Change PoE/PoE+ Class


Hi,

I'm having some issues trying to power CISCO IP PHONES 99XX and their Key Expansion Module (KEM) connected to a switch B5. The symptoms are:

* CISCO IP phone 9971 is seen by the switch as a Class 4 Device, and when the KEM is connected to the IP phone the KEM works.
* But, CISCO IP phone 9951 is seen by the switch as a Class 3 Device, and when the KEM is connected to the IP phone the KEM doesn't work.

My question is:
Are there any command to change the PoE Class in the switch's ports?

Thanks for your help

3 replies

Userlevel 5
Hello,

Switch port specific configuration is not available.

While not a perfect fit, you might try the following approach:

set inlinepower management {realtime} module-number

This command sets the entire module to supply real time power requirements vs class or negotiated power at each port.

For more POE specifics:
https://extranet.extremenetworks.com/downloads/Pages/dms.ashx?download=baa51fcf-460d-4949-8d11-b0c7ee8e753a (Login needed)

Management of PoE Power to PDs 7-1 through 7-5

best regards,
-mike
Hi Michael,

Actually I have tested all the PoE commands, and also I have tested with some LLDP-MED commands, but didn't work. So, the conclusion must be that Cisco IP Phone with KEM and B5 switch aren't able to correctly negotiate PoE. What do you think?

Thanks for your help.

BR,
Santiago
Userlevel 5
Hello Santiago,

We have little understanding of how and why this fails to negotiate.
Experience (lots of mistakes) tells me it's early to establish incompatibility.

But I agree the prospects don't look good. I'm not optimistic.

-mike

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