We still have a few power injectors left in small places that have not been reworked with new switches and APs. We have always used PowerDsine rack-mount power injectors (6, 12, & 24 port models with various power output specs). They were quite useful from a management standpoint (they come with SNMP-based management software that can show power draw and can power off/on individual ports plus other stuff we rarely used). They also allowed to power the APs without having to purchase an entire switch or blade that did PoE. The PowerDsines were much cheaper than the difference in price between a non-PoE switch and a PoE switch. Also, with older locations AP density was much lower than what we now install. So we had some buildings with very few APs (e.g., 4 or 9) and we could buy a large switch to take care of the wired ports and a small PoE injector for the APs. They were very reliable.
Now that VoIP phones are taking over our world, we only use PoE switches now and use them to also power our APs. We are a Cisco shop. The PowerDsine units do not mask the CDP information passed to the switch from the APs. BTW: MicroSemi bought out PowerDsine some years ago. See: http://www.microsemi.com/products/poe-systems/poe-systems Our monitoring of AP reboots is mainly done via SYSLOG analysis. Our real-time monitors only poll every 5-10 minutes and are very likely to miss many AP reboots since they take about a minute to complete. But, we do notice APs down on the monitors all along. However, since we are logging all AP stuff to our SYSLOG servers we can easily scan them for reboots and create a table of what AP is doing what. In addition, since we run the HP/Aruba/Airwave AMP wireless management software, it can also report uptime for all APs. A quick scan of those with very short uptimes will also give you the list of ones that are constantly rebooting. However, the SYSLOGs are the only source we have that can give us the frequency of theses reboots. John Watters Network Engineer, Office of Information technology The University of Alabama A115 Gordon Palmer Hall Box 870346 Tuscaloosa, AL 35487 Phone 205-348-3992 [email protected] -----Original Message----- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[email protected]] On Behalf Of Todd M. Hall Sent: Wednesday, August 31, 2016 8:42 AM To: [email protected] Subject: [WIRELESS-LAN] Do you have POE everywhere? Do you have POE in every location or are there some small locations that still use injectors? If you have some injectors left, I have a few questions. 1. How reliable are they? 2. Are your injectors made by your wireless vendor? 3. Do you have a way to monitor how often your APs reboot? The reason I'm asking is that I just discovered that we have some APs that are rebooting frequently and they are all in locations that still have injectors. I expanded some home-grown code and started graphing AP uptime as well as lwapp/capwap uptime. (Found issues with lwapp/capwap uptime in a few locations as well) -- Todd M. Hall Sr. Network Analyst Information Technology Services Mississippi State University [email protected] 662-325-9311 (phone) ********** 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/.
