Follow the instructions given in this page if you want to include specific custom drivers for CentOS 7 with the recommended OS for the UDP 7 Update 1 release.
To include custom drivers for Centos 8, which was made available from UDP 8.1 release, see How to Create a Bootable Live CD to Include Custom Drivers for CentOS 8.X.
Unlike the default LiveCD, UI is available when you boot the target node from LiveCD based on CentOS-7-x86_64-LiveGNOME.ISO image.
If you do not have any specific need to include custom drivers, use the default liveCD (UDP_Agent_Linux-LiveCD.iso), which is available in UDP 7 Update 1 LBS for performing BMR on a target node.
This action is applicable only for UDP 7 Update 1 for Linux release. Then, use the makelivecd.centos script available in the Linux backup server environment to create a bootable liveCD for Centos7 for any specific custom driver.
If you have a specific need to include custom drivers for performing BMR on a target node, then you need to download the CentOS-7-x86_64-LiveGNOME.ISO image from the Cent OS website (instead of CentOS-7-x86_64-LiveCD.ISO).