[c-nsp] Power Redundancy in 3550 or 3750?

[Hakan Lindholm]

On Sat, 30 Jul 2005, Michel Renfer wrote:

> We saw the same issue with 3650 and RPS...
>
> cheers,
> michel
>
>> -----Original Message-----
>> From: cisco-nsp-bounces at puck.nether.net
>> [mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of Dmitry Valdov
>> Sent: Saturday, July 30, 2005 7:09 AM
>> To: Andrew Fort
>> Cc: cisco-nsp at puck.nether.net
>> Subject: Re: [c-nsp] Power Redundancy in 3550 or 3750?
>>
>> On Fri, 29 Jul 2005, Andrew Fort wrote:
>>
>>> Also, when you switch from RPS back to mains, the switch will power
>>> cycle; so power outages still require an outage, just that
>> you get to
>>> choose when it'll be.
>>
>> It's not true at least for 3550. We verified it..


Do you mean they _do_ power cycle when switching back from RPS, or _don't_ 
they?  And how many switches have you tested, and have Cisco confirmed 
they should/shouldn't reload?

In my lab of 2950's and RPS300's, the first switch didn't reload, the 
second one did.  And the next three switches also did reload.  Cisco TAC 
confirmed that they might reload.

As already noted, they are only for securing from uncontrolled downtime in 
case of internal power supply failure.  And to replace that internal power 
supply, you have to schedule some downtime anyway.


In my TAC case, I verified it was a RPS device issue, it wasn't a software 
version issue, but an "cisco internal" hardware "bug".  They replaced two 
of my switches to no good..

Some words from the discussions that time:

"The AC power supply is FAULTY even after plugging
  back in the AC power cable.  So when you push the
  RPS button, the RPS would stop supplying the power
  supply and the AC power supply would kick in but
  it takes a short time for the AC power supply to
  take over; but the little gap may reload the switch.
  It is what the bug means.  The AC power supply need
  redesign to kick in quicker."

"We suggest having the RPS and the switch be powered
  from the same power supply."

"Both the AC and DC-to-DC converters are something
  that we are buying from different vendors. All of
  them are within the limits that we set."



So, we are not using any cisco RPS'es today.

Unfortunately, we don't have any other solution in place neither.
But the internal AC power supplies are not dying either.

/H