Mock creates chroots and builds packages in them. Its only task is to reliably populate a chroot and attempt to build a package in that chroot.
Mock is currently being used for all Fedora builds. It is called by Koji to build chroots and packages.
https://fedorahosted.org/mock/ has all the latest builds. It can be installed with "yum install mock".
To check out the current code:
git clone git://git.fedorahosted.org/git/mock.git mock
All users that are to use mock must be added to the 'mock' group.
usermod -a -G mock [User name] && newgrp mock
Configuration files are in /etc/mock. Mock versions 0.8.0 and higher cache the downloaded rpm packages (via the yum_cache plugin), which speeds up subsequent builds by a considerable margin. Nevertheless, you may wish to change the default configuration to point to local repositories to speed up builds.
By default, builds are done in /var/lib/mock, so be sure you have room. Starting with mock 0.8.0 and higher, you can change this via the 'basedir' config option.
Using Mock outside your git sandbox
Create your SRPM using 'rpmbuild -bs'. Then change to the directory where your srpm was created.
Now you can start mock with
mock -r <configname> rebuild package-1.2-3.src.rpm
where <configname> is the name of a configuration from /etc/mock/, without the /etc/mock path prefix and without the .cfg suffix.
If using mock version older than 0.8.8 or on a system with python 2.4, and building i386 packages on x86_64, prepend setarch i386 to the mock command line: setarch i386 mock -r <configfile> rebuild package-1.2-3.src.rpm. Newer versions of mock no longer need the setarch command, although it does not hurt anything if it is there.
Note that you can track the progress of mock using the logs stored in