WS-C3850 Switch Stack and Power issue's

[sdawson35]

Hi,

We have a 7 stack , stack of 3850's. The stackwise 480 cables are correct as are the power cables.

Physically Switches 1-4 are connected and Switches 5-7 are connected however we are getting an error in the log

 Jul 18 17:35:44 BST: %PLATFORM_STACKPOWER-4-REDUNDANCY_LOSS: Switch 4's power stack lost redundancy and is now operating in power sharing mode

sh stack-power
Power Stack           Stack   Stack    Total   Rsvd    Alloc   Unused  Num  Num
Name                  Mode    Topolgy  Pwr(W)  Pwr(W)  Pwr(W)  Pwr(W)  SW   PS
--------------------  ------  -------  ------  ------  ------  ------  ---  ---
Power2-7              SP-PS   Ring     3575    281     *2512   *782    5    5  
Power1-4              SP-R    Stndaln  715     45      670     0       1    1  
Power2                SP-R    Ring     2145    756     1389    0       3    3  

*Marked power numbers are estimated due to the
 Power Stack member's absence in the data stack.

stack-power stack Power1
 mode redundant
stack-power stack Power2
 mode redundant
!
stack-power switch 1
 stack Power1
stack-power switch 2
 stack Power1
stack-power switch 3
 stack Power1
stack-power switch 4
 stack Power1
stack-power switch 5
 stack Power2
stack-power switch 6
 stack Power2
stack-power switch 7
 stack Power2

No idea what we are doing wrong, can anybody help ?

Regards

Scott.

[Georg Pauwen · Accepted solution]

Scott,

hard to say. Are all switches configured for redundancy mode (mode redundant) ? I don't want to be cheap, but have a look at the document below:

https://supportforums.cisco.com/document/72421/troubleshooting-tips-3750x-stack-power-feature

[sdawson35]

The power ports on switch 4 in the stack were both shut down, wern't aware they could be !!, sorted now thanks :-)

[EmmanuelJack]

Can you please share with us how you resolved it.