Error 11019: Tier-0 Static Route Configuration Fails in Active-Active Edge Cluster: VMware NSX

Products

• VMware NSX

Issue/Introduction

• Introduction: When configuring a Tier-0 Gateway in an Active-Active high availability (HA) mode with multiple Edge nodes and dual uplinks, static route definitions that include an explicit interface Scope may fail with Error 11019. This error indicates that the configuration has exceeded the management plane limit for equal-cost next hops.

  Symptoms

  • Configuring a Tier-0 Gateway static route fails with: Error: [error_code=11019, module_name=ROUTING, error_message='[Routing] Max 8 equal cost next hops are allowed. Network 0.0.0.0/0 has X next hops with Administrative distance 1.']
    
    
  • 'X' represents the total number of next-hops across all Edge nodes (e.g., 16 paths in an 8-node, dual-uplink cluster).

Environment

• VMware NSX 4.x

Cause

• When a specific interface is selected in the Scope field, the NSX Management Plane validates all entries globally as a single route. In clusters with multiple Edge nodes, the aggregate number of uplink next-hops often exceeds the 8-path ECMP limit, triggering the validation error.

Resolution

Resolution To resolve this issue and align with VMware design best practices for multi-node Active-Active clusters:

1. Navigate to the Tier-0 Gateway static route configuration.
2. For the impacted route (e.g., 0.0.0.0/0), ensure the Scope (Interface) field is left blank/unset.
3. Define the Next Hop IP addresses for all uplinks across the Edge cluster.
4. Save the configuration.

 

Routing Behavior Implications:

• Scoped Routes: Hard-pins traffic to specific interfaces. This is used primarily if identical next-hop IPs exist on different interfaces/VRFs.
• Unscoped Routes (Recommended): Dynamically resolves next-hops against local connected subnets. This provides cleaner failover and prevents configuration caps in multi-node clusters by allowing NSX to execute two-tier ECMP (DR spreads across Edge nodes; each Edge node spreads across local uplinks).

Additional Information

• For more details, refer to Understanding ECMP Routing.
• For instructions on downloading Broadcom products, see Download Broadcom Products and Software.
• To contact support, see Contact Broadcom Support.