This article explains more about a hardware error on the log message concerning(MPC7E 3D 40XGE) , FPC or RE aswell in the kernel vmhost log sessions.

> show log messages.5.gz | match HARD

fpc8 kern.info kernel:mce: [Hardware Error]: Machine check events logged

fpc8 kern.emerg kernel:mce: [Hardware Error]: CPU 1: Machine Check: 0 Bank 5: 9400004000900090

fpc8 kern.emerg kernel:mce: [Hardware Error]: TSC 0 ADDR 26ce3aa80

fpc8 kern.emerg kernel:mce: [Hardware Error]: PROCESSOR 0:406d8 TIME 1701349350 SOCKET 0 APIC 2 microcode 128

+++++++++++vmhost-kernel level logs++++++++++++++

2024-07-08T02:24:25.266526+05:30 Router_A kernel: mce: [Hardware Error]: Machine check events logged

On Linux, the kernel writes messages about MCEs to the kernel message log and the system console. When the MCEs are not fatal, they will also typically be copied to the system log and/or systemd journal. For some systems, ECC and other correctable errors may be reported through MCE facilities.

Types of MCE errors :

• System bus errors: (error communicating between the processor and the motherboard).
• Memory errors: parity checking detects when a memory error has occurred. Error correction code (ECC) can correct limited memory errors so that processing can continue.
• CPU cache errors in the processor.

If they don't repeat they are transient and can be ignored.

If persistent that it is a HW problem particular FRU needs RMA.