List packages from 3 party vendors (Not Red Hat).

 rpm -qa --qf '%{NAME} %{VENDOR}\n' | grep -v "Red Hat, Inc."
 

rpm -qa --qf '%{NAME} %{SIGGPG:pgpsig} %{SIGPGP:pgpsig} \n' 
 

rpm -qa --last

rpm -q gpg-pubkey --qf '%{name}-%{version}-%{release} --> %{summary}\n' 

rpm -e --allmatches gpg-pubkey-<pub signature>

rpm2cpio httpd-2.2.3-31.el5_4.2.x86_64.rpm | cpio -idmv

rpm2cpio logrotate-1.0-1.i386.rpm |cpio -ivd etc/logrotate.conf

You might want to download packages without installing them.

Make sure yum-downloadonly plugin is installed

yum install yum-downloadonly

Update system but only download packages do not install them

yum update -y --downloadonly

Default download cache is /var/cache/yum/. This cn be overidden with –downloaddir option

Getting conflict errors between 32bit and 64 bit packages when doing yum update

Transaction Check Error:

file blablabla from install of hal-0.5.8.1-62.el5.i386.rpm conflicts with file from package hal-0.5.8.1-62.el5.x64.rpm

rpm -Uvh --force /var/cache/yum/rhel-x86_64-server-5/packages/hal-0.5.8.1-62.el5.i386.rpm

Now re-run yum update. Now everything works fine.