Chapter 1 About the Unbreakable Linux Network

This chapter describes what the Unbreakable Linux Network (ULN) is and how it works. It includes a description of the packages required for a system to connect to ULN and also describes how channels are named and how software errata are released to the different channels.

If you have a subscription to Oracle Unbreakable Linux support, you can use the comprehensive resources of the Unbreakable Linux Network (ULN). ULN offers software patches, updates, and fixes for Oracle Linux and Oracle VM, as well as information on yum, Ksplice, and support policies. You can also download useful packages that are not included in the original distribution. The ULN Alert Notification Tool periodically checks with ULN and alerts you when updates are available. You can access ULN at, where you will also find instructions for registering with ULN, for creating local yum repositories, and for switching from the Red Hat Network (RHN) to ULN.

If you want to use yum with ULN to manage your systems, you must register the systems with ULN and subscribe each system to one or more ULN channels. When you register a system with ULN, the channel that contains the latest version is chosen automatically, according to the architecture and operating system revision of the system. See Chapter 3, ULN Registration for more information.

When you run the yum command, it connects to the ULN server repository and downloads the latest software packages in RPM format onto your system. yum then presents you with a list of the available packages so that you can choose which packages you want to install.