TCP packets were not reaching LB VIP on tier-1 GW of edge node from external networks

Products

• VMware NSX

Issue/Introduction

TCP packets from external VM were not reaching client VM via VIP configured on tier-1 GW of Edge nodes. 

Environment

3.2.3

Cause

It was observed that packets were reaching from uplinks to tier-0 but not forwarded to tier1 routers, so that packets were getting dropped in the tier-0 interface itself.

Check the interface stats by logging to Edge node and entering the corresponding Tier-0 SR VRF using below commands 

>> ssh <Edge Management IP>

>> get logical-routers (Get the VRF ID of corresponding tier-0 router)

>> get interface-stats 

check if the Rx or Tx drops are incrementing for the corresponding interface as traffic traverses the edge node 

Type below to check the forwarding and routing and check if any default static route is configured for this tier-0 VRF (despite configuring BGP to reach uplink routers)

>> get forwarding 

 

 

Resolution

Check if there are any default static route configured and check if the routes can be removed (via GUI) to forward traffic to tier-1 gateway