3850 Best Stack Power Mode Power-Sharing or Redundant?

[NPT_2]

Is it better to use power-sharing or Redundant Power modes on a 3850 Switch Stack.

Our configuration is as follows:

3x WS-C3850-48T Switches (Non POE with 48x Copper Gig and 4x 10 Gbit Uplinks (No POE Ports)

2x 350 Watt Power Supplies in each Switch (6 Power Supplies total)

Power Stack and Stack 480 GBit Cabled in full ring.

Is it safer or better to use power-sharing or Redundant mode?  What are the advantages of each one.  I'm thinking its not going to be making a lot of difference since we are not oversubscribing or even running POE on these switches. 

What do you think?

Jim

[Reza Sharifi]

Most Cisco switches by default use redundant mode, which means one power supply is working and the other one is on stand-by in case the first one fails. In your case, it should not matter, but in   redundant mode you know for sure one power supply is running the switch and if you have to replace  a failed one you don't have to worry about the switch running out of power which can happen in a sharing mode.  As for power stacking, it is good idea, as it gives you an extra layer of protection in case a switch loses power completely.

HTH 

[NPT_2]

So if I read that correctly, it sets redundancy on power supplies on a per switch basis and not on the entire power stack?  If that's the case I'll just run in redundancy mode as I don't see how with data only I would exceed one power supply draw. 

[Reza Sharifi · Accepted solution]

Correct. So, power redundancy and power sharing commands apply per switch with multiple power supplies.  Power stacking is for sharing power between multiple switches, so if one switch gets completely unplugged from the outlet, the other switches will give it power via stacking cable. 

HTH