Configure static routes

This page shows you how to configure static routes for Network Connectivity Center. If you aren't familiar with static routes, see the Static routes overview.

When you select the IP address of the internal passthrough Network Load Balancer, its forwarding rule's --load-balancing-scheme must be INTERNAL. You can use any --destination-range that meets the following criteria:

The --destination-range doesn't exactly match the destination of a subnet route.
The --destination-range doesn't have a longer subnet mask than the destination of a subnet route.

For more information about destination range requirements, see destination IP address range.

Create static routes

You can create static routes for Network Connectivity Center spokes by using the gcloud compute routes create command. The following example shows you how to create a static route for a Network Connectivity Center spoke:

  gcloud compute routes create ROUTE_NAME \
      --network=HOME_VPC \
      --destination=DESTINATION_RANGE \
      --priority=PRIORITY \
      --next-hop-ilb=FORWARDING_RULE

Replace the following:

ROUTE_NAME: the name of the route.
HOME_VPC: the name of the VPC network that contains the route.
DESTINATION_RANGE: the destination IPv4 addresses to which this route applies. The broadest possible destination is 0.0.0.0/0.
PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority). For more information about route priority, see Routing order.
FORWARDING_RULE: IP address of a forwarding rule for an internal passthrough Network Load Balancer.

The following sections demonstrate two use cases, highlighting the differences in how you create static routes for mesh and star topologies.

Create static routes in a mesh topology

For this example, assume that you have two spoke VPCs, vpc-1 and vpc-2, which are connected to the same Network Connectivity Center hub. Suppose that you also have a transit VPC transit that is connected to vpc-2 through a network virtual appliance (NVA). You want to reach the transit VPC from the vpc-1 and vpc-2 spokes, so you configure static routes using the following steps:

First, create a static route in spoke vpc-1 with the transit VPC's IP address as the destination, and vpc-2's internal passthrough Network Load Balancer IP address as the next hop:
```
gcloud compute routes create ROUTE_NAME \
    --network=vpc-1 \
    --destination=DESTINATION_RANGE \
    --priority=PRIORITY \
    --next-hop-ilb=FORWARDING_RULE
```
Replace the following:
- ROUTE_NAME: the name of the route
- DESTINATION_RANGE: the destination IPv4 addresses for the transit VPC.
- PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority). For more information about route priority, see Routing order.
- FORWARDING_RULE: IP address of a forwarding rule for a internal passthrough Network Load Balancer in vpc-2.
Create a static route in spoke vpc-2 with the transit VPC's IP address as the destination, and the transit VPC's internal passthrough Network Load Balancer IP address as the next hop:
```
gcloud compute routes create ROUTE_NAME \
    --network=vpc-2 \
    --destination=DESTINATION_RANGE \
    --priority=PRIORITY \
    --next-hop-ilb=FORWARDING_RULE
```
Replace the following:
- ROUTE_NAME: the name of the route
- DESTINATION_RANGE: the destination IPv4 addresses for the transit VPC
- PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority); for more information about route priority, see Routing order.
- FORWARDING_RULE: IP address of a forwarding rule for an internal passthrough Network Load Balancer in the transit VPC
Create a return route in the transit VPC to vpc-2, with vpc-2's IP address as the destination, and vpc-2's internal passthrough Network Load Balancer IP address as the next hop:
```
gcloud compute routes create ROUTE_NAME \
    --network=transit \
    --destination=DESTINATION_RANGE \
    --priority=PRIORITY \
    --next-hop-ilb=FORWARDING_RULE
```
Replace the following:
- ROUTE_NAME: the name of the route
- DESTINATION_RANGE: the destination IPv4 address for vpc-2
- PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority); for more information about route priority, see Routing order.
- FORWARDING_RULE: IP address of a forwarding rule for an internal passthrough Network Load Balancer in vpc-2
Next, create a return route in the transit VPC to vpc-1, with vpc-1's IP address as the destination, and vpc-2's internal passthrough Network Load Balancer IP address as the next hop:
```
gcloud compute routes create ROUTE_NAME \
    --network=transit \
    --destination=DESTINATION_RANGE \
    --priority=PRIORITY \
    --next-hop-ilb=FORWARDING_RULE
```
Replace the following:
- ROUTE_NAME: the name of the route
- DESTINATION_RANGE: the destination IPv4 addresses for vpc-2
- PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority); for more information about route priority, see Routing order.
- FORWARDING_RULE: IP address of a forwarding rule for an internal passthrough Network Load Balancer in vpc-2
Finally, create a return route in vpc-2 to vpc-1, with vpc-1's IP address as the destination, and vpc-1's internal passthrough Network Load Balancer IP address as the next hop:
```
gcloud compute routes create ROUTE_NAME \
    --network=vpc-2 \
    --destination=DESTINATION_RANGE \
    --priority=PRIORITY \
    --next-hop-ilb=FORWARDING_RULE
```
Replace the following:
- ROUTE_NAME: the name of the route
- DESTINATION_RANGE: the destination IPv4 addresses for vpc-1
- PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority); for more information about route priority, see Routing order.
- FORWARDING_RULE: IP address of a forwarding rule for a internal passthrough Network Load Balancer in vpc-1

For more information about NVAs, see Network virtual appliances.

Create static routes in a star topology

For this example, assume that you have two edge VPCs, edge-1 and edge-2 that are connected to center VPC center. Suppose that you also have a transit VPC transit that is connected to center through a network virtual appliance (NVA). You want to reach the transit VPC from edge-1, so you configure static routes using the following steps:

First, create a static route in edge-1 with the transit VPC's IP address as the destination, and center's internal passthrough Network Load Balancer IP address as the next hop:
```
gcloud compute routes create ROUTE_NAME \
    --network=edge-1 \
    --destination=DESTINATION_RANGE \
    --priority=PRIORITY \
    --next-hop-ilb=FORWARDING_RULE
```
Replace the following:
- ROUTE_NAME: the name of the route
- DESTINATION_RANGE: the destination IPv4 addresses for the transit VPC
- PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority); for more information about route priority, see Routing order.
- FORWARDING_RULE: IP address of a forwarding rule for an internal passthrough Network Load Balancer in center
Create a static route in center with the transit VPC's IP address as the destination, and the transit VPC's internal passthrough Network Load Balancer IP address as the next hop:
```
gcloud compute routes create ROUTE_NAME \
    --network=vpc-1 \
    --destination=DESTINATION_RANGE \
    --priority=PRIORITY \
    --next-hop-ilb=FORWARDING_RULE
```
Replace the following:
- ROUTE_NAME: the name of the route
- DESTINATION_RANGE: the destination IPv4 addresses for the transit VPC
- PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority); for more information about route priority, see Routing order.
- FORWARDING_RULE: IP address of a forwarding rule for an internal passthrough Network Load Balancer in the transit VPC
Create a return route in the transit VPC to center, with center's IP address as the destination, and center's internal passthrough Network Load Balancer IP address as the next hop:
```
gcloud compute routes create ROUTE_NAME \
    --network=transit \
    --destination=DESTINATION_RANGE \
    --priority=PRIORITY \
    --next-hop-ilb=FORWARDING_RULE
```
Replace the following:
- ROUTE_NAME: the name of the route
- DESTINATION_RANGE: the destination IPv4 addresses for center
- PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority); for more information about route priority, see Routing order.
- FORWARDING_RULE: IP address of a forwarding rule for an internal passthrough Network Load Balancer in center
Next, create a return route in the transit VPC to edge-1, with edge-1's IP address as the destination, and center's internal passthrough Network Load Balancer IP address as the next hop:
```
gcloud compute routes create ROUTE_NAME \
    --network=transit \
    --destination=DESTINATION_RANGE \
    --priority=PRIORITY \
    --next-hop-ilb=FORWARDING_RULE
```
Replace the following:
- ROUTE_NAME: the name of the route
- DESTINATION_RANGE: the destination IPv4 addresses for edge-1
- PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority); for more information about route priority, see Routing order.
- FORWARDING_RULE: IP address of a forwarding rule for an internal passthrough Network Load Balancer in center
Next, create a return route in center to edge-1, with edge-1's IP address as the destination, and edge-1's internal passthrough Network Load Balancer IP address as the next hop:
```
gcloud compute routes create ROUTE_NAME \
    --network=center \
    --destination=DESTINATION_RANGE \
    --priority=PRIORITY \
    --next-hop-ilb=FORWARDING_RULE
```
Replace the following:
- ROUTE_NAME: the name of the route
- DESTINATION_RANGE: the destination IPv4 addresses for edge-1
- PRIORITY: the route priority, which can be from 0 (the highest priority) to 65535 (the lowest priority); for more information about route priority, see Routing order.
- FORWARDING_RULE: IP address of a forwarding rule for an internal passthrough Network Load Balancer in edge-1

Delete static routes

Use the following gcloud compute routes delete command to delete a static route, replacingROUTE_NAME with the name of the route:

  gcloud compute routes delete ROUTE_NAME