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Configure an additional network

After you have created the NetworkAttachmentDefinition object and applied it, you can configure an additional network.

In this example, the bridge type additional network is used. You can also use this workflow for other network types.

Prerequisites

You created and applied the NetworkAttachmentDefinition object configuration.

Procedure

Verify that the bridge was created on the host by running the following command:

$ ip a show br-test

Example output

22: br-test: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 96:bf:ca:be:1d:15 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::34e2:bbff:fed2:31f2/64 scope link
       valid_lft forever preferred_lft forever

Configure an IP address for the bridge by running the following command:
```
$ sudo ip addr add 10.10.0.10/24 dev br-test
```

Verify that the IP address configuration is added to the bridge by running the following command:

$ ip a show br-test

Example output

22: br-test: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 96:bf:ca:be:1d:15 brd ff:ff:ff:ff:ff:ff
    inet 10.10.0.10/24 scope global br-test
       valid_lft forever preferred_lft forever
    inet6 fe80::34e2:bbff:fed2:31f2/64 scope link
       valid_lft forever preferred_lft forever

Confirm that the IP address is configured as expected.

Verify the IP address of the pod by running the following command:

$ oc get pod test-bridge --output=jsonpath='{.metadata.annotations.k8s\.v1\.cni\.cncf\.io/network-status}'

Example output

[{
    "name": "ovn-kubernetes",
    "interface": "eth0",
    "ips": [
        "10.42.0.17"
    ],
    "mac": "0a:58:0a:2a:00:11",
    "default": true,
    "dns": {}
},{
    "name": "default/bridge-conf",
    "interface": "net1",
    "ips": [
        "10.10.0.20"
    ],
    "mac": "82:01:98:e5:0c:b7",
    "dns": {}

Confirm that the bridge additional network is attached as expected-"default/bridge-conf".

Optional: You can use oc exec to access the pod and confirm its interfaces by using the ip command:

$ oc exec -ti test-bridge -- ip a

Example output

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eth0@if21: <BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue
    link/ether 0a:58:0a:2a:00:11 brd ff:ff:ff:ff:ff:ff
    inet 10.42.0.17/24 brd 10.42.0.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::858:aff:fe2a:11/64 scope link
       valid_lft forever preferred_lft forever
3: net1@if23: <BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue
    link/ether 82:01:98:e5:0c:b7 brd ff:ff:ff:ff:ff:ff
    inet 10.10.0.20/24 brd 10.10.0.255 scope global net1
       valid_lft forever preferred_lft forever
    inet6 fe80::8001:98ff:fee5:cb7/64 scope link
       valid_lft forever preferred_lft forever

In the example the pod is attached to the 10.10.0.20 IP address on the net1 interface as expected.

Confirm that the connection is working as expected by accessing the HTTP server in the pod from the MicroShift host. Use the following command:
```
$ curl 10.10.0.20:8080
```
Example output
```
Hello MicroShift
```