xCAT software and repo files can be obtained from: http://xcat.org/download.html
[xcat-core]
From the xCAT download page, find the build you want to install and add to /etc/apt/sources.list.
To configure the xCAT development build, add the following line to /etc/apt/sources.list:
deb http://xcat.org/files/xcat/repos/apt/devel/core-snap trusty main
[xcat-dep]
To configure the xCAT deps online repository, add the following line to /etc/apt/sources.list:
deb http://xcat.org/files/xcat/repos/apt/xcat-dep trusty main
If using internet repositories, continue to the next step to install xCAT.