2018-04-17 08:56:40,091 [INFO] {333} koji.build.buildroot:440 Running mock as kojibuilder
INFO: mock.py version 1.4.9 starting (python version = 3.6.4)...
Start: init plugins
INFO: selinux disabled
Finish: init plugins
Start: run
Start: clean chroot
Finish: clean chroot
Start: chroot init
INFO: calling preinit hooks
INFO: enabled HW Info plugin
Mock Version: 1.4.9
INFO: Mock Version: 1.4.9
Start: dnf install
ERROR: Command failed: 
 # /usr/bin/dnf --installroot /var/lib/mock/f29-build-2-16/root/ --disableplugin=local --setopt=deltarpm=False groupinstall build
Unable to detect release version (use '--releasever' to specify release version)
Last metadata expiration check: 0:02:58 ago on Tue 17 Apr 2018 08:57:43 AM UTC.
Warning: Module or Group 'build' does not exist.
Error: Nothing to do.