OpenPOWER Host OS 1.0 and 1.5 used an older CentOS (7.2) as base version. To build one of them, do the following changes in this git repository before building:
Update yum repository to CentOS 7.2:
$ sed -i 's|http://mirror.centos.org/altarch/|http://vault.centos.org/altarch/7.2.1511/|' mock_configs/CentOS/7/CentOS-7-ppc64le.cfg
Update distro version to 7.2:
$ sed -i "s|distro_version:.*|distro_version: \"7.2\"|" config.yaml
$ sed -i -E "s| '7': (\"\./mock_configs.*)| '7.2': \1|" config.yaml
Update build version to v1.5.0 or v1.0.0:
$ sed -i "s|build_version:.*|build_version: \"v1.5.0\"|" config.yaml # use v1.5.0 or v1.0.0
Install rpm packages which were used in older build code, but are not anymore:
$ yum install -y bzip2 wget
Clean yum repositories cache in mock:
$ mock --scrub all
These steps are documented in https://github.com/open-power-host-os/infrastructure/tree/master/jenkins_jobs/build_old_host_os_versions/script.sh .