É o arquivo de kickstart feito pelo instalador do anaconda com base nas configurações definidas.
Há uma descrição completa do RH:
The Red Hat Enterprise Linux installation process automatically writes a Kickstart file that contains the settings for the installed system. This file is always saved as /root/anaconda-ks.cfg. You may use this file to repeat the installation with identical settings, or modify copies to specify settings for other systems.
Extraído de access.redhat.com/documentation