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FERMILAB

What, Why and Who?

What is YUM?  (From the official YUM web page)
Yum is an automatic updater and package installer/remover for rpm systems. It automatically computes dependencies and figures out what things should occur to install packages. It makes it easier to maintain groups of machines without having to manually update each one using rpm.

Why we install it?
First and foremost, the reason we are using YUM is for security reasons.  We need a way for Fermi Linux to automatically be updated so people don't have to worry about their machines being compromised.
Second, but still quite important.  We wanted a way for people to install and update packages easily.

Who get's it?
Fermi Linux 9.0.1 has YUM installed by default.  AutoRPM is not installed, only YUM.
Fermi Linux 7.3.1 has YUM installed by default.  AutoRPM is not installed, only YUM.
Fermi Linux 7.1.1 does not currently install YUM.  You have to get it from ftp://linux.fnal.gov/linux/contrib/yum   The same yum works for both 7.3.1 and 7.1.1.  Although it is recommended that you take off AutoRPM if you install YUM, you do not have to.  They simply will both be doing the same thing and will be redundant.

We have created a script that will remove AutoRPM from your 7.1.1 machine, upgrade your rpm, and install yum for you. We have two different versions of this script.
autorpm.to.yum - This is a no nonsense script, that just does the upgrade.
autorpm.to.yum.gentle - This script tries to be more gentle. It checks to see if you have made any changes to autorpm, what they are, how best to do things with the various changes. *Warning - This script is still being developed and may not be as gentle as you want.*

Automatic Software Updates

In order to help the administrators of Fermi Linux machines, we have installed YUM and a pre-configured configuration file that points to a Fermi administered package installation server. Each night YUM will check to see if there are security updates that are needed to be installed. We have complete control over what packages get updated and when.  The Fermi Linux maintainers will make announcements via the linux-users mailing list when we are about to release a patch.

Interactive Software Installation/Updates

In addition to making Fermi Linux machines more secure, yum also makes day to day administration easier.  YUM makes the installation, removal, and finding rpm's easier.  As long as a package is part of the Fermi Linux distribution, you will no longer have to do the runaround of downloading a package, trying to install it, then downloading whatever that depends on, and so forth.  

Here are some of the features of YUM.
For all of these "globs" can be used in the <package name>, so you use names like kde*.
Also, for all the actions that will actually do something to your system, the default is to ask you if that is really what you want to do.  This feature can be overridden with the -y option.

• yum install <package name>
  • Example: yum install nedit
  • Install is used to install the latest version of a package or group of packages while ensuring that all dependencies are satisfied.
• yum update <package name>
  • Example: yum update nedit
  • If run without any packages, update will update every currently installed package.  If one or more packages are specified, Yum will only update the listed packages.  While updating packages, yum will ensure that all dependencies are satisfied.
    
• yum info <package name>
  • Example: yum info nedit
  • Would return what you would get from doing an 'rpm -qi nedit', except that if you don't have nedit installed, it get's this information from the yum repository headers.  If you have an older version of nedit than the version in the repository, it will display both the installed, and the uninstalled info.
    
• yum provides <file name>
  • Example: yum provides /bin/login
  • Would return what you would get from doing an 'rpm -qf /bin/login', except as with yum info, you don't have to have /bin/login installed.  It get's the information from both the local rpm database, and the yum repository.
• yum remove <package name>
  • Example: yum remove krb5-libs
  • Will remove not only the package you tell it, but also the packages that depend on it, and those that depend on them, and so forth.  Before it erases these packages, it lists what all will be erased, and asks if that is what you want to do.  This is a good way to find all the dependancies of a package, just don't hit Y at the end
• yum list
• yum list updates
• yum list installed
• yum list [pkgname]
• list can be used to list various information about available and installed packages. The list options are hopefully obvious to people.

TIPS

With the release of yum-conf-0.9.3-1f2.noarch.rpm is is now easier to switch between the stable Fermi Linux release and the Rolling release. This is good if you want to just update one specific product (such as Mozilla) but don't want to have to mess with your yum.conf file, or switch your whole system to the rolling release.
There are two main changes with the conf files. First there is now three conf files. There is the normal default /etc/yum.conf, but there is also two extra called /etc/yum.conf.731 and /etc/yum.conf.73rolling (or it will be 71 instead of 73 if you are running 711). We have also move where the yum cache's to better accomodate the change.
Please note that none of these changes affect your normal nightly yum update.

So if you are running a 731 machine, but want to get the new mozilla (or kernel, or yum or anything) that is in 73rolling, you will just run the following.

• yum -c /etc/yum.conf.73rolling update mozilla*