Compaq ServerNet ServerNet II Installation Manual page 174

H-8 Compaq ServerNet II PCI Adapter and Switch Installation Guide
Suppose your local host is connected to Switch01, which is in turn connected to Switch02, as in
Figure H-8. Also suppose that the Routing test passes when Switch01 is the target but fails when
Switch02 is the target.
ServerNet
Cable A Cable B
Switch 01
Local Host
Computer
ServerNet
Switch 02
Figure H-8. Example of Local Host Connected to Switch02 via Switch01
Such a failure scenario could happen if there is a failure in either Switch01 (for example,
daughtercard B fails), or Cable B, or Switch02. See Figure H-9. There are currently no tools to
further isolate the failure online. Offline diagnostic tools might be able to better isolate the
failure.
Cable A
ServerNet
Switch
Cable B
ServerNet
Switch
Figure H-9. Which Part Should be Replaced
It is possible for a routing test to pass, even if a cable along the Route is incorrectly connected.
The IBC Scratch-Pad memory area in a node is available to any IBC client in an non-arbitrated
manner. If two people are running Diagnostics at the same time, they can cause the routing test
to fail even when the SAN has not failed. The symptom is that the data read is different from the
data written.