[CentOS] dhcp lease-time

Ljubomir Ljubojevic office at plnet.rs
Thu Jan 5 10:21:45 UTC 2012

On 01/05/2012 09:54 AM, John Hodrien wrote:
> On Thu, 5 Jan 2012, Timothy Murphy wrote:
>> Why is the default lease-time set to only 10 minutes (600 seconds)
>> in /etc/dhcp/dhcpd.conf (CentOS-6.2) as distributed?
> I assume the dull answer is: because that's what Redhat set it to.
>> Why is not set to a much longer time?
> What length do you think the correct default should be?
>> Is there any disadvantage in doing that?
>> Or conversely, is a short lease-time safer in some way?
> Short lease times work better with very transient devices, since the IP
> address is returned to the pool much faster when a machine disconnects but
> doesn't release the DHCP lease.

Also, there should be distinction between default and max lease time. 
DHCP server uses default lease time too force DHCP client to "chek-in" 
in that time period. If device does not respond, then DHCP server will 
reuse that IP.

Max lease time is used to allow DHCP client so the traffic is lesser and 
after that time DHCP client will ask for renewal of the IP.


Ljubomir Ljubojevic
(Love is in the Air)
PL Computers
Serbia, Europe

Google is the Mother, Google is the Father, and traceroute is your
trusty Spiderman...
StarOS, Mikrotik and CentOS/RHEL/Linux consultant

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