I like tools like xprobe2. I don’t have any real reason to use them, but it’s fun to poke around and see what information is available.
xprobe2 supposedly polls a target server, and judging by its replies, makes an educated guess as to what operating system it’s using.
There are some other tools that do this too; supposedly nmap can handle this as one of the many things it has at its disposal. And I’m sure there are some other tools that start with N that can swing it. 😉
Some problems: xprobe2 (I see there was an “xprobe1” project too) is quite a few years out of date for what I can tell. The last timestamp I see in the sourceforge collection is 2005, and I don’t know if changes in the operating system landscape have been reflected in xprobe2’s little digital mind. I have my doubts.
That might be why it thinks Google’s servers are running on Mac OS X. I guess that’s not impossible, and it might be that Google is deliberately confounding efforts like xprobe2. I trust the results from kernel.org a little more, although I don’t know if the site would rely on a backdated kernel … what with the NSA’s sudden emergence as the bad guy of the decade.
xprobe2 is in the Debian repos as just “xprobe,” and works fine. The AUR version, on the other hand, is well beyond its expiration date and will build a 0Kb package if you don’t wrangle with the PKGBUILD file first.
On top of that, the home page is a bit convoluted, and I seem to occasionally get twisted around and hit misdirected pages.
I mention all these things to highlight that, while it’s fun and a vaguely useful tool, I don’t know if I trust the output, I can see that the project is very much out of date, and I have a feeling some sites might be feeding it misinformation. So … use at your own risk. 😉