John Rumm wrote:
On 26/09/2020 14:18, Harry Bloomfield wrote:
John Rumm laid this down on his screen :
On networks with lots of devices connecting and disconnecting it can
make sense to lower the DHCP lease time to allow addresses allocated
to now dormant devices to be re-used sooner.

That makes sense, I did always wonder why the lease time was adjustable.

Worth noting that with much modern kit it may preserve a cache of MAC /
IP pairs even after lease expiry, so it can re-issue the same address
later where possible (although it can still re-allocate and address if
the lease has expired and it has run out of free pool addresses to meet
the current demand)

Always true in my experience with routers over the past several years,
the router always assigns the same IP to a given MAC address unless you
explicitly tell it not to.

--
Chris Green
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