Jim, Why do you want to poll so often? We use WCS and left the client polling at the default of 15min. For troubleshooting purposes we rely mainly on RADIUS logs and do the actual client troubleshooting directly from the controllers.
Hector Rios Louisiana State University -----Original Message----- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[email protected]] On Behalf Of Jim Gogan Sent: Monday, May 18, 2009 11:27 AM To: [email protected] Subject: [WIRELESS-LAN] Airwave performance question We have been dealing with some Airwave performance issues for quite a while, and wanted to compare results with others out there that have Airwave installed and use it to support their user base. Any information would be very helpful. We have about 1800 access points across about 30 controllers. The vast majority of these APs are thin Cisco with some small installs of Aruba (less than 100). We peak around 8500 concurrent wireless users during the fall and spring session. Our problem has to do with polling times for User Data, and the expected time for newly connected machines to be reflected as associated within Airwave. We want nothing less than 5 minute polling period for user data. We have set everything else to 30 minutes in order to reduce load on our server (which is a dual quad core Xeon with 16 gigs of RAM and (2) 15k RPM SAS drives in RAID 0). We are seeing what we would consider less than stellar results. During the school year, it would take this box, at times, over 20 minutes to actually show a user as associated. That means, as we understand it, the data for troubleshooting the connection is 20 minutes old. Given our expected level of service and support, this is not acceptable. We are expecting that the Airwave server should show a new user within 5 minutes for the majority of the time, and be no more than 7 or 8 minutes worst case (explained: if the server just finished polling a controller, and a new user connects, then it would take 5 minutes for Airwave to discover this device, and another 2 to 3 minutes to parse the data. If the user connects just prior to a poll, then it would be possible to see the user prior to 5 minutes). The questions we have for this group are: How often are you polling user data? Have you actually benchmarked this to verify that the user is showing as associated close to the time that you have set for user polling? If so, what are your polling times for user data, and what is the spread of times you saw this device as associated? Is there anyone actually polling their controllers with less than 5 minute polling periods, and have verified performance (connect time to associated time in Airwave)? Our test is this: We take a device that was previously known to the network that has wireless disabled. We locate the device historically within Airwave (search on the MAC address). We actually click on the result, and bring up details on that MAC address. We then turn on the machine's wireless and start a timer. We keep hitting refresh until we see the device shown as associated. That is when we record the time. A few points on this: results are dramatically improved when the load is low. Right now, we are seeing sub 5 minute times. This is because we only have 3000 users on the wireless network now. This is not the case when we have 7000+. We have also been working a lot with Airwave over this, without any real change in these results. We are wondering if people just consider this acceptable performance? Comments/questions/concerns? Thanks in advance! -- Jim Gogan Director, Networking ITS Communication Technologies UNC-Chapel Hill ********** 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/.
