{"id":2228,"date":"2014-03-10T08:54:39","date_gmt":"2014-03-10T12:54:39","guid":{"rendered":"http:\/\/antipaucity.com\/?p=2228"},"modified":"2014-03-10T08:54:39","modified_gmt":"2014-03-10T12:54:39","slug":"a-smartish-dhcpd","status":"publish","type":"post","link":"https:\/\/merikebi.warrenmyers.com\/?p=2228","title":{"rendered":"a smart[ish] dhcpd"},"content":{"rendered":"

After running into some wacky networking issues at a recent customer engagement, I had a brainstorm about a smart[ish] DHCPd server that could work in conjunction with DNS and static IP assignment to more intelligently fill subnet space.<\/p>\n

Here’s the scenario we had:<\/p>\n

Lab network space is fairly-heavily populated with static assigned addresses – in a \/23 network, ie ~500 available address on the subnet, about 420 addresses were in use.<\/p>\n

Not all statically-assigned IPs were registered in DNS.<\/p>\n

The in-use addresses were did not leave much contiguous, unused space (little groups of 2 or4 addresses open – not ~80, or even a couple small batches of 20-30 in a row).<\/p>\n

DNS was running on a {{Windows 2012}} host.<\/p>\n

DHCPd (ISC’s<\/a>) was setup on an {{RHEL}} 5×64 {{Linux}} machine.<\/p><\/blockquote>\n

The problem with using the ISC DHCPd server, as supplied by HPSA<\/a>, is that while you can configure multiple\u00a0subnets<\/em> to hand-out addresses on, you cannot configure multiple\u00a0ranges<\/em>\u00a0on a single {{subnet}}. So we were unable to effectively utilize all the little gaps in assigned addresses.<\/p>\n

Maybe this is something {{DNS}}\/{{DHCP}} can do from a Windows DC, but I have an idea for how DHCPd could work a little smarter:<\/p>\n