Using an HSCI interface as a base device for MacVTap or OpenVSwitch

Red Hat Enterprise Linux 8.6 LPAR mode

You can use an HSCI network device as the base device for a MacVTap or OpenVSwitch connection. You can, for example, attach KVM virtual servers to the converged network.

Before you begin

It is useful to define the PNET ID for the HiperSockets channel and the OSA or RoCE adapters to mark them as part of the same network segment.

About this task

To attach KVM virtual servers to a converged network, you define the HSCI device as a source device in the domain XML of the virtual server.

The following example assumes that there is an HiperSockets interface enc8410, an OSA interface encb040, and you want to create an HSCI interface hsci8410. Then you can use the HSCI interface to set up a MacVTap connection with two KVM virtual servers.

Procedure

On the KVM host, define the HiperSockets interface as layer 2. Issue a command of the form:
```
# chzdev -e <device_ID> layer2=1
```
For example, if the device ID of the HiperSockets device is 8410:
```
# chzdev -e 8410 layer2=1
QETH device 0.0.8410:0.0.8411:0.0.8412 configured
```

Define the OSA interface with flooding and mcast_flooding enabled. Issue a command of the form:

# chzdev -e <device_ID> vnicc/flooding=1 vnicc/mcast_flooding=1

For example, if the OSA device ID is b040:

# chzdev -e b040 vnicc/flooding=1 vnicc/mcast_flooding=1
QETH device 0.0.b040:0.0.b041:0.0.b042 configured
   Adding layer2=1 to active configuration (required by vnicc/mcast_flooding)
   Adding layer2=1 to persistent configuration (required by vnicc/mcast_flooding)

Create the converged HSCI interface. Issue a command of the form:

# hsci add <HipSock_if> <OSA_if>

For example, if the HiperSockets interface is enc8410 and the OSA interface is encb040:

# hsci add enc8410 encb040
Verifying net dev encb040 and HiperSockets dev enc8410
Adding hsci8410 with a HiperSockets dev enc8410 and an external dev encb040
Added HSCI interface hsci8410

Optional: Check that the HSCI interface was created. Use the hsci show command.

For example:

hsci show
HSCI       PNET_ID        HiperSockets            External
------------------------------------------------------------
hsci8410   NET1           enc8410                 encb040

What to do next

You can use the HSCI interface as the base for a MacVTap or an OpenVSwitch connection on a KVM virtual server, as illustrated in Figure 1.

Two KVM virtual servers are connected by a MacVTap interface, connected to an HSCI interface, in turn connected to the external network — Figure 1. MacVTAp connection with two KVM virtual servers

See KVM Virtual Server Management, SC34-2752 for how to configure a network interface in the domain configuration XML of the KVM virtual servers.