System Troubleshooting and Diagnostics
5.7 Using Loopback Tests to Isolate Failures
4. Power up the system. Note that the red Fault indicator on the ISE front
panels will remain lit. This is normal when the bus node ID plugs have
been removed.
5. Run test 56. When tests have successfully completed, the console prompt is
displayed.
Note
The sequence of the bus id is
from
and
to
. The following example reads:
run test 56
from
bus 0
to
bus 1.
>>>T 56 0 1
>>>
Note
It is recommended that you run Test 56 both ways. Using the above
example, you should also run test 56 from bus 1 to bus 0.
This loopback test is useful for isolating DSSI problems. A list of FRUs in
order of probability follows:
1. The external BC21M–09 cable
2. The Vterm dual regulator module (PN 54–20404–01)
3. The internal cable that connects DSSI Bus 0 from the backplane to the
edge of the enclosure (PN 17–02502–01)
4. The internal cable that connects the CPU to the H3604 (PN 17–02353–01)
5. The 2.0 A Pico fuse (F3) on the H3604 (PN 12–10929–06)
6. The KA681/KA691/KA692/KA694 module
Test 58 is a SHAC and ISE reset and can be used to verify that ISEs can be
accessed on the DSSI storage bus. Test 58 causes data packets to be passed
between the ISEs and the adapters, verifying that the ISEs are accessible.
Enter T 58 and specify DSSI bus (0 or 1) and the DSSI node ID of the ISE to
be tested.
>>>T 58 0 5
In the example above, Bus 0 node 5 was tested. (Each ISE has to be tested
separately.)
5–74 System Troubleshooting and Diagnostics
