3V0-25.25: Advanced VMware Cloud Foundation 9.0 Networking

By Broadcom · Question Mode

QuestionQ4

VerifiedUnknown / not found in official Broadcom sources

An administrator is investigating why workloads in NSX are unable to reach the external network 10.100.0.0/16.

The Tier-0 Gateway operates in Active/Active mode and has this configuration:

  • Uplink-1 (VLAN 100): 192.168.100.0/24 → router R1 at 192.168.100.1
  • Uplink-2 (VLAN 101): 192.168.101.0/24 → router R2 at 192.168.101.1

A static route for 10.100.0.0/16 was configured with both next hops (192.168.100.1 and 192.168.101.1).

The Scope for this route is set to Uplink-1.

Symptoms:

  • Virtual Machines (VMs) cannot reach 10.100.0.0/16.
  • A traceroute from the VM ends at the Tier-0 gateway with "Destination Net Unreachable."
  • Pings from the Edge nodes to both 192.168.100.1 and 192.168.101.1 succeed.

What accounts for the NSX workloads being unable to reach the external network?

Explanation

A static-route next hop must be scoped to the interface or segment that can reach it. 192.168.101.1 belongs to VLAN 101 on Uplink-2, but the route is scoped only to Uplink-1. The two next hops must be associated with their respective uplinks (or configured as appropriate separate scoped routes), so limiting the scope to Uplink-1 leaves the VLAN 101 next hop incorrectly scoped.

Learn more

Community Discussion

No comments yet. Be the first to start the discussion!