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Debugging and Diagnostics
This chapter describes debugging and diagnostics for the device.
Oine Diagnostics
The oine diagnostics test suite is useful for isolating faults and debugging hardware.
The diagnostics tests are grouped into three levels:
• Level 0 — Level 0 diagnostics check for the presence of various components and perform essential path verications. In addition,
Level 0 diagnostics verify the identication registers of the components on the board.
• Level 1 — A smaller set of diagnostic tests. Level 1 diagnostics perform status/self-test for all the components on the board and test
their registers for appropriate values. In addition, Level 1 diagnostics perform extensive tests on memory devices (for example, SDRAM,
ash, NVRAM, EEPROM) wherever possible.
• Level 2 — The full set of diagnostic tests. Level 2 diagnostics are used primarily for on-board loopback tests and more extensive
component diagnostics. Various components on the board are put into Loopback mode and test packets are transmitted through those
components. Level 2 diagnostics also perform snake tests using virtual local area network (VLAN) congurations.
Important Points to Remember
• You can only perform oine diagnostics on an oine standalone unit or oine member unit of a stack of three or more. You cannot
perform diagnostics on the management or standby unit in a stack of two or more; if you do, a message similar to this displays:
Running Diagnostics on master/standby unit is not allowed on stack.
• Diagnostics only test connectivity, not the entire data path.
• Diagnostic results are stored on the ash of the unit on which you performed the diagnostics.
• When oine diagnostics are complete, the unit or stack member reboots automatically.
Running Oine Diagnostics
To run oine diagnostics, use the following commands.
For more information, refer to the examples following the steps.
1 Place the unit in the oine state.
EXEC Privilege mode
offline stack-unit stack-unit-number
You cannot enter this command on a MASTER or Standby stack unit.
NOTE
: The system reboots when the oine diagnostics complete. This is an automatic process. The following warning
message appears when you implement the offline stack-unit command: Warning - Diagnostic
execution will cause stack-unit to reboot after completion of diags. Proceed with
Offline-Diags [confirm yes/no]:y
After the system goes oine, you must reload or run the online stack-unit stack-unit-number command for the normal operation.
2 Conrm the oine status.
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