IBM B-Series, Maintenance Information

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Error Log Analysis Procedure
The Error Log Analysis Procedure is designed to assist the service representative in isolation of
intermittent failures, or chronic problems that seldom happen but occur often enough to cause a concern.
We will use the error log to demonstrate how one might look for possible leads on which FRUs to replace
in such a case. The example we will use is not a real example, but is intended for demonstration only.
Figure 271 on page PROC-50 shows a blank Error Log Analysis Work Sheet that you may make copies
of and use to write down FIDs with the following procedure. Figure 274 on page PROC-52 shows the
same Error Log Analysis Work Sheet with a sample extraction from the 3570 error log.
Following is an example of how you might gather and analyse error log data. The 10 entries below
represent a summary of what you might find in the 3570 error log:
Entry 1 FID 98
Entry 2 FID 9E
Entry 3 FID 9F
Entry 4 FID C5
Entry 5 FID BF
Entry 6 FID CA
Entry 7 FID C5
Entry 8 FID A8
Entry 9 FID 9F
Entry 1 FID 98
In a real situation, you would extract the error log FID data and fill out the blank Error Log Analysis Work
Sheet using the following procedure. Our example has all the data recorded for your convenience:
Note: When you have concluded reading out the error log, reset the device by power off then on.
1. Take the FID from the most recent error log entry and put it in the first column labeled Error Log FID
Entries, row one, (FID 98 in our example). Continue listing FIDs that you find in the error log until you
get to the last one you choose to use in the analysis.
Note: If the time stamp shows a long duration between one entry and the next, you may want to
ignore any of the older entries for the purpose of this exercise.
2. Refer to “FID Entry Point” on page START-12, under the table column Reported FID and locate the
first FID that you extracted from the error log and wrote down in the left column of your work sheet. To
the right of that entry on the work sheet, under START Section FRU Names (FID Numbers), list from
left to right, in order of listed probability, the FRU that is called out under the column FRU Name in the
START pages. To save space, use the FID number that is associated with each FRU. A cross
reference of FRU Names to FID Numbers may be found in Figure 272 on page PROC-51, and a
cross reference of Fid Numbers to FRU Names may be found in Figure 273 on page PROC-51. In
the top line of our example, we listed FIDs 9A, A3, 97 and A5.
3. Repeat the previous step for each FID you wrote down on the work sheet. When all has been written
down, continue with the next step.
4. Look first in the left two or three columns of your Error Log Analysis Work Sheet, under the START
Section FRU Names (FID Numbers) and draw a circle around the FID that appears most often (in
our example we circled FID 9A five times).
5. Next, look in the left two or three columns and draw a square around the next FID that occurs the
most often (in our example we drew a square around FID BC, four times).
6. Now, look at the overall entries, and draw a diamond around any FID that occurs most often (in our
example we drew a triangle around FID 97.)
PROC-48
IBM 3570 MI