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La question
Le lecteur SuperUser JqueryLearner veut savoir comment connaître l'adresse IP d'un site Web:
If I want to know the IP address of a website, then one way is to ping the website. For example, if I want to know the IP address of google.com, then I can ping it via the command prompt.
Can anyone tell me how to get the correct IP address?
Alors, qu'est-ce que JqueryLearner doit faire pour trouver les bonnes adresses IP pour les sites Web?
La réponse
Les contributeurs du super-utilisateur, Paul et lesca, ont la solution pour nous. Premièrement, Paul:
Your starting assumption is that all websites can be accessed via their IP address directly. This is not the case.
In many cases (I’d venture most cases), the website that is presented at an IP address is dependent on the website name you are requesting. For example, if you request superuser.com, you will first resolve this to an IP address, then make a request to the IP address for a specific webpage. It looks like this:
This is why a single web server can host multiple websites using a single IP address. In the case of the Stack Exchange sites, any or all of them can be on each of their servers, and you’ll get the one you ask for. If you just put in an IP address, you won’t get any of them, because you are not telling the web server which of the many websites you are after. In these cases, it may have a “default” website defined, or just return an error.
If you are trying to work around an issue with your DNS provider, then one option you have is to modify your hosts file so that you are resolving addresses yourself, rather than have an external party do it for you.
So for example, if you edit:
Suivi de la réponse de lesca:
To get the IP address of a website, the best way is to use the nslookup command. For example:
One more lookup proves I am right:
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