Wednesday Apr 17, 2013

How the Oracle Linux Update Channels are Structured

Beer Taps by Jamie C2009, on Flickr
"Beer Taps" by Jamie C2009 (CC BY 2.0).

Oracle Linux distribution releases are identified by a major version like "Oracle Linux 6" or "Oracle Linux 5", followed by an update release number, e.g. "Oracle Linux 6 Update 3" or "Oracle Linux 6.3" in short. Every Oracle Linux distribution release is freely available as ISO installation images from the Oracle Software Delivery Cloud (formerly known as E-Delivery), as well as individual RPM packages, broken up by update releases. These are published via "channels" (or "yum repositories") from the Unbreakable Linux Network (ULN) and our public yum repository

Security patches and critical bug fixes (errata) for individual packages that are being released in between update releases are published immediately via the corresponding _latest yum repositories and ULN channels at the same time. If you want to ensure that your system is always up to date and fully patched, make sure to have it subscribed to the _latest channel (e.g. ol6_latest). And you don't even need to purchase a support subscription for that, if you use the public yum repositories!

Update releases of a major distribution version are primarily "checkpoints", an accumulation of all patches that have been published since the last update release has been made available. They help to reduce lengthy patch/update procedures that would have to be performed if you would always have to start a new installation from the very first release of a new major version. Update releases within a major version are binary compatible. An application that was installed and tested on Oracle Linux 6.1 will still run on Oracle Linux 6.4.

In addition to the _latest channel, ULN also provides so-called _patch channels, one per update release (e.g. ol6_u4_x86_64_patch for Oracle Linux 6.4 on x86_64). These _patch channels contain all RPM updates that have been published after a new update release (e.g. 6.4) has been released. They are kept up to date with each new update package that is made available. So they allow you to keep a certain update level of the distribution up to date without risking rolling forward to a new update release version automatically (which is what happens when your system is subscribed to the _latest repository).

However, one thing to keep in mind is that these channels actually stop receiving updates once a new update release (e.g. 6.4) has been made available. At this point you need to "go with the flow" and plan your update to the next update release (and its associated _patch channel), if you don't want to risk running an un-patched system.

I'd like to give you an alternative explanation of this channel structure, using software development and source code version control as an analogy. In revision control terms, you could consider the _latest channel the "trunk" of the distribution, a stream of packages that is always up to date and also rolls forward the distribution's update version in regular intervals. The _base channels could be considered "tags" or "snapshots" of the _latest package stream. They represent the state of a major distribution version (e.g. Oracle Linux 6) at a certain point in time, identified by a minor version number (e.g. 6.3). They are being packaged and released in the form of an ISO image as well. The _patch channels could be considered "branches" that are branched off a certain tag and are being kept up to date with the "trunk" until a new update release has been tagged.

I hope this explanation helps understanding the various channels and their purposes!

- Lenz Grimmer

Follow me on:
Personal Blog | Facebook | Twitter | Linux Blog |

Tuesday Apr 16, 2013

Evaluating Oracle Solaris and Oracle Linux From Your Laptop

Evaluating Oracle Linux From Inside VirtualBox

After importing your Oracle Linux virtual image, you can use the yum install command to download additional packages into your Linux environment. Yuli explains how.

But what's really cool about evaluating an OS from inside VirtualBox is that you can assign each virtual image a unique IP address, and have it communicate with the outside world as if it were its own physical machine on the network. Yuli describes how to do this, and also how to install guest additions to, for instance, share files between the guest and host systems.

Evaluating Oracle Solaris 11 From Inside VirtualBox

In this article Yuli shows you how to create and manage user accounts with either the GUI or the CLI, how to set up networking, and how to use the Service Management Facility (SMF) to, for instance, control SSH connections to the outside world.

Both article cover the basics to get you started, but also very valuable are the links that Yuli provides to help you move further along in your evaluation.

- Rick

Follow me on:
Blog | Facebook | Twitter | YouTube | The Great Peruvian Novel

Friday Apr 05, 2013

Migrating to Oracle Linux: How to Identify Applications To Move

source

One of the first things you need to make when migrating from SUSE Linux to Oracle Linux is an inventory of your applications. A package management tool such as Yet Another Setup Tool (YAST) is a big help here. So is the rpm command. Here are some ways to use it.

To List All The Installed Packages

Use the -qa option.

# rpm –qa
filesystem-11.1.3.5.3
sles-release-DVD-11.2.1.234
...

To Save the Output in a File

You can move that file to any location and, anytime later,search through the package list saved there to look for a package of interest:

# rpm –qa > rpmlist.txt

To Sort the Packages

To see the installed packages sorted by install time, use --last. The packages installed most recently will appear at the top of the list, followed by the standard packages installed during the original installation:

# rpm –qa --last
VirtualBox-4.2-4.2.6_82870_sles11-0-1
...

To Find Out If A Particular Component Is Installed

To find out whether a particular component is installed and what version it is, use the name option. For example:

# rpm –qa python
python-2.6.0-8.12.2

To Find Out What Dependencies a Package Has

Use the -qR option:

# rpm –qR python-2.6.0-8.12.2
python-base = 2.6.0
rpmlib(VersionedDependencies) <= 3.0.3-1
...

The Linux Migration Guide

You can find out more about migration steps with either rpm or YaST, including the benefits of migrating to Oracle Linux, by downloading the white paper from here:

Download the Oracle Linux Migration Guide

- Rick

Follow me on:
Blog | Facebook | Twitter | YouTube | The Great Peruvian Novel

About

Contributors:
Rick Ramsey
Kemer Thomson
and members of the OTN community

Search

Archives
« April 2013 »
SunMonTueWedThuFriSat
 
2
6
7
8
10
13
14
19
20
21
22
24
25
27
28
29
    
       
Today
Blogs We Like