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ELS10-26 Diagnostics and Troubleshooting
5.After several more seconds, the CPU LED will stay on, indicating that the power-up diagnostics sequence is complete.
In addition, the Port Link LEDs will turn on for those ports with good links and the Segment Status LEDs will turn on (or flash) when the selected status condition is present.
Note: If a critical component fails diagnostics, the CPU LED will turn off and the ELS10-26 will attempt to reboot. If the CPU LED does not stay on, contact Cabletron Systems Global Call Center. Refer to Section 1.2.
5.1.2 Specific Power-up Tests
The power-up diagnostic tests performed on the ELS10-26 include:
•ROM checksum test
•Instruction/Data memory test
•FLASH checksum test
•NVRAM checksum test
•Ethernet data loopback test
5.1.3 Software Checksum Comparison
When the ELS10-26 reboots, its operational software is verified by a checksum comparison before it is loaded. If the software fails the checksum test due to an interrupted new software distribution procedure, the ELS10-26 will automatically use its backup version of software. A backup version of software is always stored in non- volatile memory.