OpenVMS Cluster Systems - OpenVMS Systems - HP

Cluster Troubleshooting
C.10 Diagnosing Port Failures
2. The configuration poller makes entries in the error log whenever it detects
a change in the state of a circuit. Note, however, that it is possible two
changed-to-failed-state messages can be entered in the log without an
intervening changed-to-succeeded-state message. Such a series of entries
means that the circuit state continues to be faulty.
C.10.6 Diagnosing CI Cabling Problems
The following paragraphs discuss various incorrect CI cabling configurations and
the entries made in the error log when these configurations exist. Figure C–1
shows a two-computer configuration with all cables correctly connected.
Figure C–2 shows a CI cluster with a pair of crossed cables.
Figure C–1 Correctly Connected Two-Computer CI Cluster
Local
CI
Port
TA
TB
RA
RB
Figure C–2 Crossed CI Cable Pair
Local
CI
Port
TA
TB
RA
RB
X
Star
Coupler
Star
Coupler
RA
RB
TA
TB
RA
RB
TA
TB
Remote
CI
Port
ZK−1924−GE
Remote
CI
Port
ZK−1925−GE
If a pair of transmitting cables or a pair of receiving cables is crossed, a message
sent on TA is received on RB, and a message sent on TB is received on RA. This
is a hardware error condition from which the port cannot recover. An entry is
made in the error log indicating that a single pair of crossed cables exists. The
entry contains the following lines:
DATA CABLE(S) CHANGE OF STATE
PATH 1. LOOPBACK HAS GONE FROM GOOD TO BAD
If this situation exists, you can correct it by reconnecting the cables properly. The
cables could be misconnected in several places. The coaxial cables that connect
the port boards to the bulkhead cable connectors can be crossed, or the cables can
be misconnected to the bulkhead or the star coupler.
Cluster Troubleshooting C–21