RISCSYSTEM- UPGRADES R24
ITEM: RTA000053975
QUESTION:
Can you please clarify three points on upgrades to R24 from 970 and
98B machines:
1. Please elaborate on the benefits and uses of the 6005 feature. We
are considering, instead of an external rack with disk for
high availability, having 9333 disk in each of the two machines
with their own power supply, separate from the cpu and other
devices. We know this is not the optimal HA configuration, but
can it/will it work?
2. The R24 has an optional remote IPL port. Can this be installed
on UPGRADES from 9XX systems to the R24? Configurator does not
give option -- it is technical reason?
3. Please clarify if feature 4001 is needed in the following scenario:
We have to R24s with external 9333/011 disks, two 6212--High Perf
subsystem adapters in each of the R24s, and two serial link 3 meter
cables on each 9333/011. We want both R24s to access the 9333 disk.
Do we also need 4001? If not, can you explain when we may need
this feature?
Thanksą
---------- ---------- ---------- --------- ---------- ----------
A: I will answer your questions in the order asked:
1. Feature 6005 consists of an optional set of power control cables
for the rack. This feature permits power to the IBM tape and disk
devices installed in the 900 series system to be controlled from
either of two CPUs for high-availability configurations with dual
systems.
Many devices within the racks (e.g. - 9333/010, 9334/010) have Power
Control Interface ports (PCI's) on the back. The Power Control
Cables, which are long, grey cables that have what look like
connections for a RISC/6000 mouse port, are what connect the PCI's in
a daisy-chain fashion.
As shipped, all devices that have the PCI's will have the PCC
cables daisy-chained to/through them. The CPU within the rack
sends a signal through these cables to indicate that the CPU is
powered-on, so that the device will power-on. Whenever the CPU
stops sending this signal, the devices know that the CPU is no
longer powered-on, and they will power-off (by default). When
someone issues a "shutdown" to the R24 CPU, it will quit sending
the signal, and the individual drawers will know to power-off.
This is a nice feature, in that a simple "shutdown" will power-off
the entire rack, but it can create problems in a highly available
environment.
In a highly available environment, people tend to cross connect
the 9333 drawers between the CPU racks. This is fine, except
that if one of the racks is powered-off or "shutdown", the 9333
will power down also. Obviously, the data on the disks is no
longer accessible by the other CPU, so this can cause many
problems.
There are two solutions to this problem:
A) Re-wire the Power Control Cables to NOT go through the 9333's
and make sure the switch below the associated 9333's power
cable on the Power Distribution Unit is in the "1" position.
The "1" on the Power Distribution Unit means that power will
always be supplied to the attached drawer, regardless of CPU
status.
B) Daisy-chain some Power Control Cables from the other CPU to the
auxiliary ports on the 9333/010. By doing this, both CPU's can
send a signal to the 9333. The 9333 will remain powered-on as
long as EITHER or both of the attached CPU's are powered-on.
This will work equally as well for 9333's that are installed in
7202 expansion racks. This will require the "Dual Power Control
Feature" (feature code 6005), which are the necessary cables.
Please contact your CE for the cabling setup.
You will, of course, have a single point of failure at the Power
Control Unit on each upgraded R24 system (99J/99K). A new rack
system would allow for the ellimination of this, BUT... (YES) this
this configuration will work.
2. No, this is only available with initial plant orders and not with
MES/Upgrade options. You can submit an RPQ to see if they will
allow this in the future. We at ASKQ are not aware of the technical
reason on why this is not orderable, but the Configurator is correct
here.
3. Feature 4001 will not be needed unless you plan on connecting
more than two systems to the 9333. The 9333 already is equipped with
two connectors to attach to up to two systems at once. Since your
configuration includes just the 99J and 99K, you will be fine
without it.
Thank you.
---------- ---------- ---------- --------- ---------- ----------
This item was created from library item Q677711 FFRML
Additional search words:
AUTO AUTOMATIC DEC94 FFRML HARDWARE IX OZIBM OZNEW RISCSYSTEM
RISCSYSU R24 SYS SYSTEM UNIT UPGRADE UPGRADES
WWQA: ITEM: RTA000053975 ITEM: RTA000053975
Dated: 10/1996 Category: RISCSYSU
This HTML file was generated 99/06/24~12:43:21
Comments or suggestions?
Contact us