The ATrpms repository provides many bleeding edge software packages so if you have a development server where you install new apps this repo can be very useful. The instructions are not 100% clear about how to install this repository on CentOS Linux which would also be the same on RedHat Linux but not on Fedora Linux. Anyhow the example used on the ATrpms site relates to Fedora so the repo file needs to be modified to work on CentOS as noted below.
Recently we installed a development server running 64-Bit (x86_64) CentOS Linux. One of the things we needed to install was Python version 2.6 without overwriting the default Python version 2.4 on the server. The reason for not wanting to overwrite the default Python version is because other packages such as the Yum Package Manager depend on Python version 2.4. Anyhow in the past I have used the CHL repository for the Python version 2.6 packages because they are compiled to run as python26 or python2.6 and using the python command still launches python 2.4. Anyhow after installing the CHL yum repository as noted here we had issues installing python version 2.6 which I describe below along with how to resolve the issue.
Yum Error: Cannot retrieve repository metadata (repomd.xml) for repository: dag. Please verify its path and try again
When updating CentOS or RedHat via yum its possible to receive an error similar to the below. This error will cause an issue where yum will not work even though as described below the issue is typically isolated to one yum repository.
Error:Cannot retrieve repository metadata (repomd.xml) for repository: dag. Please verify its path and try again