Recommended DHCP lease time?

[Cooky]

What's the recommended DHCP lease time?

Our server team set it to a week, but due to the increasing number of mobile devices that users bring in, we're exhausting our DHCP pools quickly.
Was thinking we can shorten the lease time to something like 8 hours.
Thoughts? Recommendations?

 

[theevilsharpie]

Unless your DHCP server is providing thousands of DHCP leases across very slow links, set it as low as you want. I usually set mine for a day, but, but 8 hours works as well.

 

[iNGEN2]

The general rule I always used was twice the average user's connect time. A quick dump of your router logs to spreadsheet can get you the average connect time.

 

[dawks]

The biggest 'downside' to going with a shorter lease time is the increase in network traffic, but if you're running a 100mbit+ network, I dont think its much of an issue. DHCP req's and acks are only a few packets, so its no like its going to flood the network.

A DHCP req is sent a 50% of the life of the lease IIRC.

 

[Nothinman]

Yea, you could probably set it for under an hour and not notice any ill effects since a DHCP renewal is usually just 2 packets per-client.

 

[spidey07]

Recommended time is as long as possible without running low on addresses. This should answer your scenario.