NSX-T alarm generated: Flow cache disabled

Products

• VMware NSX

Issue/Introduction

• Flow cache is a feature in the data plane which helps to speed up packet processing, thus improving Edge performance. If it is disabled, this will reduce the number of packets processed per second.
• There is a new alarm introduced in NSX 4.1.1.1 which will check if flow cache is enabled or not on the Edge nodes. If it is not enabled on the edge nodes, it will alert and indicate which edge nodes it is disabled on.

Environment

VMware NSX

Cause

• In the past there may have been situations where flow cache was disabled for troubleshooting purposes and has remained disabled.
• If there is no longer any need to have flow cache disabled, it can be re-enabled.

Resolution

Please enable flow cache on the Edge node to increase performance:

• As admin user on the Edge CLI, confirm flow cache is disabled:

#get dataplane flow-cache config

Enabled            : false
Mega_hard_timeout_ms: 4966
Mega_size          : 262144
Mega_soft_timeout_ms: 4898
Micro_size         : 262144

• To enable flow cache reference this KB: NSX-T Edge Flow Cache.