In an NSX-T environment, VRNI is reporting “high packet drops / more than 5%” warnings for NSX-T Logical Switch/Ports after applying DFW rules.

Products

• VMware Aria Operations for Networks
• VMware NSX Networking

Issue/Introduction

Symptoms:
The following Warning Events may be present on VRNI

• NSX-T Logical Port Received Packets are getting dropped
• Received packets are getting dropped on the NSX-T Logical Port and associated entities might get affected
• NSX-T Logical Port Transmitted Packets are getting dropped.
• Transmitted packets are getting dropped on the NSX-T Logical Port and associated entities might get affected

Environment

VMware NSX-T

Cause

• VRNI queries NSX-T via API for port statistics.
• NSX-T in turn gets this port statistic information from the ESXi host.
• Additionally, VROPs queries vCenter for port drop information which again is reported from the ESXi hosts.

Resolution

This is a known issue impacting VMware NSX-T Data Center and VMware NSX.

Note: In NSX-T environments configured with DFW or Service Insertion, false reports of packet drops will continue to be reported on all versions of ESXi.

Workaround:
To avoid VRNI System Events can be disabled/suppressed.
Please note if there is a real condition that is causing dropped packets, you will not be alerted.

1. In VRNI go to Settings -> Events -> System Events
2. Disable the following Events
3. NSX-T Logical Port Received Packets are getting dropped.
4. NSX-T Logical Port Transmitted Packets are getting dropped.