On-Line Track Reservation (Flaw) - Control Data Corporation CYBER 170 Series Operator's Manual

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K.RU=4,OP=A,CH=02
Adds unit 4 to EST ordinal 5 with channel
2 assigned.
K.GO
Initiates processing.
EST ordinal 5 can now be switched with EST
ordinal 10 as shown previously.
EXAMPLE 3'
Assume the following hardware configuration of 844 drives
is being used.
EST Ordinal Unit
ChanneI(s)
Status
1 0 1
2
1 1
3 2 1 Removable
4 0 2
5 1
2
6 2 2
Unit 1 on ,channel 2 (defined by FST ordinal 5) begins' to
fail. There is no removable device assigned to channel 2,
no spare unit on channel 2 and no unit shared with the
controller
on
channell. Therefore, reconfiguration is not
possible. It is recommended that at least one removable
device exist for every controller/channel path.
ON-LINE TRACK RESERVATION (FLAW)
The FLAW utility reserves (flaws) tracks on any mass
storage device during normal system operation. Each entry
identifies an area of mass storage that is unusable (flawed
area) and prevents the system from accessing it. Since 881
and 883 disk packs normally contain flaw information in the
utility sector, the FLAW utility should be used on an 881 or
883 only to specify additional areas not currently in the
utility sector. Obtain flaw addresses from the customer
engineer or the system analyst.
Flawing tracks on mass storage devices is accomplished
using the K display (figure 6-3). Note that all console entry
is performed under DSD control. The sequence is as
follows:
1.
2.
6-6
Call FLAW utility by typing
X.FLAW.
Bring K display to left console screen by typing
K,n.
n
Control point number requesting
the K display (m essage
REQUEST*K*DISPLA Y appears at
control point n on B display).
3. Specify mass storage device on which tracks are
to be flawed. Enter
K.EQ=xx.
xx EST ordinal of the mass storage
device.
4. Enter flaws. A maximum of 20 octal flaw entries
is allowed for each call to the FLAW utility. In
addition, there are three types of flaw entries
that may be specified. The general format for K
display entry is
K.xtk=ta.
xtk Specifies type of flaw entry. '
ta
STK
TTK
Sets track reservation table
(TRT) entry for the specified
logical track to indicate that
track is unavailable for use.
Toggles track reservation
table entry for speCified
physical ECS track. If TRT
indicates that track is
currently unavailable, track
is made available and vice
versa.
RTK
Sets the track reservation
table entry for the specified
physical block (track) address
in ECS to indicate that the
block is unavailable for use.
Specifies track address to be
reserved.
tttt
Logical track address' for 844
disk, 885 disk, or extended
core storage. (Use with STK.)
40008-71378 for 844-21 disk
(DI/DK)
4000r7147~ for 844-41/44
disk DJ/DL
40008-72228 for 885 disk
(DM/DQ)
40008-76208 for 2048K ECS
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(DE/DP)
60435600 L