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dancks

macrumors regular
Original poster
Nov 8, 2009
100
0
I first noticed it yesterday. It only happens at school. I'll just show the before after pics.

online:

Screen shot 2012-12-12 at 3.57.42 AM.png

offline:

Screen shot 2012-12-12 at 3.58.09 AM.png

From what I can tell thats the only thing that changes. Any ideas? Was I hacked by a pc????
 

rthpjm

macrumors 6502a
Jan 31, 2011
720
309
U.K.
DNS and DHCP

It's to do with the way your mac figures out what it's called when it starts up ( it may do this when it detects a network change too ).

What you're seeing is your hostname. Your Mac determines it's hostname from what you set in the Preferences : Sharing panel. This is what you see when you are not connected to anything (offline in your pictures), and you'll also see this if there is no DNS server running on the network.

Now when you connect to the school network, your school will have a DNS server. In this case your Mac will ask the DNS server for the name that is associated with your assigned IP address. In your case the DNS server returns the name 'Christopher-pc' and that's what your terminal prompt (and hostname) gets set to.

You have not been hacked. It's nothing to worry about.

Having the school DNS server actually reflect the correct name of your machine is a whole different discussion. You'd need to talk to your school IT team about DHCP/DNS dynamic name updates. The MacOS will do this but it can seem like smoke and mirrors, and I bet your school network is based on Microsoft products. I personally like Microsoft server's DNS and DHCP implementations, but I find Microsoft-focused IT techs can't get their heads around MacOSX. YMMV.

----------

Try putting your machine name in the System Preferences : Network : Advanced : DHCP Client ID field.

If you are lucky, your Mac will tell the school DHCP server its name, and then the school DHCP server will update the school DNS server. Magic :)
 
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