POE Port was denied Power_MR57-AP

[SundarRRH]

Hello Everyone,

we have connected 21 number of  MR57 access points in MS355-48X switch having 740 W power Budgeted & 296.1 W consumed .for every one week(approximately) the MR57  access points are disconnecting from the Switch and showing "POE Port was denied Power "error in the interface.

we have recycled the port from dashboard , done jack-in jack out the cable  from switch and we have tried connecting the same AP in other interface in same switch and other switch also, but no luck getting same error .

After all the troubleshooting's Access point getting heated and not powering On

can anyone help us with the above Issue and let us know how many APs can we connect to MS355-48X switch with power 740 W budgeted & 296.1 W consumed  .

Note : On an average each Access point consuming 14 W from interface in switch

Thanks 

SundarRRH

[cmr]

@SundarRRH what firmware are you running?  We recently ran into an odd PoE bug after upgrading from 14.33.1 to 15.21.1.

One PoE camera (not a PoE+ device that uses CDP or LLDP) just refused to power up, no message or anything.  We moved it to another port and it was fine.  At another site one PoE port also stopped delivering power after an upgrade.  We are working with support on both as we don't believe it is a hardware issue.

Are your cameras spread across the switch or all plugged into one end (ports 1-21 for example)?

[SundarRRH]

Hello @cmr , Thank you for prompt reply.pls find the below response

what firmware are you running? - to be clear end devices are Access Points running with firmware MR 28.7.1

Are your cameras spread across the switch or all plugged into one end (ports 1-21 for example)? all Plugged into one end i.e.. from port 1 to 21

[cmr]

@SundarRRH I would do a few things:

• Spread them out across the switch ports
• Upgrade to at least 29.5.1 as there have been a lot of unspecified performance and reliability improvements.

Also what switch firmware are the MS355s running?

[SundarRRH]

@cmr ,as  suggested by you we'll spread them out across the switch ports  and upgrade the firmware 

MS355 - 48X switch is running with 15.21.1 firmware version which is up to date 

[Madhan_kumar_G · Accepted solution]

Hi,

If your network permits, Do a reboot of the switch. This can be a workaround. And look for upgrading the firmware as a solution. If upgrade didn't help, open a TAC case and work towards RMA.

[SundarRRH]

Hi Madhan,

Thanks for your response ,we have spare of access points ,replaced the faulty one and raised RMA with Merakli support ,as Meraki  doesn't  have any RCA for the Issue .

[TBHPTL]

MR57 require more than af or at at full operation if you are not using the USB ports you should budget 30 W of power for each MR57 at a minimum. 802.3at  at 30wx21=630W. Cable lengths per AP will vary drastically, best practice is to assume the maximum draw. as your APs power will fluctuate depending on the Tx power and number of users connected, channels in use,  etc. etc. etc. etc.

A 355-48X should be using a 1025W PS not a 740...

[SundarRRH]

hi @TBHPTL ,

Thanks for the response ,,