ServerBuddies Support Blog

Upgrading Your Redhat Server.

Check your kernel release before upgrade.

If run without any packages, update will update every currently installed package.

After the upgrade check the kernel release.

yum update

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.

If no package matches the given package name(s), they are assumed to be a shell glob and any matches are then installed. If the –obsoletes flag is present yum will include package obsoletes in its calculations - this makes it better for distro-version changes, for example: upgrading from somelinux 8.0 to somelinux 9.

yum upgrade : Is the same as the update command with the –obsoletes flag set.

yum is an interactive, automated update program which can be used for maintaining systems.

Yum Options:

FILES

SEE ALSO

Chkconfig

The chkconfig command can also be used to activate and deactivate services. If you use the chkconfig –list command, you will see a list of system services and whether they are started (on) or stopped (off) in runlevels 0-6 (at the end of the list, you will see a section for the services managed by xinetd.

If you use chkconfig –list to query a service managed by xinetd, you will see whether the xinetd service is enabled (on) or disabled (off). For example, the following command shows that finger is enabled as an xinetd service:

More importantly, chkconfig can be used to set a service to be started (or not) in a specific runlevel. For example, to turn nscd off in runlevels 3, 4, and 5, use the command:

Description

rpm is a powerful Package Manager, which can be used to build, install, query, verify, update, and erase individual software packages. A package consists of an archive of files and meta-data used to install and erase the archive files.

RPM Commands:

• To install a RPM package.

• To uninstall a RPM package.

• To upgrade a RPM package. RPM automatically uninstall the old version of the foo package and Install the new package.

• To query all installed packages.

• To query a RPM package.

• To display package information.

• To list files in installed package.

• To find out which package owns a file?

• How to find out the list files in RPM file.

• To verify an installed package.

Note:

–replacefiles

Install the packages even if they replace files from other, already installed, packages.

–replacepkgs

Install the packages even if some of them are already installed on this system.

–test

Do not install the package, simply check for and report potential conflicts.

Binary RPMs and Source RPMs

There are two main types of RPM packages: binary (or applications) and source. A binary RPM has been compiled for a particular architecture.

A source RPM (SRPM) package typically contains a gzipped tar archive with the source files, and an RPM spec file.

To compile and install a source RPM package on redhat system, you can do the following:

Type:

As root, install the binary RPM. It will be located in the directory- /usr/src/redhat/RPMS/i386.

* elinks - lynx-like alternative character mode WWW browser.

Working behind the scenes of the package manager is the RPM database, stored in /var/lib/rpm. It consists of a single database (Packages) containing all of the meta information of the installed rpms and multiple databases used for indexing purposes.