A set of SG9280E through Console login the main control MSU, it will prompt ceaselessly: “Board in slot 8 offline!”, after a few minutes it prompts: “Board in slot 8 online!”.
Through Console login the backup MSU, the MSU state is normal, eliminate the first reason.
Try to restart the backup and main MSU, fault is still.
Checking the CPU utilization ratio of the main MSU is up to 90%, but the SIG is still in offline state, in theory it should not have so high CPU utilization ratio. Check the CPU utilization ratio of backup MSU, it exists the same problem.
Detailed checking found the flow statistic of MSU’s LAN-1 port increased rapidly, from the sort can see it mainly is broadcast message. So we doubt that the network exists loop which caused the broadcast storm.
Try to interrupt the connection line of the MSU’s LAN-1 interface, the CPU utilization ratio of MSU decreased rapidly. And at this time there is no the hint that the card is off-line, problem has been solved.
Slot8 plugs the backup MSU main control switch unit.
The possible reasons are as follows:
1, the backup MSU hardware fault, it is in unstable state
2, the communication between the main MSU and the backup MSU is abnormal, which leads to heartbeat detection abnormal.
3, software problem.