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External links[edit]

The Scarcity link seems unnecessary. Hostnames are not scarce at all, since there are so many of them. Domain names might be scarce, but the article's not going to work with your current internet provider and the domain name is going to kick you off of your server for a dollar on

Host Name: www and host names like encarta[edit]

I don't get it what is this part of the domain name: http://[www] ? I think it may be like a server name for a particular company like http://[encarta] I have my own site so I'll write an example text like what appears in the url address the bold is what I see before "webhoster" ( webhoster is an example): http://[mysite] So why can't it be : http:// Anyone have an answer —Preceding unsigned comment added by Melab (talkcontribs) 00:13, 18 January 2008 (UTC)

The "www." before the domain name is (often) a name of a host, so you would have to change your DNS records (the A record, I think) to include a server named "www". So "www" does not mean anything special, and is not possible to just write "www." before. You have to name some computer "www". It is a common misthough (or mistake) to think that "www" is special in any kind other than it is often used as the left-most part of a Domain name for a web host. So dns:// would either point to the same site (configure youre DNS records to make www point to same IP address or redirect to dns:// There isn't always possible to write "www." at the beginning og the domain name, not even at the third stage (for example and point to different webpages). —Preceding unsigned comment added by SvartMan (talkcontribs) 17:54, 18 February 2009 (UTC)

Dash or Minus Sign or Hyphen?[edit]

In the article it says: "hostname labels can only be made up of the ASCII letters 'a' through 'z' (case-insensitive), the digits '0' through '9', and the hyphen". However, after looking up RFC 952, we learn that it is in fact a "minus sign", and after looking up hyphen we learn that they are not one of the same, and apparently it's not a dash either. So which is it? --Hm2k (talk) 20:57, 4 February 2008 (UTC)

I've answered this (duplicate) question on the Talk:Domain name page. Wrs1864 (talk) 21:32, 4 February 2008 (UTC)

What is a hostname versus what's not a hostname? (unclear wording)[edit]

The article provides an explanation for what is a hostname versus what isn't. The text reads,

The domain name "" is not a hostname since it does not have an IP address, but "" is a hostname. All hostnames are domain names, but not all domain names are hostnames.

Now, I pinged both example hostnames, and the first doesn't exist in DNS while the second does - but this wording is very unclear to people who might not understand how to check for themselves. As an example, it's very poor - I'm just uncertain as to how to reword it to make the most sense whilst still holding the same meaning as the current text. Anybody have any suggestions they can make to improve the clarity of the wording? Christopher (talk) 21:49, 23 March 2008 (UTC)

Yes, this section is definitely a bit unclear. I've added another subsection ("Determining hostnames on the Internet") to show how the existence of a hostname can be verified using the ping command. The quote you mention still needs to be improved however. WatchAndObserve (talk) 04:20, 9 July 2008 (UTC)

Is a hostname?[edit]

In the article it says, "both "" and "" are hostnames because they both have IP addresses assigned to them". However, I cannot get a response by pinging "". Is this a typo (perhaps "" is meant instead of "")? WatchAndObserve (talk) 04:01, 9 July 2008 (UTC)


Pinging is not a method to "verify" hostnames. If you want to find out if a domain name has an address you need to use DNS tools, such as dig, to resolve the name. In this case, both, and resolve to the same address. is a hostname, is the name of the domain (TLD) as well as a hostname, and both are also domain names, as they are both nodes in the tree of names(labels) in the DNS. Kbrose (talk) 04:43, 9 July 2008 (UTC)

Hi Kbrose, thanks for the clarification. However, the two hostnames in question above are the domain (with an "m") and not the more popular domain. WatchAndObserve (talk) 14:49, 9 July 2008 (UTC)


This article is indeed very confusing. The definition was never properly constructed based on clear concepts, And from there on it all just goes downhill. The article needs to discuss simple assignment of names to computers, and then how a host is inserted into the hierarchy of the domain name system. Kbrose (talk) 05:08, 9 July 2008 (UTC)

Resolving invalid hostnames / host names vs domain names[edit]

I've found that many non-Windows systems refuse to resolve host names with illegal characters such as for example '' or '', but if you force a link between host name and IP address with the /etc/hosts file or equivalent it resolves the address. As I understand it, for the domain name and host name issue, '' and '' have the same domain name ''. However, they are different host names, where 'host name' could refer to the names 'web' and 'ftp' which refer to hosts locally or '' and '' if referring to them from outside the domain (all host names since they all refer to a single host). Chadernook (talk) 18:15, 18 October 2008 (UTC)

find out a hostname[edit]

There may be a very simple and obvious way to do this, but, how would I find out the name of the host I'm trying to connect to (to use SSH) - (talk) 07:23, 23 October 2008 (UTC)

Wikipedia is not a help forum, but your question doesn't have enough information to answer the question. What do you know about the host currently? —fudoreaper (talk) 00:02, 25 October 2008 (UTC)

Article title: Hostname versus Host name[edit]

Based on a search of original documents, it looks like the correct spelling is two words (host name), not one (hostname). IEN 116, which appears to introduce the concept and name "host name" in 1979, spelled it with a space ( RFC 780, which defined the permitted length of a host name in 1981, spells it with a space. ( Newton's Telecom Dictionary likewise spells with a space. I realize there's inconsistency in usage worldwide (and within this article), but any objections to changing the article title to match the spelling used by the people who created the concept? Thirdbeach (talk) 22:24, 28 October 2008 (UTC)

Even the body that publishes the Internet standards is not consistent in this use and both are accepted in standards documents widely, for example, cf. RFC 1178, "Choosing a Name for Your Computer", uses the compounded form. As technological standards are revised we only accept as binding the latest published revisions, and not earlier ones. As this term probably also falls in this regime, it would have to be determined what the currently most accepted or proper form is, not the historical origin. Kbrose (talk) 22:44, 28 October 2008 (UTC)
I'm not sure I agree with a standard of "currently most accepted", partly because people who work with anything URL have an incentive to ram the words together; partly because, for example, we don't revise words like "nuclear" to "nucular" just because our current president mispronounces it; partly because the second law of thermodynamics has more opportunity to throw randomness into the spelling of an unusual phrase the longer the phrase exists. But for the sake of argument, a search on returns 954 results for hostname, and "about 6700" for host name. Search of returns 17 results for hostname, 362 for host name. Google returns 12.3 million for hostname, 42.9 million for host name. A search of the RFC archives returns 27 RFCs (2 numbered above 5000) that use hostname, and 43 (3 numbered above 5000) that use host name. Now, this smacks of WP:Original Research, doesn't it? Big no-no. Brings me back to my original suggestion: what's "proper" is most likely to be the name given by the originators. "Host name" is also the spelling in Newton's Telecom Dictionary, which is in its 24th edition of being the go-to resource for the language of telecom, networking, and the Internet. Absent a "published revision" that formally changed the spelling, I'd guess the most likely explanation is that the author of RFC 1178 was an engineer who either never noticed the original spelling or was comfortable with the way he spelled it in the command line, which would probably have been rammed together (the RFC was written in 1990, after all -- no UI). Thirdbeach (talk) 00:03, 29 October 2008 (UTC)
I'm not finding the same results as you are about the frequency. I find on 2,220 for "hostname" and 277 for "host name", on the larger internet, I find 12,400,000 for "hostname" and 4,450,000 for "host name". But, anyway, there have been similar debate about "e-mail" vs "email" and generally it has been considered a bad idea to rename stuff. Also see WP:ENGVAR as guidance. Wrs1864 (talk) 01:20, 29 October 2008 (UTC)
See how tempting it is to do original research? :-D My search used the search window: here and here. Note that both means also return results for host-name and host_name, which I'm not suggesting are correct but underscore the power of entropy. My reading of WP:ENGVAR is that its intent is to respect language variations, for example between British and American English. It was never intended to defend or preserve misspellings in Wikipedia, which is a better way to describe what's under consideration in this case. Thirdbeach (talk) 02:22, 29 October 2008 (UTC) Moved Thirdbeach (talk) 18:00, 29 October 2008 (UTC)
Just noticed that RFC 1178 refers to itself as an "essay" and states that "It does not specify any standard" -- it's explicitly not a binding standard. The actual standards are RFCs 1034 and 1035, which both use "host name". Apologies for throwing so much data around, but wanted to bring to the table the information you suggested is the basis for the ultimate decision. It appears pretty clear that the "currently most accepted", "proper", and "latest published technological standards" all support "Host name" as the more appropriate title. Do you come to the same conclusion? Thirdbeach (talk) 01:13, 29 October 2008 (UTC)

Hostname Restrictions[edit]

I edited hostname restrictions, because I don't think a hostname is allowed to begin with a digit. This is based on RFC952, but I'm wondering if there is a more up to date source for that. (I'm not entirely sure that DARPA host.txt rules still restrict modern DNS-based hostnames.) Davburns (talk) 19:26, 19 December 2008 (UTC)

This was changed a while back, in part to let register their domain name. See RFC 1123 section 2.1 Wrs1864 (talk) 19:33, 19 December 2008 (UTC)
Okay, I'd missed that. Thanks. Davburns (talk) 19:44, 19 December 2008 (UTC)

It still says a hostname cannot begin with a number and gives the RFC as source and a few sentences later it lists 3com as valid hostname. This is confusing. Ludwig Weinzierl (talk) 21:03, 12 November 2009 (UTC)p

Thanks. I edited the article accordingly. Kbrose (talk) 22:34, 12 November 2009 (UTC)

Hostname may (or not) be a domain name?[edit]

A hostname may be a domain name, if it is properly organized into the domain name system.

So this implies that the hostname is not always a domain name, even "if it is properly organized into the domain name system" (because of the wording 'may'). What I'm trying to understand is, are all the hostnames (resolvable over internet DNS infrastructure) are domain names? Unclear to me. If it is so, so the above paragraph should look something like this:

A hostname is a domain name, if it is properly organized into the domain name system.

But I'm not sure about this. Correct me if I'm wrong, or edit the main article. (talk) 18:54, 17 June 2009 (UTC)

I agree that the language 'may be' is a bit unclear. I think the intent of 'may be' in this sentence is something like 'is permitted to be', which is overly bureaucratic. So I agree with the suggestion to change the sentence as suggested by the anonymous user above. An alternate suggestion of mine is:

A hostname is a domain name when it is properly organized into the domain name system.

followed by

A domain name is also a hostname if it has been assigned to an Internet host and associated with the host's IP address.

The first suggestion would be ok. Kbrose (talk) 19:48, 17 June 2009 (UTC)

Is there a place where invalid hostnames can be reported? I am giving an example with a hostname which is dangerous which is what I work with all the time so you can see this is not just an academic question. The hostname is "-com DOT superhighest DOT ru". I have replaced the "." char with " DOT " for security reasons. I see no mention any place where to report the infraction of the RFCs or if somebody has teeth to enforce the rules. The days of polite people is long past. Also, in the orient they seem to have tossed all the rules out the door. If somebody can tell us WHERE we can report abuses, please put it in the main body and delete my remarks. Thanks. hhhobbit (talk) 01:00, 1 May 2010 (UTC)

This seems rather silly[edit]

It is possible for a single host computer to have several hostnames; but generally the operating system of the host prefers to have one hostname that the host uses for itself.

umm... What does that even mean? It "prefers it?" —Preceding unsigned comment added by (talk) 14:34, 31 March 2010 (UTC)

It usually means things might break if you find a way to ignore this preference. (talk) 10:28, 28 January 2011 (UTC)

Missing FQHN[edit]

Where and what is the “fully qualified host name”? -- (talk) 07:09, 28 September 2010 (UTC)


Re: " is a fully-qualified" -- even without the trailing period? (talk) 17:06, 9 March 2011 (UTC)

Yes, the period is not required in general. Only some software systems, e.g. DNS configuration files, require them. Kbrose (talk) 18:59, 9 March 2011 (UTC)

Hostname, Host Name or Host-Name[edit]

I've read the main page and the whole of this discussion several times over several days. There is a lot of confusion over the definition of "hostname" and "host name" and I've even seen someone asking about the use of "host-name". I've done a lot research this past week for the purpose of writing an article that will require me to define the difference between hostname and host name, if there is one. That research took me across Wikipedia (Hosts, Domain Name and Domain Name System, to mention a few) and several other sites in search of a definitive answer. Different Wikipedia articles seem to give different answers on their main pages and in their discussions; and most of the non Wikipedia sites seem just as confused.

I've read that "hostname" and "host name" have two very distinct meanings: hostname is supposed to refer to a domain name that has an IP address associated with it whereas "host name" is supposed to refer to the left most domain label of the hostname. For example, if had the IP address then it would be both a domain name and a hostname; and the domain "test" of would be the host name (i.e the name of the host for the services reached by dialling its particular hostname).

To add to the confusion, I've even seen what I've just defined as a "host name" referred to as a "local host name" or "local part" as opposed to just "host name", where "host name" is intended to mean what I've just described as a "hostname".

One place that offers the first definition is whatsmyipaddress; three places that offer the second definition are, bleepingcomputer and; and two places that lend weight to the first definition are and

Comparing "host name" with "local host name" does seem to lend credence to the idea that "host name" is a shorthand version of "local host name".

For my blog article I will stick with "hostname" to refer to a domain name that is mapped to an IP address and I will use "local part" or "local host name" to refer to the host device specified at the hostname's domain name's left most part (i.e it's final subdomain).

Can anyone offer a definitive solution to the question of whether there is any actual difference between "hostname" and "host name" or have the two terms become interchangeable since they were first used? Is there an alternative naming system for the separate parts of a domain name/hostname? And can someone with in depth knowledge of the subject please update this article and the other Wikipedia articles that I've mentioned above to make it absolutely clear as to whether there is a difference between hostname and host name? Diondeville (talk) 21:24, 24 July 2011 (UTC)

Validity of underscore (_)[edit]

Regardless of what is in the standards, the underscore is creeping into domain names. Just looking through some logs I found these three which all resolve (via dig) to valid ips.

This page ( suggests "RFC 2181 significantly liberalized the valid character set including the use of "_" (underscore) essentially saying that anything goes and its up to the client to validate in context."

The sentence "some applications (e.g. IE) won't work correctly if any part of the hostname will contain an underscore character[3]." is incorrect. IE9 appears to work fine and nothing in the reference suggests otherwise. I suggest that the use of _ is creeping in and support is mixed. In my opinion in order to be robust infrastucture should support it, but users should never rely on it working. Michaeldunn123 (talk) 17:30, 5 July 2012 (UTC)

Valid characters[edit]

The section regarding valid host names asserts that only a-z, 0-9, and hypen are allowed in host names. Meanwhile the Internationalized domain name article says that non-latin characters are allowed. This confusing contradiction should be clarified. Gilly3 (talk) 20:46, 13 December 2012 (UTC)

Virtual hosts and Subdomains are not mentioned[edit]

The article doesn't mention Virtual Hosts, even though that is a major aspect of the functioning of hostnames.

If my website is, I can create a special kind of hostname such as The article doesn't describe how such a name is implemented in the server (such as Apache) and in its configuration file (such as conf) and management tools (such as WHM and CPanel and the DNS system). It doesn't really explain how a virtual host differs from a regular host, even though it seems to listen on the same port. Such a description must also explain why a virtual host such as is useful, and is different from a subdirectory (like

There should at least be a link to Virtual hosting. We need an expert to expand this article to make it more complete and useful.

Oh, and Subdomain is just as relevant as virtual hosting. The article should explain how subdomains and virtual hosts differ, if they do. David Spector (talk) 01:14, 25 February 2016 (UTC)