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I've allocated ip's to some systems through dhcp and then made entries in dhcpd.conf for reservation so that these ip's are not allocated to other macs. But when the system with reserved ip is offline and another client make dhcp request the reserved ip is alocated to it. My dhcpd.conf is following.

ddns-update-style interim;
ignore client-updates;
subnet netmask {
range ;
option routers          ;
option subnet-mask      ;
option time-offset                -18000;
max-lease-time 10000000;
option domain-name "inclined";
option broadcast-address;
host inc10 {
hardware ethernet 00:50:56:29:E8:F7 ;
fixed-address ;
host inc12 {
hardware ethernet 00:0C:29:81:A5:C1 ;
fixed-address ;
host inc23 {
hardware ethernet 00:0C:29:86:A6:72 ;
fixed-address ;
host inc34 {
hardware ethernet 00:0C:29:92:17:E3 ;
fixed-address ;

Suppose host inc34 is down and another new host requests an ip then is allocated to it. I don't want dhcp to ever reallocate reserved ip to other hosts. Any suggestions are much appreciated. Thanks

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1 Answer 1

up vote 4 down vote accepted

The answer would be to put the IP's of the machines with static IP's outside the range allocated - ie fixed-addresses do not need to be in the "range" pool.

In your case the easiest solution might be to change the range to


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