I live mainly in a Windows world, but occasionally I have to got down and dirty with a Linux box.
One of my particular hates is the way Linux will use a DHCP address supplied by a Windows server, but won't register itself in the DNS, so I have to go and put a static entry into my DNS.
After MUCH hunting around, I finally managed to get it working... and it's actually a very simple problem to fix...
On your DHCP server, right click on the Scope and change the DNS tab page to match below. It seems that Linux machines don't send out a "register me in the DNS" message (which Windows machines do), and you need to make the below changes to force the DHCP server to always send new registrations to the DNS.
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