We’ve still got some injectors. We stock PowerDsine 9001G’s because they support at power.
One issue with using these vs. a PDU is that they can’t be remotely powered off if an AP needs to be power cycled. We’ve had some instances where an injector seemed to go bad such as an AP repeatedly going down once a week or so until the injector is replaced. Otherwise I’d say they are reliable enough. PoE ports obviously go down sometimes too. In terms of reboots we had tracked them before by a trigger on the reboot number. Every time an AP reboots the count increments up and we would get a warning. We’ve switched from tracking reboots to using a trigger based on an AP being down for more than 5 minutes. It’s proven to be a better indicator of a service problem. We still check for high reboot counts but don’t send out warning. From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[email protected]] On Behalf Of Jeremy Mooney Sent: Wednesday, August 31, 2016 6:50 PM To: [email protected] Subject: Re: [WIRELESS-LAN] Do you have POE everywhere? All normal switch ports are PoE now, between APs, phones, and cameras. We do still have some injectors though. 1. Only a handful - locations without a normal switch (just VPN router for remote, or fed from media converter if the location only has fiber). We have a lot of security cameras fed via injectors though (the PTZ + fan + heater ones that are rated 60W). Never had issues with either being noticeably different than direct-from-switch. I believe there are a couple daisy-chained VoIP phones using them due to lack of in-wall cabling. 2. No, either LP2521s or built into the media converter (S-1100P-SFP I think). They actually seem to care less about power glitches than the Cisco switches. 3. If an AP reboots because of a power glitch it usually takes long enough to trigger our AP-is-missing monitoring temporarily, but not quick reboots. Otherwise just the controller's ordered list of connection times (and listing uptimes). Haven't ever noticed them abnormally low on either field though. On Wed, Aug 31, 2016 at 8:42 AM, Todd M. Hall <[email protected]<mailto:[email protected]>> wrote: 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]<mailto:[email protected]> 662-325-9311<tel:662-325-9311> (phone) ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. -- Jeremy Mooney ITS - Bethel University ********** 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/.
