We had run 15 minutes lease time on /22 wireless public subnets for a few years without problem. We just moved our wireless subnets to private IPs and changed to 4 hours lease time this fall.
Dennis ----- Original Message ----- From: "Ryan Holland" <[email protected]> To: [email protected] Sent: Wednesday, September 30, 2009 4:43:30 PM GMT -05:00 US/Canada Eastern Subject: Re: [WIRELESS-LAN] wireless DHCP lease time Philippe, We saw improvement moving from 1 hour to 30 minutes with no foreseen adverse affects. We are testing a few subnets on 15 minute leases, as it would be more practical to avoid any "waste" of leases for the 5 minute email/facebook check on an iPhone/iPod-Touch. I'll let you know if we run into problems. Our setup is similar, with an external DHCP server running ISC, and we're of course using Aruba as well. Our aaa timers are 15 minutes (900 seconds). ------------------ Ryan Holland Network Engineer, Wireless CIO - Infrastructure 614-292-9906 [email protected] On Sep 30, 2009, at 4:33 PM, Philippe Hanset wrote: What a timely discussion! This morning we noticed that our pools (Aruba VLAN pools, 32* /24) were being filled from 70 to 90%. Our lease time is 3 hours. As most of you, we have been hammered by Iphone/Ipod-touch (~4000 registered at the moment) For a campus population of 30,000 (25,000 students 5000 fac/staff). Has anyone seen issues with 30 or 40 minutes DHCP leases on an Aruba infrastructure ? (we don't run DHCP on Aruba, but on ISC DHCP) What AAA timeout have you implemented? (show AAA timers... in our case we have 1800 sec) (we had to shorten the AAA timeout as well because our User licenses were being exhausted ... Iphone again ;-) Thank you Philippe Hanset Univ. of TN On Sep 30, 2009, at 2:52 PM, Steve Hess wrote: We run 4 /23's (one per class) with 4 day lease times. It's very tight right now for freshmen and sophomore's but lots of room for juniors and seniors. Each class is about 350-450 students. I'm looking to add another /23 per class to provide some head room. We run 4 day lease times for the forensic aspect of it. Definitely seeing more wireless devices this year. Upperclassmen are registering computers. Underclassmen are registering a computer (or two), an iPhone/iPod, and a gaming device. For those of you running the /22's and /20's, you don't see performance issues with broadcast domain's that large? Our wireless vendor (Alcatel/Aruba) highly suggested shrinking the broadcast domain (we had been running one /22 for all students). Steve heath.barnhart wrote: We run 30 minute leases for most of SSIDs, no problems. We saw an unexpected boost in wireless usage this semester though, and had to go from /22 networks to /20 to accommodate the new users and leave room for expansion. Heath Garrett Harmon wrote: We're running into some issues at the ramp up of a quarter with our DHCP lease time attempting to utilize the /24's we currently pool for our main essid. We moved from 1hr. to 30 minutes, but are still running out of leases occasionally. For instance, we have 160 users in a /24, but due to the transient nature of wireless/classes leases that are used for a brief moment the cycle isn't quite efficient enough. What is everyone else using for wireless DHCP lease times? I know I can just add another /24 to the pool, but the networks are not being utilized enough. We want to try 15 minutes but are wondering if we will start to run into issues related with that? Your input is greatly appreciated!! *Garrett Harmon* Network Engineer Office of Information Technology The Ohio State University 614.292.2122 (o) 614.747.5539 (c) ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/ . -- ----------------------- Steve Hess Network Administrator Wheaton College Phone: 508-286-3404 Fax: 508-286-8270 ----------------------- ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/ . Spam Not spam Forget previous vote ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/ . ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
