IBM iSeries Series Hardware Problem Analysis And Isolation page 27

v Look for dust on top of objects. Dust particles in the air cause poor electrical connections and
may cause disk unit failures.
v Smell for unusual odors in the air. Some gases can corrode electrical connections.
d. Any large vibration (caused by thunder, an earthquake, an explosion, or road construction) that
occurred in the area at the time of the failure.
Note: A failure that is caused by vibration is more probable if the iSeries server is on a raised
floor.
6. Ensure that all ground connections are tight. These items reduce the effects of electrical noise.
Check the ground connections by doing the following:
a. Look in the system installation information for instructions on how to connect the ground straps to
the frame bar and the correct hardware to use. The hardware is part of the ship group kit.
b. Ensure that a star washer is between the head of the screw and the ground strap.
c. Make sure the screw is tight. Check by holding the ground strap and attempting to turn it
counter-clockwise around the screw. If the screw loosens, tighten it so that it does not.
d. Measure the resistance between a conductive place on the frame to building ground or to earth
ground. The resistance must be 1.0 ohm or less.
7. All cables that leave each frame must be fastened to the bottom bar of each frame with a cable tie or
clamp.
Ensure that you pull the cable ties tight enough to fasten the cable to the frame bar tightly. A loose
cable can be accidentally pulled with enough force to unseat the logic card in the frame to which the
cable is attached. If the system is powered on, the logic card could be destroyed.
8. Where required, ensure that ferrite cores and their covers are installed on both ends of all IPI-3 signal
cables (DFCI cables) that leave the frame. The ferrite core can be installed up to 15 cm (6 inches)
from the connector; the recommended distance is 8.5 cm (3.4 inches).
The ferrite core is part 62X1146. The cover for the ferrite core is part 6495272.
Note: If the IPI-3 signal cables do not leave the frame, ensure that they do not hang below the
bottom of the frame. If they do, tie them up inside the frame.
9. Ensure that all workstation and communications cables meet IBM specifications:
v All connections are tight.
v Any twinaxial cables that are not attached to devices must be removed.
v The lengths and numbers of connections in the cables must be correct.
v Ensure that lightning protection is installed on any twinaxial cables that enter or leave the building.
10. Review the following:
a. Service entries. Determine what service actions were performed on the system (see the Problem
summary form).
b. Entries in the problem log (WRKPRB). Look for problems that were reported to the user.
c. Entries in the Product Activity Log. Look for a pattern:
v SRCs on multiple input/output processors (IOP) occurring at the same time
v SRCs that have a common "time of day" or "day of week" pattern
v Log is wrapping (hundreds of recent entries and no older entries)
Check the Product Activity Log sizes and increase them if they are smaller than recommended.
d. Entries in the history log (Display Log (DSPLOG)). Look for a change that matches the start of the
intermittent problems.
e. Your records and the service log. Ensure that the latest engineering changes are installed on the
system and on all system I/O devices.
11. Ensure that the hardware configuration is correct and that the model configuration rules have been
followed. Use the Display hardware configuration service function (under SST or DST) to check for
any missing or failed hardware.
Analyze hardware problems
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