How can someone register on a forum with an ip address beginning with 10(or 172, 192) when it is a private address not routed on the internet? I have had a couple on a vbulletin forum i moderate on.
Just ignore them. If you are concerned about this IP, then do a Whois lookup on their IP to see where they come from (some countries may start with 10. for any reason).
That's my point it's a private ip address so no country begins with 10. Why is Vbulletin recording it is my question, there must be an external ip address?
I think you're missing the point. It's a private ip address not released on the internet but somehow it gets logged by VB. I'm just inquisitive, no big deal. I'm a systems consultant so I understand ip addressing but this is a puzzler.
the 10 block of IP's is generally reserved for internal/private intranets. It could be a number of things that cause this IP to show up. Most likely that it could be the hosting company scanning the servers for whatever reason.
Log the entire IP address, and email your hosting company asking if they use the IP address for any reason. Even let them know that you aren't considered with what they're using it for, only IF they're using it.