Main steps for setting up a network interface

6.10 LPAR mode z/VM guest

The main steps apply to all network device drivers that are based on ccwgroup devices (for example, qeth and lcs devices).

The steps that follow apply to Linux® on z/VM® and to Linux in LPAR mode. For Linux on KVM, these steps are performed for you on the KVM host. The steps can be different for the different device drivers.

  1. Create a network device by combining suitable subchannels into a group device. The device driver then creates directories that represent the device in sysfs.
  2. Configure the device through its attributes in sysfs. Some devices have attributes that can or must be set later when the device is online or when the connection is active.
  3. Set the device online. This step associates the device with an interface name and thus makes the device known to the Linux network stack. For devices that are associated with a physical network adapter it also initializes the adapter for the network interface.
  4. Configure and activate the interface. This step adds interface properties like IP addresses, netmasks, and MTU to the network interface and moves the network interface into state "up". The interface is then ready for user space (socket) programs to run connections and transfer data across it.

To configure devices, use the chzdev command, see Persistent device configuration.