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What is the "official" url I should use if I want to indicate just a resource that fails as soon as possible?

I don't want to use www.example.com since its an actual site that accepts and responds requests and I don't want something that takes forever and fails from a timeout (like typing using a random, private IP address can lead to).

I thought about writing an invalid address or just some random text but I figured it wouldn't look as nice and clear as "www.example.com" is.

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Hm, maybe an invalid scheme? –  Šime Vidas May 16 '12 at 17:33
How about –  Rocket Hazmat May 16 '12 at 17:34
Take a look at this question: stackoverflow.com/q/10456044 –  Rocket Hazmat May 16 '12 at 17:40
You could make a script that just immediately returns whatever error code you want. –  Rocket Hazmat May 16 '12 at 17:42
@Rocket: hmm, isnt good for me, since it is taking around 30s to finally timeout, but the idea of starting the address with 0 seems to work. –  hugomg May 16 '12 at 17:43

3 Answers 3

up vote 2 down vote accepted

If you want an invalid IP, trying using

The first octet of an IP cannot be 0, so to will be invalid.

For more info, see this question: what is a good invalid IP address to use for unit tests?

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http://tools.ietf.org/html/rfc5735: - This block is assigned as "TEST-NET-1" for use in documentation and example code. It is often used in conjunction with domain names example.com or example.net in vendor and protocol documentation. As described in [RFC5737], addresses within this block do not legitimately appear on the public Internet and can be used without any coordination with IANA or an Internet registry. See[RFC1166].

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Why do requests to take ~30 sec to timeout, but times out immediately? –  Rocket Hazmat May 16 '12 at 17:54
@Rocket: I have no idea. Could be the browser I am using, could be the proxy server, I really dont know. –  hugomg May 16 '12 at 17:55
@missingno: My guess is that it has to actually try to connect to whereas is an invalid IP, so it doesn't even try. –  Rocket Hazmat May 16 '12 at 17:55

if it's in a browser then about: is fairly useless - but it would be better if your service returned the correct HTTP status code - e.g. 200 = good, 404 = not found, etc.


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But that won't fail, will it? –  Šime Vidas May 16 '12 at 17:34
How do you mean fail? –  web_bod May 16 '12 at 17:38
it's not even http... –  Janus Troelsen May 16 '12 at 17:38
I guess, the OP wants a 4xx response.. –  Šime Vidas May 16 '12 at 17:40

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