Q. How can I know what packages are available for binary update under Fedora / RHEL / CentOS Linux version 5 server? How do I list all outdated packages? How do I apply update / patches to system?

A. CentOS / RHEL / Fedora Linux version 5 and above supports yum command (yum is an interactive, automated update program which can be used for maintaining systems using rpm). It can list all packages which could be updated from a shell prompt.

First, Login as the root user

Type the following command at shell prompt to list all outdated packages:
# yum list updates
Output:

Loading "installonlyn" plugin
Loading "rhnplugin" plugin
Setting up repositories
rhel-x86_64-server-vt-5   100% |=========================| 1.2 kB    00:00     
rhel-x86_64-server-5      100% |=========================| 1.2 kB    00:00     
Reading repository metadata in from local files
Updated Packages
tzdata.noarch                            2007k-1.el5            rhel-x86_64-serv

You can also try to locate specific packages:
# yum list updates package-name
# yum list updates "*apache*"
# yum list updates "regex"
To updated packages, enter:
# yum update

A note about RHEL version <= 4.x

RHEL version 4.0 and below uses up2date command. It has -l option to show you what package updates are available for download and installing the same.
# up2date -l
To check for and update all RPM(S), enter:
# up2date -u

See also:

• Debian/Ubuntu Linux: How do I know what packages are available to be updated on my Debian / Ubuntu Linux system?
• FreeBSD : How do I know what packages are available to be updated on my FreeBSD Server system?