Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

I failed to get ftp://ftp.mozilla.org/pub/mozilla.org/js/rhino1_7R3.zip, so I did nslookup mozilla.org, which returns Non-existent domain. But it's OK when I visit https://developer.mozilla.org

Why is this happening?

I am in a LAN and the DNS is in the LAN.

share|improve this question
Any firewall/proxy in your LAN? –  arsane Feb 22 '12 at 8:55
@arsane proxy. But will the browser use proxy for name resolv? –  onemach Feb 22 '12 at 8:58
Yes, you can either use proxy for name solving or local dns. I'm not sure which is the default way. I think the previous is reasonable, since for http proxy, the browser just send the url to proxy and leave the proxy to resolve address. As for one ip may map more than one domain name, so it's not reasonable to send the ip address to the proxy. –  arsane Feb 22 '12 at 9:48

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.