As you can see, the package repository cache is being updated. There is also a cleaner way to add new package repositories on Debian. On Debian operating systems, a special directory /etc/apt/sources.list.d/ is available by default. It is used to make adding new package repositories easier.

How to add a repository on your Linux machine - TechRepublic Jan 31, 2018 8.4.5. Adding, Enabling, and Disabling a Yum Repository To define a new repository, you can either add a [repository] section to the /etc/yum.conf file, or to a .repo file in the /etc/yum.repos.d/ directory. All files with the .repo file extension in this directory are read by yum, and it is recommended to define your repositories here instead of in /etc/yum.conf. How to add a Yum repository | Enable Sysadmin

Enable the EPEL Repository for EC2 Instances Running

How to add a repository on your Linux machine - TechRepublic

How to Add a Package Repository to Debian – Linux Hint

Aug 13, 2015