Re: Cache Battery question

[DrFranken <midrange@xxxxxxxxxxxx>]

I have asked people who know these things for further clarification. I 
will pass it along as it becomes available.

However, I cannot imagine IBM selling a multi-million dollar machine to 
a large enterprise such as a bank for example that requires its cache 
batteries to be swapped out every time they have a power outage. I have 
personally worked on machines with over 100 of these which would 
translate to over $10,000 per outage!

Even harder to believe is that IBM would sell that machine to them and 
**NOT** tell them this is a requirement. (Because they do not tell them 
this.)

Even more harderer still to believe is that IBM Legal would allow them 
to sell this AND not tell them.

        - Larry "DrFranken" Bolhuis

www.frankeni.com
www.iDevCloud.com
www.iInTheCloud.com

On 5/16/2015 4:02 AM, Holger Scherer wrote:

> ok, lets name it like this - most of the controllers *Try* to recharge
> the battery, but most of them do not a good job. We checked this on
> several older or newer controllers using a break out cable and a voltage
> monitor.
>
> For example, the old 2740/2748 do not really charge
> (as they do not have electronics for this), they try to keep 3.6V
> which is not enough for 3.6V Batteries.
>
> Same with the newer LiIo controllers which do not do a temperature
> measure from the battery (which does have the cable). They send some
> millivolts to keep the voltage, but they cannot recharge a
> battery at a 70% level... If there was an unplanned outage, exchangeing
> the battery is a good idea.
>
> -h
>
>
>
>
> Am 16.05.15 um 08:02 schrieb DrFranken:
> > That's not correct, the controllers DO charge the batteries. Think about
> > what would happen if they didn't, you lose power for a few hours and
> > your server goes down. The battery holds the cache during that time and
> > of course discharges partially in that effort. When power is restored
> > you bring up the system no problem.  If the batteries did not get
> > charged by the controller then the remaining battery life might not be
> > sufficient to hold up the cache during your next outage.