Garbage collection?

Peter Laws plaws at
Wed Sep 9 14:30:47 UTC 2009

Simon Hobson wrote:

> 1) The most obvious is to add more addresses, though I realise this 
> may be difficult.

Next month.  :-)  We'll actually divide campus into sections with a pool 
for each.

> 2) Shorten lease times. If you have a high churn rate, then it's 
 > quite likely that you have a lot of leases that are active but the
 > client has walked away. There is nothing the server can do a

Exactly what we did - 3600 to 1800.  May yet drop it to 900.

And yes, literally walked away.  As near as we can tell iPhones (and iPod 
Touches) default to having WiFi on, so some are walking in and out of 

Three years ago the pool was 1/4 what it is now, currently a /19, and 
leases were 4 hours.

Thanks to both of you for explaining the leases file cleanup.

Peter Laws / N5UWY
National Weather Center / Network Operations Center
University of Oklahoma Information Technology
plaws at
Feedback? Contact my director, Craig Cochell, craigc at Thank you!

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