What I meant by CNAMEs

(This is an advanced technical topic)

Although Opera published → a way to setup domain for your Opera Unite (which is good, means they have no moral objections to using your own domain), it is far from what I meant. That will only work for people with external IP (all of us behind NAT still have no options - Opera Unite itself works, but no domain love).

Is it a common problem? Well, my city has a couple ISPs, two of them that I use both have 1 external IP for thousands (it might tens of thousands by now) of people each. So, no one in our city can use that. And since there's less and less IPv4's left every day it going to only get worse.

What I meant was the following: ...operaunite.com currently resolves unrecognized domains to main site, try wrong-wrong-wrong.operaunite.com →.

So if I make an CNAME entry:

mydomain.com CNAME mydevice.mylogin.operaunite.com

Then I make a query to mydomain.com, the request goes to IP of operaunite.com, with header:

Host: mydomain.com

OperaUnite's server sees if it can recognize it (it can't) and shows default homepage for Opera Unite.

But if (after getting the request) they'd do

nslookup -q=any mydomain.com

(in low-level commands, obviously), they would discover abovementioned CNAME entry, which then they could parse into "mydevice" and "mylogin" appropriately.

This means that even people behind routers/firewall/NATs could make use of domains.

/Although first Opera needs to sort out connectivity problems, those start to annoy me seriously (No server is available to serve your request)/

If you have external IP (even dynamic - check out the article →).

Slava V. [about me]

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