IUS vs. Software Collections


In 2013, Red Hat released a product called Software Collections (RHSCL). This product later got it's own community website. The front page has this statement:

Software Collections give you power to build, install, and use multiple versions of software on the same system, without affecting system-wide installed packages.

Here is our mission statement for the IUS Community project:

IUS is a community project that provides RPM packages for newer versions of select software for Enterprise Linux distributions.

Both projects seek to solve the same problem, but differ greatly in execution.

Types of Packages

File Locations


php -v
service mysqld start
mysql -V
python2.7 -V
scl enable php54 "php -v"
service mysql55-mysqld start
scl enable mysql55 "mysql -V"
scl enable python27 "python -V"


SCL in base repositories

Generally, users have to go out of their way to use SCL packages. Subscribing to a RHSCL channel or installing the centos-release-scl package are needed to access SCL packages. An exception occurred when Red Hat released MySQL SCL packages into the 5.10 base channel. While this appears to be an isolated case, it important to note this occurred and it is not clear if Red Hat will do this again. For IUS users, this created confusion as there was a mysql55 package in both the base channel and IUS repository.

More Info