Insights about routes with an invalid next hop

This page describes the Network Analyzer insights for routes with an invalid next hop. For information about all the insight types, see Insight groups and types.

View insights in the Recommender API

To view these insights in the gcloud CLI or the Recommender API, use the following insight type:

  • google.networkanalyzer.vpcnetwork.connectivityInsight

You need the following permissions:

  • recommender.networkAnalyzerConnectivityInsights.list
  • recommender.networkAnalyzerConnectivityInsights.get

For more information about using the Recommender API for Network Analyzer insights, see Use the Recommender CLI and API.

VM doesn't have a network interface in the route's network

This insight indicates that the next hop is invalid because the VM instance doesn't have a network interface (vNIC) in the route's VPC network.

The insight includes the following information: the route name, network name, and the next hop.

For more information, see Considerations for next hop instances.

Recommendations

Attach a vNIC to the VM instance in the route's VPC network.

Next hop IP address isn't the VM's primary IP address

This insight indicates that the route's next hop is a non-primary IP address of a VM.

The insight includes the following information: the route name, network name, and the next hop.

For more information, see Considerations for next hop instances.

Recommendations

Delete the invalid route and add a new route using the VM's primary IP address.

IP address forwarding is disabled for the VM instance

This insight indicates that the VM as the next hop of the route cannot forward packets.

The insight includes the following information: the route name, network name, and the next hop.

For more information about IP address forwarding, see Enable IP forwarding for instances.

Recommendations

Enable the canIpForward property of the VM instance by using the gcloud CLI. For more information about using the CLI or API, see Updating instance properties. Export the existing instance properties, modify the canIpForward field, and then upload the updated property file.

The canIpForward field in an exported instance property file appears as follows:

canIpForward: false

If it is true, the instance has canIpForward already enabled. If canIpForward is false, change the value to true, and update the instance properties by using the modified file. To change this property, set the most-disruptive-allowed-action flag value to REFRESH because it does not require an instance restart.

For more information, see Update instance properties.

VM is stopped

This insight indicates that the next hop of the route is invalid because the VM instance has been stopped.

The insight includes the following information: the route name, network name, and the next hop.

For more information, see Considerations for next hop instances.

Recommendations

Restart the VM instance.

VM is deleted

This insight indicates that the next hop of the route is invalid because the VM instance has been deleted.

The insight includes the following information: the route name, network name, and the next hop.

For more information, see Considerations for next hop instances.

Recommendations

Recover the deleted VM. If you don't need this route, you can delete it.

Internal load balancer is misconfigured

This insight indicates that the next hop in the route is invalid because the internal load balancer used as the next hop of the route is deleted.

The insight includes the following information: the route name, network name, and the next hop.

For more information, see Considerations common to instance and internal passthrough Network Load Balancer next hops.

Recommendations

Recreate the deleted load balancer. If you don't need this route, you can delete it.

Virtual IP address isn't assigned for the internal load balancer backend

This insight indicates that the next hop IP address isn't associated with a forwarding rule.

The insight includes the following information: the route name, network name, and the next hop.

For more information, see Considerations common to instance and internal passthrough Network Load Balancer next hops.

Recommendations

To use the route, configure an internal passthrough Network Load Balancer with the IP address of the next hop. If you don't need this route, you can delete it.

Forwarding rule IP address mismatch

This insight indicates that the route's next hop is invalid because the IP address that it targets isn't associated with the specified next hop forwarding rule.

The insight includes the following information: the route name, network name, and the next hop.

For more information, see Considerations for internal passthrough Network Load Balancer next hops.

Recommendations

Delete the invalid route and add a new route using the forwarding rule's IP address.

Invalid forwarding rule type

This insight indicates that the route is invalid because the specified next hop forwarding rule isn't associated with an internal passthrough Network Load Balancer or uses the L3_DEFAULT protocol.

The insight includes the following information: the route name, network name, and the next hop.

For more information, see Considerations for internal passthrough Network Load Balancer next hops.

Recommendations

Review your routes. If you don't need this route, you can delete it.

Cloud VPN tunnel isn't in established state

This insight shows that the route drops packets because the next hop is an unestablished Cloud VPN tunnel.

The insight includes the following information: the route name, network name, and the next hop.

For more information, see Interpret tunnel status messages.

Recommendations

Review the configuration of the Cloud VPN tunnel.

Cloud VPN tunnel is deleted

This insight shows that the route drops packets because its next hop is a Cloud VPN tunnel that has been deleted.

The insight includes the following information: the route name, network name, and the next hop.

For more information, see Considerations for Classic VPN tunnel next hops.

Recommendations

Recover the deleted Cloud VPN tunnel. If you don't need this route, you can delete it.

Next hop IP address isn't assigned to any endpoint

This insight shows that the route drops packets because the next hop is an IP address that isn't assigned to any endpoint in the route's network.

The insight includes the following information: the route name, network name, and the next hop.

Recommendations

Review your routes. If you don't need this route, you can delete it.