RE: [WIRELESS-LAN] wireless DHCP lease time
We are running a 10 minute lease on our 2 /21's with no issues that I know of. Generates a lot of logs though. I wouldn't want to go much shorter. -Neil -- Neil Johnson Network Engineer Information Technology Services The University of Iowa Work: 319 384-0938 Mobile: 319 540-2081 Fax: 319 355-2618 E-mail: neil-john...@uiowa.edu From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:wireless-...@listserv.educause.edu] On Behalf Of Garrett Harmon Sent: Wednesday, September 30, 2009 1:09 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: [WIRELESS-LAN] wireless DHCP lease time 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/. ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
RE: [WIRELESS-LAN] wireless DHCP lease time
Sounds like a great use case for ip mobility... what are you running for wireless controllers? From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:wireless-...@listserv.educause.edu] On Behalf Of Garrett Harmon Sent: Wednesday, September 30, 2009 11:09 AM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: [WIRELESS-LAN] wireless DHCP lease time 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/. ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
RE: [WIRELESS-LAN] wireless DHCP lease time
Garret, Wireless networks tend to be used in bursts. Most of the time they are underutilized. However, we try to build them for worst case scenario situation. Sounds to me like adding another /24 might be your best bet. Also might depend on how users connect. Can anyone come in and connect? We ran and continue to run into issues with this because of the iPhone and/or devices that always try to connect to a nearby network so long as it is open. Or do your users have to authenticate? If the latter, then there is nothing you can do but expand the pool. Otherwise you might have to get creative and force users to auth before they connect. Thanks. Jorge Bodden From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:wireless-...@listserv.educause.edu] On Behalf Of Garrett Harmon Sent: Wednesday, September 30, 2009 2:09 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: [WIRELESS-LAN] wireless DHCP lease time 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/. This electronic message is intended to be for the use only of the named recipient, and may contain information that is confidential or privileged. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution or use of the contents of this message is strictly prohibited. If you have received this message in error or are not the named recipient, please notify us immediately by contacting the sender at the electronic mail address noted above, and delete and destroy all copies of this message. Thank you. ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
Re: [WIRELESS-LAN] wireless DHCP lease time
We're actually running mobile IP on our Aruba controllersand love itbut that doesn't really affect the iphone users that connect and update facebook then walk somewhere without coverage essentially trahsing that IP for another 29 minutes. In our most populated stack we have 10 /24's hence the hesitation to add more, but will likely have to. We're going to try 15 minute leases to try and gain a bit more utilization, along with adding another /24. Thanks for the input everyone! -Garrett On Sep 30, 2009, at 2:15 PM, Jason Appah wrote: Sounds like a great use case for ip mobility… what are you running for wireless controllers? From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU ] On Behalf Of Garrett Harmon Sent: Wednesday, September 30, 2009 11:09 AM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: [WIRELESS-LAN] wireless DHCP lease time 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/ . 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/.
RE: [WIRELESS-LAN] wireless DHCP lease time
Garrett, we run with 15 minute lease times on the wireless network, the only minor issue we came across was the default ARP table timeout was 30 minutes, which would normally be fine, so we needed to lower that on the network switches to match. Many Thanks Peter -Original Message- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:wireless-...@listserv.educause.edu] On Behalf Of Jason Appah Sent: 30 September 2009 19:15 To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] wireless DHCP lease time Sounds like a great use case for ip mobility... what are you running for wireless controllers? From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:wireless-...@listserv.educause.edu] On Behalf Of Garrett Harmon Sent: Wednesday, September 30, 2009 11:09 AM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: [WIRELESS-LAN] wireless DHCP lease time 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/. ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.409 / Virus Database: 270.13.115/2405 - Release Date: 09/30/09 10:35:00 -- Heriot-Watt University is a Scottish charity registered under charity number SC000278. ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
Re: [WIRELESS-LAN] wireless DHCP lease time
We had similar issues, and have found a happy middle with 40 min max lease time with our controllers (Aruba) having a user timeout of 38 min. Ken Connell Intermediate Network Engineer Computer Communication Services Ryerson University 350 Victoria St RM AB50 Toronto, Ont M5B 2K3 416-979-5000 x6709 -Original Message- From: Garrett Harmon harmon@osu.edu Date: Wed, 30 Sep 2009 14:08:49 To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: [WIRELESS-LAN] wireless DHCP lease time 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/.
Re: [WIRELESS-LAN] wireless DHCP lease time
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!! Hi, We give out 30 minute leases and peak at about 700 used leases with 600 peak concurrent wireless users at the moment. We have two /22 nets (enough for when the usage picks up towards deadline time). Two things: - If your using ISC DHCPd in failover mode, I believe each client's 'new' lease is for the MCLT time (renewals are then for whatever you actually set the lease time to). - We do: option space MSFT; option MSFT.release-dhcp-lease-on-shutdown code 2 = unsigned integer 32; ... to try to pursuade windows machines to explicitly release their leases if they are shutdown while still in wireless range - there must be an equivalent to set this DHCP option if you're not using ISC dhcp. -James -- James J J Hooper Network Specialist Information Services University of Bristol http://www.wireless.bristol.ac.ukhttp://www.jamesjj.net -- ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
Re: [WIRELESS-LAN] wireless DHCP lease time
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/. -- Heath Barnhart Asst. Systems and Networking Admin Information Systems and Services Washburn University Topeka, KS 66621 ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
RE: [WIRELESS-LAN] wireless DHCP lease time
Hey all, Very much the same case at UBC. We have 30 minute DHCP timers (so 15 minute requests) active on 12x /21's... Without it we would be hosed. We'd like to go lower, but the load on the controllers (DHCP proxy) and the DHCP server (old SPARC) would likely become a problem. Thanks, Ian Procyk UBC IT Connectivity Infrastructure 604-8275707 -Original Message- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:wireless-...@listserv.educause.edu] On Behalf Of heath.barnhart Sent: Wednesday, September 30, 2009 11:40 AM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] wireless DHCP lease time 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/. -- Heath Barnhart Asst. Systems and Networking Admin Information Systems and Services Washburn University Topeka, KS 66621 ** 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/.
Re: [WIRELESS-LAN] wireless DHCP lease time
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/.
Re: [WIRELESS-LAN] wireless DHCP lease time
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/ . ** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
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 holland@osu.edu 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/.
Re: [WIRELESS-LAN] wireless DHCP lease time
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 holland@osu.edu To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU 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 holland@osu.edu 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/.
Re: [WIRELESS-LAN] wireless DHCP lease time
Not sure if this is the case for anyone, but one of the issues we ran into with lease shortages was related to maybe on oversight on our part. The ISC dhcp has a max-lease-time and a default-lease-time value. While wireless was set to hand out 30-minute leases (default- lease-time), the max-lease-time globally was set to 24 hours. We had a /22 that was being fully consumed by 9:30AM each weekday, and were seeing leases through the night, that, when cleared, wouldn't be renewed until the next morning. With Windows OSes, they took the 30- minute lease and went on their way. Apple devices request a 90-day lease, and so were being handed out a 24-hour lease, since that's what the max-lease time was set to. We shortened the default and max-lease times down for the wireless dhcp config to 15 minutes, and now run with 40-50% of available leases free through the day for the /22. -- Richard On Sep 30, 2009, at 3:33 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/ . ** 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/.
Re: [WIRELESS-LAN] wireless DHCP lease time
We have quite a few wireless networks set to 15 minutes with no adverse affects. Dale On Sep 30, 2009, at 3:43 PM, Ryan Holland wrote: 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 holland@osu.edu 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/.
