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<p class=MsoNormal>Hello everyone,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I’m having trouble with our DHCP Server infrastructure.
A decommissioned DHCP server is still receiving a bunch of requests and we’ve
had IP conflicts as the result of having separate DHCP servers running for a
while.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Here is what happened…<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>We moved from a single DHCP server setup to a new failover
scenario, running v3.0.3. The initial migration worked well, we brought
down the old server, moved the appropriate files and then changed IPs and
brought the new guy up. At this point everything is great. Next, and
here is the beginning of the mistake, we tested the failover with the old DHCP
server which was moved on a different IP. At this point, the servers
probably balanced the load so both were working. We never advertised the
new IP on the old server as a helper, but plenty of people were served by
it. Once we believed we knew how to configure backup, we setup the new
backup server and configured the two new servers to work between each
other. So at this point now we have the primary/backup pair working and
the old DHCP server (in failover mode broken from the primary) is still serving
leases, waiting for the primary to come back online with it – which will
never happen.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Now, I’ve tried to get clients to move to the proper
pair with two separate actions, both with mixed success. First, I
configured that server to NAK all requests by changing the pools to ‘deny
known clients’ and ‘deny unknown clients’. This caused
about half the users to move to correct servers. The next action I took
was to shut off the DHCP service, this was over a week ago and I’m still
getting thousands of requests to the box – verified using tcpdump.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>My question is, is there a way that I can configure the old
DHCP server so that it will respond in a manner that will force clients to move
to the correct DHCP server pair? Your comments & suggestions are
greatly appreciated.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoListParagraph style='margin-left:20.25pt;text-indent:-.25in;
mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>-<span
style='font:7.0pt "Times New Roman"'>
</span></span><![endif]>Mike<o:p></o:p></p>
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