After issuing the command yum update, you may end up with errors like so:

Error: asterisk14-res_fax conflicts with asterisk14-addons-core
Error: asterisk14-res_fax_digium conflicts with asterisk14-addons-core

So, after doing some research you’ll quickly find this is simply a licensing issue and it is safe to force install the RPMs (digium thread)

First let’s install yumdownloader to make getting the RPMs easier.

yum install yum-utils

Now download both of the RPMs we will need into the current directory.

yumdownloader asterisk14-res_fax
yumdownloader asterisk14-res_fax_digium

Most recently, before force installing these RPMs, I went ahead and updated everything else, skipping these packages using –skip-broken

yum update --skip-broken

Then I force installed the other two RPMs

rpm -Uvh --nodeps asterisk14-res_fax-{VERSION}.rpm asterisk14-res_fax_digium-{VERSION}.rpm

Once upgraded, I issued another full update again to verify everything is good

yum update

“No Packages marked for Update”

First, make sure you’re logged in as root:

su -

Install with up2date:

1. Add the following line to /etc/sysconfig/rhn/sources:

yum dag http://apt.sw.be/redhat/el4/en/$ARCH/dag

Note: Your source line may be different depending on your release. You can find the correct line to use here: http://dag.wieers.com/rpm/FAQ.php#B5

2. Add the following line to /etc/ld.so.conf:

/usr/local/lib

3. Finally, execute each of the following in order:

ldconfig -v
rpm -Uvh ftp://rpmfind.net/linux/dag/redhat/el4/en/i386/dag/RPMS/rpmforge-release-0.3.6-1.el4.rf.i386.rpm
up2date ffmpeg ffmpeg-devel

Note: Your rpm may be different depending on your release. You can find the correct rpm to use here: http://www.rpmfind.net/linux/rpm2html/search.php?query=rpmforge-release

- Or – Install with yum:

1. Create and add the following to /etc/yum.repos.d/dag.repo:

[dag]
name=Dag RPM Repository for Red Hat Enterprise Linux
baseurl=http://apt.sw.be/redhat/el$releasever/en/$basearch/dag
gpgcheck=1
enabled=1

2. Add the following line to /etc/ld.so.conf:

/usr/local/lib

3. Finally, execute each of the following in order:

ldconfig -v
rpm -Uvh ftp://rpmfind.net/linux/dag/redhat/el4/en/i386/dag/RPMS/rpmforge-release-0.3.6-1.el4.rf.i386.rpm
yum update
yum install ffmpeg ffmpeg-devel

Note: Your rpm may be different depending on your release You can find the correct rpm to use here: http://www.rpmfind.net/linux/rpm2html/search.php?query=rpmforge-release

You’re finished! You can find the PHP extension here: http://ffmpeg-php.sourceforge.net

I found the original yum instructions here: http://www.crucialp.com/resources/tutorials/server-administration/how-to-install-ffmpeg-centos-rhel-redhat-enterprise-easy-way.php