Bare Metal Servers Unable to Establish Network Connectivity via Tier-0 Gateway

Products

• VMware NSX

Issue/Introduction

• Multiple bare metal servers are unable to establish network connectivity within the NSX-T environment.
• Connectivity loss is verified between the bare metal servers and the Tier-0 (T0) gateway.
• Analysis of routing tables and log bundles indicates traffic fails to reach the destination segment.
• Traceflow or logs may indicate "Dropped for no route found" at the Tier-0 gateway.

Environment

Vmware NSX 

Cause

The issue is caused by a configuration omission on the Tier-0 gateway. Specifically, the necessary Next Hop route for the bare metal server segment is not defined. In NSX-T architecture, Tier-0 gateways require explicit routing instructions (via static routes or dynamic protocols like BGP) to forward traffic to external or bare metal segments. Without a valid Next Hop entry, the gateway cannot determine the egress path for server traffic.

Resolution

To restore North/South traffic flow for bare metal servers, the routing configuration on the Tier-0 Gateway must be updated.

Step 1: Update the Static Route

1. Log in to the NSX Manager with admin privileges.
2. Navigate to Networking > Tier-0 Gateways.
3. Click the menu icon (three dots) for the target gateway and select Edit.
4. Expand Routing and click Set next to Static Routes.
5. Click Add Static Route (or edit the existing route for the bare metal segment).
6. Enter the Name and Network (in CIDR format).
7. Click Set Next Hops.
   • Note: If the Next Hops window is greyed out with a banner stating "To edit below content, click EDIT", ensure you have clicked EDIT on the parent Tier-0 Gateway configuration first.
8. Add the correct Next Hop IP address  and save the configuration.

Step 2: Enable Route Redistribution

1. While still editing the Tier-0 Gateway, expand the Route Redistribution field.
2. Click the number next to the Route Re-distribution item.
3. Ensure Connected Interfaces & Segments is enabled.
4. Save all changes in the pop-up windows and on the main Tier-0 Gateway editing page.