Congestion mitigation

Try the following actions to mitigate congestion.

Note

For further details about congestion control, see the Extreme SLX-OS QoS and Traffic Management Configuration Guide.

• Increase bottleneck bandwidth.
  • Add more links to the LAG and ECMP paths.
  • Use higher-speed interfaces.
• Implement flow control on the bottleneck and on neighboring devices.
  

  Note

  Flow control can increase the number of discards.
• Implement QoS congestion management schemes.
  • Classify, mark, and prioritize critical traffic.
  • Modify scheduling schemes.
  • Random Early Detection (RED)

For the flow control solution, enable flow control either on the ports receiving the traffic from end-devices (servers or personal computers) and the connected end-device itself, or enable flow control on the port-channel as shown in the following example.

device(conf-if-eth-0/24)# interface port-channel 100
device(config-Port-channel-100)# qos flowcontrol tx on rx on

Once flow control is enabled, enter the show interface stats brief command again and check the output. It should no longer be reporting packet drops. If the packet drops continue or the ingress rate is considerably lower than expected, contact your device support provider for further investigation.

Note

For TCP sessions with low latency, expect small discards.