Creating and Enabling a Flex Network

Flex Network Task Map

This task map describes the steps required to establish a Flex network between Private Cloud Appliance and an external system such as Oracle Exadata or Oracle Database Appliance.

Other Considerations

When implementing a Flex network, consider the following:

• If a VM connected to a Flex network must also be accessed from a domain controller, you need to configure a second VNIC for that VM. See Creating and Attaching a Secondary VNIC.

• Use an Internet Gateway (public subnet) for Domain Controller access using the primary VNIC.

• Use a Dynamic Routing Gateway (private subnet) to access the Flex network.

• Use separate Route Tables: one for the Internet Gateway with 0.0.0.0/0 and one for the DRG with a specific route rule for the Flex network.

• Update Security Lists as needed to enable ingress traffic.

Flex Network with Route Table

In its original design, a flex network provides direct connectivity between a VCN and external devices, for example Oracle Exadata nodes or a ZFS Storage Appliance. This design is known as edge mode, and allows you to optionally advertise the flex network from the spine switches to the on-premises network.

A flex network in hub mode uses a gateway on the outside of Private Cloud Appliance instead of direct connections, to route traffic between external devices in an on-premises network and compute instances in a VCN. Flex network access is controlled by a route table, which is configured through the gatewayIp parameter.

Traffic between VCNs can also be routed through a flex network, for example if a firewall connected to the flex network needs to inspect the traffic.

Up to 6 route table entries can be specified in a flex network configuration. The syntax is as follows:

• "r:" - route table entry (1 to 6)

• "net_x" - destination subnet

• "gw_x" - gateway IP for the associated subnet

• ":" (colon) - separator between route table entries

r:<net_1>,<gw_1>:<net_2>,<gw_2>:<net_n>,<gw_n>

For example:

r:10.25.0.0/26,10.212.3.8:172.16.48.0/22,10.212.3.30:0.0.0.0/0,10.212.3.15

adds route table entries for:

10.25.0.0/26 via 10.212.3.8
172.16.48.0/22 via 10.212.3.30
0.0.0.0/0 (default) via 10.212.3.15

Required Parameters

To set up a network connection between Private Cloud Appliance and an external system, you need this set of parameters:

Valid speeds and valid port configurations are related. The following table shows the valid port configurations based on speed selected. Ports must be bonded on the external system side to match the Private Cloud Appliance configuration.

Adding the New Flex Network

Using the Service Web UI

1. Determine the Flex network parameters. See Required Parameters

2. In the Dashboard, click the Racks quick action tile.

3. In the PCA Config navigation menu on the Racks page, click Flex Networks.

4. In the top-right corner above the table, click Create Flex Network.

5. Fill out the Flex Network form using the parameters you collected in advance.

   By default the network is not advertised to the data center network. You have to click the slider to set it to "on"/"true".

6. Click Submit to create the new network. It appears in the Flex Networks table and its Lifecycle State changes to Available when the configuration has been applied successfully.

7. Next, add a subnet to the Flex network. See Enabling Flex Network Access.

Using the Service CLI

1. Determine the Flex network parameters. See Required Parameters

2. Create the Flex network by entering the parameters.

   PCA-ADMIN> create flexNetwork cidr=10.nn.nn.0/24  \
   spine1Ip=10.nn.nn.1 spine2Ip=10.nn.nn.2 spinevip=10.nn.nn.3 \
   vlan=900 gatewayIp=10.nn.nn.10 ports=7/1 advertiseNetwork=false
   Status: Success
   JobId: unique_id

3. Next, add a subnet to the Flex network. See Enabling Flex Network Access.

Enabling Flex Network Access

Enable access from a subnet to the Flex network through the Service CLI. For Flex network access from that subnet, ensure that the configured IP address ranges of Flex networks do not overlap.

Subnets that have been granted access, appear in the Flex network detail page under Access Lists, grouped by their parent VCN.

Using the Service CLI

1. Get the OCID of the Flex network you want to enable, using the list FlexNetwork command.

2. Enable access to a configured Flex network.

   PCA-ADMIN> flexNetworkEnableAccess flexNetworkId=ocid1.exadata.unique_id \
   subnetId=ocid1.subnet.unique_id
   Status: Success
   Data:
    id
    --
    ocid1.vcn.unique_id

3. If you are using a secondary VNIC to access the Flex network, you must add a route to the Flex network CIDR address range for interface eth1 (the secondary VNIC). Sign in to the compute instance configured with the secondary VNIC to add the route.

   [root@hostname]# Flex-CIDR-address-range via gateway dev vlan-interface

   For example, if the Flex address range is 192.168.0.0/24 and the gateway is 192.168.0.1 and the VLAN interface is bond0.900:

   [root@hostname]# 192.168.0.0/24 via 192.168.0.1 dev bond0.900

   This entry appears as a second interface in the IP routing table:

   Destination Gateway      Genmask       Flags Metric Ref Use Iface
    . . . . . . . . . . . . . . . . . . . . 
    192.168.1.0 192.168.1.1 255.255.255.0 0     0      0       eth0 
    192.168.0.0 192.168.0.1 255.255.255.0 0     0      0       eth1 

   A ping from the secondary VNIC, eth1, now succeeds to the Flex network.