More specific in msf console why when I 'nmap -v -A 192.168.1.8' I get all the results I expect (OS detection windows 8.1 etc), while when I do the same from armitage I get unknown? I have the same problem also when i 'db_nmap'.
My suggestion is to always be sure to have the latest development version of nmap (via Subversion) and to run it locally (I run it with the time(1) command under a script(1) typescript terminal session inside of the screen(1) terminal multiplexer), outputting to XML (or all formats).
Then, import the Nmap XML into Armitage or MSF. When doing so, are there still discrepencies? If so, you may want to open a bug with one or more of the three projects.
One factor I can think of is the way that nmap resolves the
-A flag. It is the equivalent of
-O -sVC. The flags
-v --version-all should be added to improve the scan results.
The most-likely answer here is that Armitage and MSF are using different nmap binaries. Using the Unix which(1) command or built-in or the
type -all bash built-in may allow you to uncover this sort of issue, but you may have to dig deeper into PATH environmental variables or in-framework settings that could call a different namp binary or load a different nmap-payloads file.