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ELS100-16TX Diagnostics and Troubleshooting
Note: If a critical component fails diagnostics, the CPU LED will turn off and the ELS100-16TX 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 ELS100-16TX include:
•ROM checksum test
•Instruction/Data memory test
•FLASH checksum test
•NVRAM checksum test
5.1.3 Software Checksum Comparison
When the ELS100-16TX 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 ELS100-16TX will automatically use its backup version of software. A backup version of software is always stored in non-volatile memory.
The operational parameters of the ELS100-16TX software are also protected by a checksum comparison. When the ELS100-16TX reboots, if the operational parameters of the ELS100-16TX fail a checksum test due to a power failure in the midst of a previous update, the ELS100-16TX automatically uses its backup version of the parameters.
Note: A backup version of the operational parameters is always stored in non-volatile memory before any update is attempted.