Tuesday, January 11, 2011

Random DNS requests from chrome / chromium

Was looking at the sniffer trace today and noticed that chromium on startup queries some seemingly random-looking names. Especially did not make a whole lot of sense that they are within the local domain.

Turns out that this is this is Chrome dealing with the ISPs who show ads for nonexistent domain names - if you do a single-word query, then Chrome looks it up in DNS, in the assumption that you were trying to reach your local server, and if the resolution succeeds, then it offers you "Did you mean ...?" popup at the top.

Obviously, if the ISP is hijacking the NXDomain, you will get "Did you mean ?" for *every* single-word query, which would be disappointing - so in case Chrome can make the requests to those "random names" (and I've verified that by installing a local wildcard DNS server + a web server on the box) - then it stops both the strange-looking DNS requests and the "did you mean ...?" popup.

EDIT: looks like I was too fast to judge that the "did you mean ...?" popup disappears - after some use, in fact it does not. OTOH, maybe there is some additional cleverness involved in Chrome's behavior - because I merely return the default lighttpd page to it.

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