Configuring the IPU

Use this information to load the virtio drivers and configure the network for the virtio devices on the IPU.

Before you begin

Make sure that you have:

Installed a Napatech IPU in a server. See Installing a Napatech IPU.
Updated the IPU with an appropriate FPGA image. See OVS Offload Software FPGA Images.
Remote SSH access to the SoC on the IPU via the management port or the USB port. See DN-1385.
Installed the OVS Offload Software package. See Installing OVS Offload Software on the IPU.
Created an OVS bridge. See Creating an OVS Bridge on the IPU.
Configured the network on the host. See Configuring the Host.

About this task

Note: The following prompts are used to indicate which part of the system to run the provided commands on.

soc#: The SoC on the IPU.
host#: The server where the IPU is installed.

Procedure

On the IPU, load the virtio_net driver if it is not loaded.
Check whether the virtio_net driver is loaded.
```
soc# lsmod | grep virtio
```
An output example:
```
virtio_net             65536  0
net_failover           24576  1 virtio_net
```
If virtio_net is not listed, run the following commands.
```
soc# modprobe virtio
soc# modprobe virtio_pci
soc# modprobe virtio_net
```
On the IPU, check the virtio devices.
```
soc# ip -br link
```
After the virtio_net driver is loaded, the virtio devices are recognized as Linux kernel network devices. This is an output example with the bard-metal FPGA image on the IPU.
```
…
…
ens6f3 DOWN 00:e8:ca:11:bf:7d <BROADCAST,MULTICAST>
ens6f4 DOWN 00:e8:ca:11:bf:7c <BROADCAST,MULTICAST>
ens6f5 DOWN 00:e8:ca:11:bf:7b <BROADCAST,MULTICAST>
ens6f6 DOWN 00:e8:ca:11:bf:7a <BROADCAST,MULTICAST>
ens6f7 DOWN 00:e8:ca:11:bf:79 <BROADCAST,MULTICAST>
```
Network device names may vary depending on the kernel version and network configuration. Physical function 7 has a MAC address ending with :79 and physical function 6 has a MAC address ending with :7a. In this case, ens6f7 and ens6f6, respectively.

On the IPU, create namespaces.

Namespaces can be used to isolate network configuration for each physical function and simplify OVS testing. To create 2 namespaces on the same IPv4 subnet as the host, run commands as follows.

soc# ip netns add soc7
soc# ip link set ens6f7 netns soc7 
soc# ip netns exec soc7 ip addr add 192.168.1.37/24 dev ens6f7 
soc# ip netns exec soc7 ip link set ens6f7 up

soc# ip netns add soc6
soc# ip link set ens6f6 netns soc6 
soc# ip netns exec soc6 ip addr add 192.168.1.36/24 dev ens6f6 
soc# ip netns exec soc6 ip link set ens6f6 up

Two namespaces are configured as follows:

Namespace	Kernel net device name	IP address
soc7	ens6f7	192.168.1.37
soc6	ens6f6	192.168.1.36

On the host, check IP addresses.

To check the IP address of the PF7 interface, run the following command.

host# ip netns exec soc7 ip addr

An output example:

1: lo: <LOOPBACK> mtu 65536 qdisc noop state DOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
9: ens6f7: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:e8:ca:11:bf:79 brd ff:ff:ff:ff:ff:ff
    altname enp21s0f7
    inet 192.168.1.37/24 scope global ens6f7
       valid_lft forever preferred_lft forever
    inet6 fe80::2e8:caff:fe11:bf79/64 scope link
       valid_lft forever preferred_lft forever

The following command is to check the IP address of the PF6 interface.

host# ip netns exec soc6 ip addr

An output example:

1: lo: <LOOPBACK> mtu 65536 qdisc noop state DOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
8: ens6f6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 00:e8:ca:11:bf:7a brd ff:ff:ff:ff:ff:ff
    altname enp21s0f6
    inet 192.168.1.36/24 scope global ens6f6
       valid_lft forever preferred_lft forever
    inet6 fe80::2e8:caff:fe11:bf7a/64 scope link
       valid_lft forever preferred_lft forever

On the host, ping between one namespace of the IPU and another namespace of the host to test the connectivity.
For example:
```
host# ip netns exec soc7 ping 192.168.1.36
host# ip netns exec soc7 ping 192.168.1.10
```