Types of distribution media for central site distribution
The types of distribution media or methods available to the central system for central site distribution are image catalog (optical or tape), shared virtual optical images using the Network File System, tape media, digital video disc (DVD), CD-ROM, and using the Duplicate Optical (DUPOPT) command or Duplicate Tape (DUPTAP) command.
Each distribution media has advantages and disadvantages. Determine which media suits your computing environment.
- Image catalog
- This media requires disk space to hold all virtual images
created on the central system and distributed to the target systems. If you
have ample storage, this option is cost-effective and convenient.
First, prepare the central system to distribute virtual images; then create the distribution media and distribute using FTP. You can also create DVD for central site distribution and then add the DVD to an image catalog and distribute using FTP. Or you can create the virtual images, convert them to DVD or CD-ROM (for optical devices) or tape media (for tape devices), and distribute the physical media. Using virtual images as central site distribution media gives you flexibility and is particularly useful for optical media verification, unattended installations, and upgrading software within a network.
Virtual tape provides higher availability and shorter backup times than the other forms of media. Virtual tape devices can perform the same tasks as physical tape except that you cannot use the Save Storage (SAVSTG) command with a virtual tape device. For further details, see the topic Virtual tape.
For more information about requirements when using image catalogs as the distribution media for central site distribution, see Preparing for virtual optical storage.
- Virtual optical device that uses images shared by a the Network File System
- A special type of virtual optical device (632B; model 003) supports virtual image files on a remote system in the network. A image directory identifies a network path on the central system that contains the virtual image files that are prepared for use with a target system. A virtual optical device can be used to install additional licensed programs or PTFs. For further details, see Virtual optical storage using the Network File System.
- Tape
- High-speed tape is the fastest way to distribute the software involved in a full-system upgrade or the software of a logical partition. However, tape hardware and media is more costly than DVD hardware and media.
- DVD
- DVD is slower than high-speed tape, but is more cost-effective.
- CD-ROM
- Refer to Using CD-ROM in Distributing iSeries Software
for information about using only CD-ROM as the distribution media
for central site distribution. - Duplicate Optical command
- You can use the Duplicate Optical (DUPOPT) command to create actual media from a virtual image of the central site media.
- Duplicate Tape command
- The Duplicate Tape (DUPTAP) command can be used to create actual tape media from a virtual image of the central site media. The format of the virtual tape images needs to be compatible with your physical tape device.