Re: 6618 drives for model 270

[Larry Bolhuis <lbolhuis@xxxxxxxxxx>]

> they are 15K drives. 

Well you didn't SAY that!

15K RPM drives make too much heat and draw too much power for the 270 in 
any location except a FC 5095/0595 drawer. Believe me on this one as I 
tried 15K RPM IBM drives in FrankieIII and had big troubles. (Also got 
warnings from 'people who know' in Rochester that this was beyond 
'unsupported' and into 'dangerous' territory) 

OK It's possible that BCC found some lower power draw units but that 
would make me worry in another way - Reliability of the drive.  Also 
even though I can only go 10K in FrankieiIII I have never had a disk 
performance issue. (Maybe that's the 2780 RAID card or the 56 drive he's 
got, not sure.)

As to "A" and "B" sides you are correct. Unfortunately IBM frequently 
ships PTFs that automatically perm apply because removal would be fatal 
so they prevent that. Can't say if such a disk PTF would be one to get 
perm applied but you never know.  Also the "A" and "B" are for microcode 
only, for O/S and other PTFs you need to RMVPTF if it's still temp 
applied and then (usually) re-IPL.

 - Larry



Joe Pluta wrote:
> Well this just sucks.
>
> The primary reason I want to go with the BCC drives is that they are 15K
> drives rather than the 10K IBM drives.  This machine tops out at V5R4; I
> wonder if I should just apply V5R4 and the latest cumes and then never apply
> another PTF.
>
> Speaking of PTFs, isn't that what A and B sides are for?  Isn't there a
> procedure to apply a PTF and if it smokes, to go back to the pre-PTF state?
>
> Joe
>
>   
> > From: Larry Bolhuis
> >
> > We had this exact thing happen to customers using BCC drives. Install
> > PTF *poof* drive goes away and it was in a 270. Luckily they had just
> > one so RAID kept them alive until a replacement from BCC arrived that
> > was compatible with the PTF. (The drive had to be purchased by the way
> > it was not sent as a replacement for a failed drive.) As I understand
> > it, the PTF required some particular operation that the older BCC drive
> > didn't support, when the drive wouldn't answer it got voted off the
> > island.
> >
> > IBM Would never do that to their own drives because they know what they
> > can and cannot do.
> >
> >