Installation guide

Installation Troubleshooting
9.1 Troubleshooting the Storage Enclosure
Table 9–1 (Cont.) Troubleshooting Chart
Symptom(s) Probable Cause(s) Corrective Action(s)
In a DSSI VAXcluster
installation, one or
more of the following
symptoms are observed:
-unexplained virtual
circuit (VC) closures
-unexplained VMS
crashes
-performance degrada-
tion
1. Excessive ground
offset voltage
between DSSI
VAXcluster
cabinets.
1. Refer to Chapter 2.
Measure ground offset
voltage between cabinets.
Correct faults in power
distribution system.
Install cabinet grounding
wire between all cabinets
sharing DSSI buses.
2. Loose or missing
DSSI terminators.
2. Tighten or replace DSSI
terminators.
3. Low terminator
power voltage.
3. Replace fuses.
4. Bus length too long. 4. Shorten bus.
5. Non DEC devices
on bus.
5. Replace with DEC devices.
6. Terminated mid-
bus adapters
6. Remove terminators from
mid-bus adapters.
9–6 Installation Troubleshooting