Solved: 3750 48PoE with a RPS2300 - PoE lockout

williamsryan · ‎10-03-2008

Hi, I have a 48port 3750 PoE switch running ip base 122-46.SE. The switch is connected to RPS2300.

The issue is when I test the RPS failover, the switch fails over to the RPS ok, however when it fails back by manually pushing the standby and active button, the switch shows the following error on all ports regardless of if there is anything plugged into that port, or if it is non-PoE, and the PoE LED on the front flashes amber.

%ILPOWER-3-CONTROLLER_PORT_ERR: Controller port error, Interface Fa1/0/46: Power Controller reports power supply VEE under voltage and lockout

As a result the PoE devices (phones in this case) are off. The way I clear the issue is either to reboot the switch or issue the following on all ports.

switch(config)#int range f1/0/1-48

switch(config-if-range)#power inline never

switch(config-if-range)#power inline auto

Any ideas as to why it does this, as it sort of negates the point of RPS if all my Phones go off when power is restored to the switch and taken off the RPS.

thanks

Ryan

Sushil Kumar Katre · ‎10-05-2008

Hi Ryan,

As pointed by Kevin this is a normal behavior. Even I was surprised when I encountered this for the first time.

We need to understand that RPS is not UPS. It's supposed to support the devices in case the internal power supply fails and not in case of the power failure itself. It's a well know issue.

Have a look at limitations of RPS -

http://www.cisco.com/en/US/docs/switches/power_supplies/rps2300/release/notes/OL12497.html#wp899726

Its actually a BUG :) CSCdx81023 without a workaround.

-> Sushil

View solution in original post

Kevin Brennan · ‎10-03-2008

Hi Ryan,

I believe that this is behaving as designed.

The function of the RPS is to keep your switch(es) running if the switch psu fails untill you have a maintenaince window to replace the failed supply.

It is a failover solution and not a failback solution.

This is from experience with 3550 switches a few years back, but I think the functionality is still the same.

Kevin

Sushil Kumar Katre · ‎10-05-2008

Hi Ryan,

As pointed by Kevin this is a normal behavior. Even I was surprised when I encountered this for the first time.

We need to understand that RPS is not UPS. It's supposed to support the devices in case the internal power supply fails and not in case of the power failure itself. It's a well know issue.

Have a look at limitations of RPS -

http://www.cisco.com/en/US/docs/switches/power_supplies/rps2300/release/notes/OL12497.html#wp899726

Its actually a BUG :) CSCdx81023 without a workaround.

-> Sushil

williamsryan · ‎10-06-2008

Hi Guys,

Thanks for the replies to my post. I suspected that it may be normal behaviour as I understood it was an RPS not a UPS. I was just suprised that it was only the PoE side of things that was affected by swapping back to internal PSU. Normal port function for non-PoE device was unaffected.

Thanks again.