Creating an unbound GRE tunnel

Creating an unbound GRE tunnel in the UI

You can create an unbound GRE tunnel on an existing transit gateway, or when you are creating a new transit gateway.

To create an unbound GRE tunnel, follow these steps:

1. Select one of the following choices:

   • To create an unbound GRE tunnel on an existing transit gateway:

     1. From your browser, open the IBM Cloud console and log in to your account.
     2. Select the Navigation Menu icon from the upper left, then click Interconnectivity > Transit Gateway.
     3. Click the name of the transit gateway where you want to add a connection.
     4. Click Add connection in the Connections tab.

   • To create an unbound GRE tunnel while creating a transit gateway:

     1. From your browser, open the IBM Cloud console and log in to your account.
     2. Select the Navigation Menu icon from the upper left, then click Interconnectivity.
     3. Click Transit Gateway from the left navigation window. Then, click Create transit gateway.
     4. Enter the transit gateway name, resource group, and location.

2. Choose Unbound GRE tunnel as your network connection type.

3. Enter the tunnel name.

4. Select the base network type and whether this is a connection to a network in another account.

5. If this connection is to a network in another account, enter the account ID.

6. Choose an availability zone in which to create the tunnel.

7. Configure the remaining parameters for the connection:

   • Enter the remote gateway IP for the endpoint of the GRE tunnel.

   • Enter a /30 remote tunnel IP for both ends of the tunnel, for example 192.168.103.2.

   • Enter the local gateway IP address^[1] that the transit gateway uses to host the underlay network for the GRE tunnel. This user-selected IP address is configured on the transit gateway GRE tunnel after the tunnel is created.

   • Enter a /30 local tunnel IP for both ends of the tunnel, for example 192.168.103.1.

   • Optionally, enter the remote BGP ASN, which is a valid 2 or 4 byte value of your choosing.

     You can leave this blank and a unique ASN is assigned.

   • Enter a connection name for your GRE tunnel.

8. Click Add to create the GRE tunnel.

Creating an unbound GRE tunnel from the CLI

Create an unbound Generic Routing Encapsulation (GRE) tunnel connection on a given transit gateway.

ibmcloud tg connection-create-gre|ccgre GATEWAY_ID --name NAME --zone ZONE --local-gateway-ip LOCAL_GATEWAY_IP --local-tunnel-ip LOCAL_TUNNEL_IP --remote-gateway-ip REMOTE_GATEWAY_IP --remote-tunnel-ip REMOTE_TUNNEL_IP [--network-type NETWORK_TYPE] [--base-connection-id BASE_CONNECTION_ID] [--base-network-type BASE_NETWORK_TYPE] [--network-account-id NETWORK_ACCOUNT_ID] [--remote-bgp-asn REMOTE_BGP_ASN] [--output json]

Where:

GATEWAY_ID

ID of the gateway where the new connection is bound.

--name

Name of the new connection.

--zone

Availability zone for the GRE tunnel. Example: us-south-1

--local-gateway-ip

Local gateway IP address for the GRE tunnel connection.

--local-tunnel-ip

Local tunnel IP address for the GRE tunnel connection.

--remote-gateway-ip

Remote gateway IP address for the GRE tunnel connection.

--local-tunnel-ip

Remote tunnel IP address for the GRE tunnel connection.

--network-type

Optional: The type of GRE tunnel to create, either gre_tunnel or unbound_gre_tunnel. The default is gre_tunnel.

--base-connection-id

Optional: The ID of the classic network connection that will be the underlay for the GRE tunnel. Used only for gre_tunnel type connections.

--base-network-type

Optional: The type of network the GRE tunnel is targeting (classic). Used only for unbound_gre_tunnel type connections.

--network-account-id

Optional: The ID of the IBM Cloud account to use for creating a cross account GRE tunnel to a classic network. Used only for unbound_gre_tunnel type connections.

--remote-bgp-asn

Optional: If the remote BGP ASN is not specified, one is generated.

--output json

Optional: Shows the output in JSON format.

--help | -h

Optional: Get help on this command.

ibmcloud tg connection-create-gre $gateway  --network-type unbound_gre_tunnel --name unbound-gre-connection --base-network-type classic  --zone us-south-2 --local-gateway-ip 192.168.100.1 --local-tunnel-ip 192.168.101.1 --remote-gateway-ip 10.242.63.12 --remote-tunnel-ip 192.168.101.2

Creating an unbound GRE tunnel with the API

curl -X POST "https://transit.cloud.ibm.com/v1/transit_gateways/test/connections?version=2022-01-27" -H "accept: application/json" -H "Content-Type: application/json" -d "{\"local_gateway_ip\":\"192.168.100.1\",\"local_tunnel_ip\":\"192.168.129.2\",\"name\":\"Transit_Service_BWTN_SJ_DL\",\"network_type\":\"unbound_gre_tunnel\",\"base_network_type\":\"classic\",\"remote_bgp_asn\":65010,\"remote_gateway_ip\":\"10.242.63.12\",\"remote_tunnel_ip\":\"192.168.129.1\",\"zone\":{\"name\":\"us-south-1\"}}"

{
  "local_gateway_ip": "192.168.100.1",
  "local_tunnel_ip": "192.168.129.2",
  "name": "Transit_Service_BWTN_SJ_DL",
  "network_type": "unbound_gre_tunnel",
  "base_network_type": "classic",
  "remote_bgp_asn": 65010,
  "remote_gateway_ip": "10.242.63.12",
  "remote_tunnel_ip": "192.168.129.1",
  "zone": {
    "name": "us-south-1"
  }
}

{
  "created_at": "2020-03-31T12:08:05Z",
  "id": "1a15dca5-7e33-45e1-b7c5-bc690e569531",
  "name": "example-connection",
  "network_type": "unbound_gre_tunnel",
  "base_network_type": "classic",
  "status": "pending",
  "updated_at": "2020-03-31T12:08:05Z"
}

Creating a GRE tunnel connection using Terraform

You can specify the following argument references for your resource when creating an unbound Generic Routing Encapsulation (GRE) tunnel connection:

resource "ibm_tg_connection" "test_ibm_tg_connection" {
  gateway            = ibm_tg_gateway.test_tg_gateway.id
  network_type       = "unbound_gre_tunnel"
  base_network_type  = "classic"
  name               = "myconnection"
  local_gateway_ip   = 192.168.0.1
  local_tunnel_ip    = 10.0.0.1
  remote_bgp_asn     = 36361
  remote_gateway_ip  = 192.168.1.1
  remote_tunnel_ip   = 10.0.1.1
  zone               = us-east
}