Log lease time

Gregory Sloop gregs at sloop.net
Sat Dec 16 02:46:43 UTC 2017

So, thread drift... :)
Really, what I've found, via other looks at the logs.

I have a few [perhaps a dozen] machines that are DHCPREQUEST'ing vastly more often than they should.
Yet if I look at the leases file, all except a couple are getting the proper 4h lease.
Yet, the most problematic one is DHCPREQUEST'ing about every 10 seconds! [It varies, what I've seen anyway, from 8s to around 60s.

So, I'd assume this is a client problem, until proven otherwise.

Turns out most of the top problem clients are on Wifi. [Ubiquiti Unifi, multiple buildings/multiple AP network.]
We're not aware of these clients falling off the network and then getting back on - though I suppose I can't say for sure that's not happening.

Does anyone have some great tips as what might be causing the issue?


If you declare as a global parameter the max lease time, min leas time and default lease time even if the end user device may have it's own lease time parameter pre-configured, it will obey to the global parameter you will set.
I had the same problem with some of my devices but after declaring with the same lease time for max,min and default it was fixed.

On 15/12/2017 10:37 PM, Gregory Sloop wrote:
Log lease time Is there a way to write into the logs the lease time offered/given for each lease?

Why, you ask? I've got some clients that are getting very short leases, and I'd like to understand why. 
Knowing more detail about what clients are getting for leases would be, I think, helpful in figuring it out.

I assume it's possible with some level of debug, but it would be helpful to know at what level I'll get this...if at all...
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