Description

This article explains the meaning of the Syslog error 'kernel: %KERN-2-MCA: CPU 3 COR (7) OVER RD channel ?? memory error' .

Symptoms

Verify to which RE the errors are being logged [if chassis has dual-REs]. In the example below, the issue was seen in RE1

Routing engine 1 continuously logs the following messages:

Router-re1 kernel: %KERN-2-MCA: Bank 8, Status 0xcc0000800001009f
Router-re1 kernel: %KERN-2-MCA: Global Cap 0x0000000000001c09, Status 0x0000000000000000
Router-re1 kernel: %KERN-2-MCA: Vendor "GenuineIntel", ID 0x106e4, APIC ID 4
Router-re1 kernel: %KERN-2-MCA: CPU 2 COR (2) OVER RD channel ?? memory error
Router-re1 kernel: %KERN-2-MCA: Address 0x4c20e9b80
Router-re1 kernel: %KERN-2-MCA: Misc 0xaa404000000400c1
Router-re1 kernel: %KERN-2-MCA: Bank 8, Status 0xcc0001c00001009f

Solution

MCA (Machine Check Architecture) is an Intel mechanism in which the CPU reports errors to the OS, Intel's processors, as well as the Itanium architecture, implement a machine check architecture that provides a mechanism for detecting and reporting hardware errors. This specific error is for memory errors reported on the Routing Engine of the device. 

If this log only appears once, it is most likely that this is a transient issue with RE1 memory. In that case, reboot the RE1 and monitor. 

Ideally, in case of a transient issue, a reboot will re-initiate all functions and processes running on the RE1 and the RE1 stabilizes.

If the log continues to appear after a reboot, it is suggested to replace the RE1. If the log still exists even after replacement, contact your  JTAC Representative for additional assistance.

Modification History

3/14/2024