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</o:shapelayout></xml><![endif]--></head><body lang=DA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>I have just taken over a two node DHCP setup, running in failover configuration.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>We have just recently discovered issues with some clients not getting an IP address.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>What I see in the logs:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Server 1 logs: load balance to peer<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Server 2 logs: peer holds all free leases<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>For the pool in question, server 2 shows this:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sc-dhcp-02 dhcpd: balancing pool b23e820 x.x.x.x/21 total 2000 free 2000 backup 0 lts -1000 max-own (+/-)200<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Server 1 shows nothing for this pool.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Much to my surprise I discovered that the dhcpd.master configuration files are not at all identical on the two servers.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>For the address pool in the example:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Server 1:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>subnet x.x.x.x netmask 255.255.240.0 {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option dhcp-parameter-request-list 1,3,6,15,42,43,54,128,201,230,232;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US># default-lease-time 900;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US># max-lease-time 1000;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option routers x.x.x.x;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option subnet-mask 255.255.240.0;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option domain-name-servers x.x.x.x;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option AgentID 10.23.16.1; # Option 54<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option NTP-server 88.83.68.3; # option 42<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US># pool {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US># failover peer "dhcp-failover";<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> range 10.23.16.16 10.23.31.254;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US># deny dynamic bootp clients;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US># }<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>}<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Server 2:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>subnet x.x.x.x netmask 255.255.240.0 {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>option dhcp-parameter-request-list 1,3,6,15,42,43,54,128,201,230,232;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US># default-lease-time 900;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US># max-lease-time 1000;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option routers x.x.x.x;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option subnet-mask 255.255.240.0;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option domain-name-servers x.x.x.x;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option AgentID x.x.x.x; # Option 54<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> option NTP-server x.x.x.x; # option 42<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> pool {<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> failover peer "dhcp-failover";<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> range 10.23.16.16 10.23.31.254;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> deny dynamic bootp clients;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US> }<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>}<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>As you can see, server 2 does have a “failover peer” statement, server 1 does not.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>The configuration above is similar to a lot of other pools in the master config.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I have no idea why anyone would configure the servers like this, but it’s obviously not working.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Any idea on how to get addresses to the clients?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Thanks!<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black;mso-fareast-language:DA'>Med venlig hilsen/ Best regards<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black;mso-fareast-language:DA'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:20.0pt;font-family:"Georgia","serif";color:#FF330D;mso-fareast-language:DA'>Jesper Nørgaard</span><span style='color:black;mso-fareast-language:DA'><o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Georgia","serif";color:#B6B6AE;mso-fareast-language:DA'>IT System Administrator</span><span style='color:black;mso-fareast-language:DA'><o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>