Repository Configuration Files

Information about package repositories is stored in configuration files, the location of which varies according to the package management tool.

RHEL compatible (yum): /etc/yum.repos.d
SLES (zypper): /etc/zypp/zypper.conf
Ubuntu (apt-get): /etc/apt/apt.conf (Additional repositories are specified using .list files in the /etc/apt/sources.list.d/ directory.)

For example, on a typical CentOS system, you might find:

ls -l /etc/yum.repos.d/
total 36
-rw-r--r--. 1 root root 1664 Dec  9  2015 CentOS-Base.repo
-rw-r--r--. 1 root root 1309 Dec  9  2015 CentOS-CR.repo
-rw-r--r--. 1 root root  649 Dec  9  2015 CentOS-Debuginfo.repo
-rw-r--r--. 1 root root  290 Dec  9  2015 CentOS-fasttrack.repo
-rw-r--r--. 1 root root  630 Dec  9  2015 CentOS-Media.repo
-rw-r--r--. 1 root root 1331 Dec  9  2015 CentOS-Sources.repo
-rw-r--r--. 1 root root 1952 Dec  9  2015 CentOS-Vault.repo
-rw-r--r--. 1 root root  951 Jun 24  2017 epel.repo
-rw-r--r--. 1 root root 1050 Jun 24  2017 epel-testing.repo

The .repo files contain pointers to one or more repositories. In the following excerpt from CentOS-Base.repo, there are two repositories defined: one named Base and one named Updates. The mirrorlist parameter points to a website that has a list of places where this repository can be downloaded.

[base]
name=CentOS-$releasever - Base
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os&infra=$infra
#baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

#released updates
[updates]
name=CentOS-$releasever - Updates
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates&infra=$infra
#baseurl=http://mirror.centos.org/centos/$releasever/updates/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7