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3answers
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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 ...
12
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6answers
11k 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 ...
11
votes
2answers
1k 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: /www/...
11
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3answers
13k 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?
11
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3answers
8k 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 ...
10
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2answers
20k 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: -- ...
9
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4answers
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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 ...
8
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1answer
196 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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2answers
3k views

How can I determine whether xyz.example.com uses a wildcard A record?

If you have many sub-domain names like xxx.example.com, xyz.example.com etc, you can solve these through server-side scripting or other means by using a wildcard A record for *.example.com in your DNS....
8
votes
3answers
6k 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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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
7
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1answer
358 views

DNS security & .com AD Domains, What are the dangers to my AD Domain if someone squats my public .com domain

I am aware that best practices currently dictate that my Windows AD Domain name should be a subdomain of a purchased, globally unique namespace (ie ad.namespace.com). That's just fine and dandy. My ...
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2answers
13k views

How many sub-domains can there be at most?

Is there a limit for number of subdomains like "*.domain.com"?
6
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3answers
1k views

Do I have to buy a second wildcard certificate for a subdomain?

We already have a wildcard certificate for *.mycompany.com. Our network has hosts that are only reachable internally. All of them belong to the internal.mycompany.com subdomain. There is a private ...
6
votes
5answers
616 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
votes
4answers
5k 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 ...
6
votes
2answers
520 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 ...
6
votes
1answer
6k 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 ...
6
votes
1answer
1k views

gitlab slow when running on nginx subdomain

I'm trying to run gitlab on a subdomain. I installed the latest gitlab version using the omnibus installer on my vserver (running Ubuntu 14.04.1) and disabled the bundled nginx and configured the ...
5
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3answers
1k 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] www....
5
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4answers
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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 ...
5
votes
3answers
1k 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
2answers
8k 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
1answer
2k 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
1answer
2k views

Can DNS host records be setup to create wildcard sub-subdomains

Is it possible to create a wildcard host record for a sub-subdomain ie *.foo.example.com?
5
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4answers
4k 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 ....
5
votes
3answers
8k views

Does each subdomain need it's own SSL certificate?

I am creating a websocket server which will live on ws.mysite.com. I want the web socket server to be SSL encrypted as well as domain.com to be SSL encrypted. Do I need to purchase a new certificate ...
5
votes
2answers
4k 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 ...
5
votes
1answer
1k views

Proxy HTTP requests to servers on different ports, using subdomain

Say I have a minimalist Python web server running with several instances, each with different ports specified as command line arguments. I'd like requests to my server to be redirected like this, ...
5
votes
2answers
2k views

Benefits of using a subdomain for sending email?

Assume I own the domain name, example.org. I am creating a setup where I receive email sent to me@example.org using Google Apps. The MX records for example.org already point to Google's servers and it ...
5
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4answers
3k views

Dynamic subdomain routing

I asked this question over at stackoverflow, but got very few views: http://stackoverflow.com/questions/2284917/route-web-requests-to-different-servers-based-on-subdomain Perhaps it's more applicable ...
5
votes
1answer
3k 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
978 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
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3answers
2k 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 test....
4
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3answers
666 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 ...
4
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4answers
339 views

Is a wildcard SSL required for a single subdomain?

A typical SSL cert is based on a common name for the domain (domain.com) sometimes (www.domain.com) as well. I understand what a wildcard cert is used for (*.domain.com) and it would/should validate ...
4
votes
1answer
189 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
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2answers
1k views

Setting up sub-domains with 123-reg.co.uk

Firstly I'm not sure if this was the right site to post this question, but it seemed more appropriate that using stack-overflow because its Web/DNS based. I'm having a bit of trouble setting up a ...
4
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2answers
4k 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 there ...