DASD PUMP failure (was:RAID failure) -- MIDRANGE-L

At 05:41 PM 1/27/98 -0700, you wrote:
>
>I did have one occasion several years ago where they came to me and said
>they had tried the pump but it failed.  When I went to look it had
>failed because of a media error on the tape.  I cleaned the drive, used
>another tape, and the pump was successful the next time.
>
As I say on my COMMON pitch which covers recovery, if the PUMP fails, try
it over and over.  (Neil, you might not remember this from when I did this
pitch to your user group, berceuse this was the notorious two hour pitch
where Ken Sadler cut me off after one hour!  I will never let him forget!)
Although I had personally never considered the dirty tape drive scenario, I
usually attempt to clean the tape drive if it has to be used.  Never the
less, failing DASD does not necessarily fail predictabily.  Clearly if the
disk head has driven itself into the rust, you're dead.  But there are some
occasions where electronic components in the DASD unit fail, and PUMP will
attempt to go in at a very low level and bypass these components.

(I was under the impression that we added DASD to DASD pump many releases
ago, is this no longer the case?)

Most attempts to use PUMP today fail, not because PUMP is less reliable,
but because the electronics are more reliable.  Notwithstanding this fact,
out shop has suffered three DASD failures in the last two months, and two
of the three were pumpable.  These failures occurred on an F25 where RAID-5
is not available.  Today, we hardly sell any systems without RAID-5, so
DASD failures have become a rarity.

Interesting note:  When you slip install V3R2, system revokes the *PUBLIC
*USE authority to the PWRDWNSYS command, which is a part of the system
trying to tighten up security.  Not a bad strategy, however this does break
many systems.  Consequently the V3R2 Memo to Users advises this change,
giving you the option to change it back, which is what we did.  When you
restore a V3R2 system from a DASD failure, the *PUBLIC authority is once
again revoked.  

I have reported this as a bug, and I was responded to that it's working as
designed.   I responded with the commend "bad design"!  My contention is
that restore should restore exactly what you saved, and not screw with your
data or security.  The Memo to Users is not what you use to recover a DASD
failure!

IBM is considering the problem.



Al Barsa, Jr. - Account for Midrange-L
Barsa Consulting, LLC.  
400 > 390

Phone:  914-251-9400
Fax:    914-251-9406





Private mail should be sent to barsa@ibm.net
+---
| This is the Midrange System Mailing List!
| To submit a new message, send your mail to "MIDRANGE-L@midrange.com".
| To unsubscribe from this list send email to MIDRANGE-L-UNSUB@midrange.com.
| Questions should be directed to the list owner/operator: david@midrange.com
+---