How to increase the ring buffers on a NSX Edge VM

Products

• VMware NSX

Issue/Introduction

• The following alarm, which is described in KB 330475, is being reported in the NSX Manager UI:

Title: Alarm for Edge NIC out of receive buffer / Edge NIC out of transmit buffer
Event ID: edge_health.edge_nic_out_of_receive_buffer / edge_health.edge_nic_out_of_transmit_buffer

• The plan is to increase the size of the ring buffer to resolve the alarm. The purpose of this KB is to provide the steps to correctly increase the buffer.

Environment

VMware NSX

Resolution

Please note a restart of the datapath process is needed to complete the increase of the ring buffer size.

The steps for increasing the ring size are the following:

1. Put one of the edge nodes into NSX maintenance mode, which will stop the data plane service. 
2. Change the rx/tx ring size to its desired size using the following command. Please note that the increases need to be in increments of 1024.
   
   set dataplane ring-size rx <new ring-size>
set dataplane ring-size tx < new ring-size>
   
   
3. Exit NSX maintenance mode on that Edge.
4. Check that the change has been applied correctly using the following command:
   
   get dataplane | find ring
   
   
5. If not then restart the Edge.
6. Repeat the same process on the other edges in the cluster.

Additional Information

NSX maintenance mode technical documentation.

Entering maintenance mode from the CLI KB311846