2.1 CPU Troubleshooting
2.1.1 CPU Usage Is High
Common Causes
CPU usage is the percentage of the time during which the CPU executes codes to the total time
period. CPU usage is an important index to evaluate device performance.
To view CPU usage, run the
display cpu-usage
command. If you see that CPU usage exceeds
70%, CPU usage is high. A high CPU usage will cause service faults, for example, BGP route
flapping, frequent VRRP active/standby switchovers, and even failed device login.
High system CPU usage occurs when CPU usage of some tasks remains high. This fault is
commonly caused by one of the following:
l
A large number of packets are sent to the CPU when loops or DoS packet attacks occur.
l
STP flapping frequently occurs and a large number of TC packets are received, causing the
device to frequently delete MAC address entries and ARP entries.
l
The device generates a large number of logs, consuming a lot of CPU resources.
Troubleshooting Flowchart
shows the troubleshooting flowchart.
Huawei AR2200-S Series Enterprise Routers
Troubleshooting
2 System
Issue 01 (2012-01-06)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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