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"If one fails, the other can take over and manage the full address
space."<br>
<br>
Be warned that only HALF of the address space is "automatically"
taken over by the surviving DHCP process (assuming the failover team
consists of 2 servers) :<br>
<i>"If one server fails, the other server will continue to renew
leases out of the pool, and will allocate new addresses out of the
roughly half of available addresses that it had when
communications with the other server were lost. "</i><br>
<br>
v4.2.0-P1 option "auto-partner-down" does not work for now, then
imposing to MANUALLY edit the leases file to set the surviving
server into "PARTNER-DOWN" state (see dhcpd.conf help file).<br>
<br>
Therefore, the failover efficiency depends greatly on the clients
requests rate : I had a big wireless infrastructure that, whenever a
controller shuts down, half of the 1000 APs request their address
back - until you have a more than 2000 addresses subnet, some APs do
not get their IP.<br>
<br>
My main advice concerning failover (until partner-down state is
really automatized) : use subnets large as twice as needed (if you
have 200 expected clients, set for a /23 subnet at least).<br>
<br>
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