Virtual I/O in a logical partition running Linux

 

Virtual I/O resources are devices owned by the hosting i5/OS^® partition that provides I/O function to the logical partition.

The iSeries™ Linux kernel and i5/OS support several different kinds of virtual I/O resources. They are virtual console, virtual disk unit, virtual CD, virtual tape, and virtual Ethernet.

Virtual console provides console function for the logical partition through an i5/OS partition. The virtual console can be established to the server or to the primary partition. The use of the virtual console allows the installation program to communicate with the user prior to networking resources being configured. It can also be used for troubleshooting server errors.

Virtual disk unit can only be provided by a server. Virtual disk provides access to NWSSTG virtual disks for Linux. By default, the CRTNWSSTG command creates a disk environment with one disk partition formatted with the FAT16 file system. The Linux installation program will reformat the disk for Linux or you can use Linux commands such as fdisk and mke2fs to format the disk for Linux.

Virtual CD is needed to support the installation of Linux and is only provided by a server. By default, a Linux partition can see all CD drives on the logical partition. You can change an option on the NWSD to restrict Linux from accessing some or all of those drives. See Create a network server description and a network server storage space for more information on changing NWSD attributes.

Virtual tape provides access to the i5/OS tape drives from a logical partition. By default, a logical partition can see all tape drives on the hosted partition. You can change an option on the NWSD to restrict Linux from accessing some or all of those drives. See Create a network server description and a network server storage space for more information on changing NWSD attributes.

Virtual Ethernet provides the same function as using a 1 Gigabyte (GB) Ethernet adapter. A logical partition can use virtual Ethernet to establish multiple high speed inter-partition connections. i5/OS and Linux partitions can communicate with each other using TCP/IP over the virtual Ethernet communication ports. Refer to Use virtual Ethernet in a logical partition for more information on virtual Ethernet.

For additional information about how your company might use logical partition with virtual I/O resources, see Logical and guest partition scenarios.

 

Parent topic:

Plan to run Linux in a logical partition