Chapter 1. Red Hat Software Collections 1.1

For certain applications, more recent versions of some software components are often needed in order to use their latest new features. Red Hat Software Collections is a Red Hat offering that provides a set of dynamic programming languages, database servers, and various related packages that are either more recent than their equivalent versions included in the base Red Hat Enterprise Linux system, or are available for this system for the first time. For a complete list of components that are distributed as part of Red Hat Software Collections and a brief summary of their features, see Section 1.1, “Main Features”.
Red Hat Software Collections does not replace the default system tools provided with Red Hat Enterprise Linux 6 or Red Hat Enterprise Linux 7. Instead, a parallel set of tools is installed in the /opt directory and can be optionally enabled per application by the user using the supplied scl utility. The default versions of Perl or PostgreSQL, for example, remain those provided by the base Red Hat Enterprise Linux system.
With the notable exception of Node.js and nginx, all Red Hat Software Collections components are fully supported under Red Hat Enterprise Linux Subscription Level Agreements, are functionally complete, and are intended for production use. Important bug fixes and security errata are issued to Red Hat Software Collections subscribers in a similar manner to Red Hat Enterprise Linux for at least three years from the release of each major version. A new major version of Red Hat Software Collections is released approximately every 18 months, and in each major release stream, each version of a selected component remains backward compatible.

1.1. Main Features

Red Hat Software Collections 1.1 provides recent stable versions of the tools listed in Table 1.1, “Red Hat Software Collections 1.1 Components”.

Table 1.1. Red Hat Software Collections 1.1 Components

Component Software Collection Description
Perl 5.16.3 perl516 A release of Perl with a number of additional utilities, scripts, and database connectors for MySQL and PostgreSQL. This version provides a large number of new features and enhancements, including new debugging options, improved Unicode support, and better performance. Also, it adds perl-DateTime and mod_perl, which is supported only with the httpd24 Software Collection package.
PHP 5.4.16 php54 A release of PHP with PEAR 1.9.4 and a number of additional extensions. PHP 5.4 provides a number of language and interface improvements. The APC, memcache, and Zend OPcache extensions are also included.
PHP 5.5.6 php55 A release of PHP with enhanced language features including better exception handling, generators, and Zend OPcache. The memcache and mongodb extensions are also included.
Python 2.7.5 python27 A release of Python 2.7 with a number of additional utilities. This Python version provides various new features and enhancements, including a new ordered dictionary type, faster I/O operations, and improved forward compatibility with Python 3. The python27 Software Collections contains the Python 2.7.5 interpreter, a set of extension libraries useful for programming web applications and mod_wsgi (only supported with the httpd24 Software Collection), MySQL and PostgreSQL database connectors, and numpy and scipy.
Python 3.3.2 python33 A release of Python 3 with a number of additional utilities. This Software Collection gives developers on Red Hat Enterprise Linux access to Python 3 and allows them to benefit from various advantages and new features of this version. The python33 Software Collection contains Python 3.3.2 interpreter, a set of extension libraries useful for programming web applications and mod_wsgi (only supported with the httpd24 Software Collection), PostgreSQL database connector, and numpy and scipy.
Ruby 1.9.3[a] ruby193 A release of Ruby 1.9.3 and Ruby on Rails 3.2.8 with a large collection of Ruby gems. This Software Collection gives developers on Red Hat Enterprise Linux access to Ruby 1.9, which provides a number of new features and enhancements, including improved Unicode support, enhanced threading, faster load times, and mod_passenger, which is supported only with the httpd24 Software Collection package.
Ruby 2.0.0 ruby200 A release of Ruby 2.0.0. This version provides substantial performance and reliability improvements and includes a number of new features and improved debugging capabilities, while maintaining source level backward compatibility with Ruby 1.9.3.
Ruby on Rails 4.0.2[a] ror40 A release of Ruby on Rails 4.0, a web application development framework written in the Ruby language. This version provides a number of new features and improvements and adds live streaming for persistent connections. This Software Collection is supported together with the ruby200 collection.
MariaDB 5.5.37 mariadb55 A release of MariaDB, an alternative to MySQL for users of Red Hat Enterprise Linux. MySQL is binary compatible with MariaDB and can be replaced with it without any data conversions. This version adds the PAM authentication plugin to MariaDB.
MongoDB 2.4.9[b] mongodb24 A release of MongoDB, a cross-platform document-oriented database system classified as a NoSQL database. This Software Collection includes the mongo-java-driver package.
MySQL 5.5.37 mysql55 A release of MySQL, which provides a number of new features and enhancements, including improved performance.
PostgreSQL 9.2.8 postgresql92 A release of PostgreSQL, which provides a number of new features and enhancements, including cascading replication, native JSON support, improved scalability, and better performance.
Node.js 0.10[b][c] nodejs010 A release of Node.js with npm 1.3.24. This Software Collection gives users of Red Hat Enterprise Linux access to this programming platform.
nginx 1.4.4[d] nginx14 A release of nginx, a web and proxy server with a focus on high concurrency, performance and low memory usage.
Apache httpd 2.4.6 httpd24 A release of the Apache HTTP Server (httpd), including a high performance event-based processing model, enhanced SSL module and FastCGI support. The mod_auth_kerb module is also included.
Thermostat 1 thermostat1 A release of Thermostat, a monitoring and instrumentation tool for the OpenJDK HotSpot JVM, with support for monitoring multiple JVM instances. This Software Collection depends on the mongodb24 component.
[a] A part of this Software Collection requires a JavaScript engine. The v8314 Software Collection included in Red Hat Software Collections 1.1 provides the V8 JavaScript engine and is supported only as the Software Collection's dependency.
[b] This Software Collection also requires v8314. The v8314 Software Collection included in Red Hat Software Collections 1.1 provides the V8 JavaScript engine and is supported only as the Software Collection's dependency.
[c] In Red Hat Software Collections 1.1, Node.js is included as a Technology Preview. For more information about Red Hat Technology Previews, see https://access.redhat.com/support/offerings/techpreview/.
[d] In Red Hat Software Collections 1.1, nginx is included as a Technology Preview. For more information about Red Hat Technology Previews, see https://access.redhat.com/support/offerings/techpreview/.

1.2. Changes in Red Hat Software Collections 1.1

1.2.1. New Components

Apart from upgrading the components from Red Hat Software Collections 1.0 to later versions, which provide a number of bug fixes and enhancements over the previous versions, Red Hat Software Collections 1.1 adds these new components:
  • php55
  • ruby200
  • ror40
  • mongodb24
  • nginx14
  • httpd24
  • thermostat1
  • v8314 - the v8314 Software Collection is supported only as a dependency for the mongodb24, ruby193, ror40, and nodejs010 Software Collections.

1.2.2. New Component: Thermostat 1

The Thermostat Software Collection provides a monitoring and instrumentation tool for the OpenJDK HotSpot JVM, with support for monitoring multiple JVM instances. The system is made up of two components: an Agent, which collects data, and a Client, which allows users to visualize collected data. These components communicate via a storage layer: either directly via MongoDB or indirectly via a Web layer for increased security. A pluggable agent and GUI framework allows for collection and visualization of performance data beyond what is included out of the box.
To install the thermostat1 collection, run the following command as root: 
yum install thermostat1
To enable this collection, type the following command at a shell prompt: 
scl enable thermostat1 bash
In order to deploy the thermostat1-thermostat-webapp, that is to start the web storage endpoint in Red Hat Software Collections, use the following command: 
sudo service thermostat1-thermostat-tomcat start
For more information, please refer to the Thermostat User Guide. In order to deploy Thermostat securely, see the Configuration and Administration Guide.

1.2.3. New Component: Ruby on Rails 4.0

This Software Collection adds the ruby200 package together with the ror40 package. The Ruby on Rails collection can be enabled by the following command, which will automatically enable ruby200: 
scl enable ror40 bash
These two collections are supported together.

1.2.4. New Component: MongoDB 2.4.9

To install the mongodb24 collection, run the following command as root: 
yum install mongodb24
To run the MongoDB shell utility, type the following command: 
scl enable mongodb24 'mongo'

MongoDB 2.4.9 on Red Hat Enterprise Linux 6

If you are using Red Hat Enterprise Linux 6, the following instructions apply to your system.
To start the MongoDB daemon, type the following command: 
sudo service mongodb24-mongodb start
To start the MongoDB daemon on boot, use this command: 
sudo chkconfig mongodb24-mongodb on
To start the MongoDB sharding server, run this command: 
sudo service mongodb24-mongodb-shard start
To start the MongoDB sharding server on boot, use the following command: 
sudo chkconfig mongodb24-mongodb-shard on

MongoDB 2.4.9 on Red Hat Enterprise Linux 7

When using Red Hat Enterprise Linux 7, the following commands are applicable.
To start the MongoDB daemon, run the following command: 
sudo systemctl start mongodb24-mongodb.service
To start the MongoDB daemon on boot, use this command: 
sudo systemctl enable mongodb24-mongodb.service
To start the MongoDB sharding server, type the following command: 
sudo systemctl start mongodb24-mongodb-shard.service
To start the MongoDB sharding server on boot, run this command: 
sudo systemctl enable mongodb24-mongodb-shard.service

1.3. Compatibility Information

Red Hat Software Collections 1.1 is available for all supported releases of Red Hat Enterprise Linux 6 and Red Hat Enterprise Linux 7 on AMD64 and Intel 64 architectures.

1.4. Known Issues

nodejs-hawk component
The nodejs-hawk package uses an implementation of the SHA-1 and SHA-256 algorithms adopted from the CryptoJS project. In this release, the client-side JavaScript is obfuscated. The future fix will involve using crypto features directly from the CryptoJS library.
postgresql component
The postgresql92 package for Red Hat Enterprise Linux 6 does not provide the sepgsql module as this feature requires installation of libselinux version 2.0.99, which is not available in Red Hat Enterprise Linux 6.
python27 and python33 components
Due to a bug in the redhat-rpm-config package, it is not possible to rebuild the python27 and python33 packages on Red Hat Enterprise Linux 6.2 Extended Update Support.
coreutils component
Some utilities, for example, su, login or screen do not export environment settings in all cases, which can lead to unexpected results. It is therefore recommended to use sudo instead of su and set the env_keep environment variable in the /etc/sudoers file. Alternatively, you can run commands in a reverse order; for example: 
su -l postgres -c "scl enable postgresql92 psql"
instead of 
scl enable postgresql92 bash
su -l postgres -c psql
When using tools like screen or login, you can use the following command to preserve the environment settings: source /opt/rh/<collection_name>/enable.
httpd, mariadb, mongodb, mysql, nodejs, perl, php55, python27, python33, ruby193, ror40, ruby200, thermostat, and v8314 components
When uninstalling the httpd24, mariadb55, mongodb24, mysql55, nodejs010, perl516, php55, python27, python33, ruby193, ror40, ruby200, thermostat1, or v8314 packages, the order of uninstalling can be relevant due to ownership of dependent packages. As a consequence, some directories and files might not be removed properly and might remain on the system.
mariadb, mysql, postgresql, mongodb components
Red Hat Software Collections contains the MySQL 5.5, MariaDB 5.5, PostgreSQL 9.2 and MongoDB 2.4 databases. The core Red Hat Enterprise Linux 6 provides earlier versions of the MySQL and PostgreSQL databases (client library and daemon). The core Red Hat Enterprise Linux 7 provides the same versions of the MariaDB and PostgreSQL databases (client library and daemon). Client libraries are also used in database connectors for dynamic languages, libraries, and so on.
The client library packaged in the Red Hat Software Collections database packages in the PostgreSQL component is not supposed to be used, as it is included only for purposes of server utilities and the daemon. Users are instead expected to use the system library and the database connectors provided with the core system.
A protocol, which is used between the client library and the daemon, is stable across database versions, so, for example, using the PostgreSQL 8.4 client library with the PostgreSQL 9.2 daemon works as expected.
The core Red Hat Enterprise Linux 6 and Red Hat Enterprise Linux 7 does not include the client library for MongoDB. In order to use this client library for your application, you should use the client library from Red Hat Software Collections and always use the scl enable ... call every time you run an application linked against this MongoDB client library.
mariadb, mysql, mongodb components
MariaDB, MySQL, and MongoDB do not make use of the /opt/<provider>/<collection>/root prefix when creating log files. Note that log files are saved in the /var/log/ directory, not /opt/<provider>/<collection>/root/var/log/.
mongodb, thermostat components
The Java driver from the MongoDB collection and most of the Thermostat collection cannot be rebuilt on Red Hat Enterprise Linux 6. The following steps are necessary before rebuilding the mongodb24 or thermostat1 components on Red Hat Enterprise Linux 6 from the provided source RPM (SRPM) packages:
  1. Install the java-1.7.0-openjdk package from Red Hat Enterprise Linux 6.3 or later and all its dependencies.
  2. Download, build, and install the maven package and all its dependencies from the SRPM packages for Red Hat Enterprise Linux 7 Beta or later. For architecture-independent packages it is possible to use the binary packages provided for Red Hat Enterprise Linux 7.
  3. Download and build the main collection SRPM (mongodb24 or thermostat1).
  4. Download and build additional SRPM packages including their dependencies.
httpd component
Compiling external applications against the Apache Portable Runtime (APR) and APR-util libraries from the httpd24 Software Collection is not supported. The LD_LIBRARY_PATH is not set in httpd24 because it is not required by any application in this Software Collection.
httpd, ruby193 components
httpd is unable to execute the binary files in the mod_passenger module, namely PassengerWatchdog, PassengerHelperAgent, PassengerLoggingAgent, and SpawnPreparer in the /opt/rh/ruby193/root/usr/lib64/gems/exts/passenger-4.0.18/agents/ directory. To work around this problem, disable SELinux by running the following command as root: 
setenforce 0
nginx component
In Red Hat Enterprise Linux 6, no SELinux policy is applied for the nginx daemon.
mariadb component
The permissions for the /var/log/mariadb55-mariadb/ directory, in which the log file is stored, are set incorrectly. Consequently, when the /var/log/mariadb55-mariadb/mariadb.log file is removed in Red Hat Enterprise Linux 7, the service fails to start because the mysqld daemon does not have permission to create log files. To work around this problem, either do not remove the log file or change the owner of the /var/log/mariadb55-mariadb/ directory to mysql:mysql.
thermostat component
Thermostat applies configuration only from the USER_THERMOSTAT_HOME/etc/ssl.properties file while the THERMOSTAT_HOME/etc/ssl.properties file is ignored. Consequently, Transport Layer Security (TLS) handshakes can fail because the configuration appears to be missing. To work around this problem, specify the TLS configuration in the USER_THERMOSTAT_HOME/etc/ssl.properties file. You can copy a template from THERMOSTAT_HOME/etc/ssl.properties. Please refer to the Thermostat User Guide for differences between installation location and user data location.
thermostat component
Thermostat ignores the CONFIG_LISTEN_ADDRESS and SAVE_ON_EXIT properties in the system-wide agent.properties file. Consequently, it is impossible to configure a system-wide alternative command channel address or change Thermostat's system-wide behavior of purging its collected data on exit. To work around this problem, set the desired property in the user-specific agent properties file, USER_THERMOSTAT_HOME/etc/agent.properties.
thermostat component
The number of threads, which Thermostat uses to retrieve data from database back end, is configured incorrectly. As a consequence, the graphical client is significantly slow, especially when a large number of data is collected to display. The problem is particularly noticeable in the web back end due to network latency.
mysql, mariadb components
In Red Hat Enterprise Linux 7, the mariadb55-mariadb and mysql55-mysqld services run under the mysql user account by default. When the /var/lib/mysql/mysql.sock UNIX socket file is created by a different user, the services have insufficient permissions to check whether a process is listening on the socket but the services have sufficient permissions to delete the socket file. Consequently, the mariadb55-mariadb and mysql55-mysqld services can delete the socket file while a process is still using it.
perl component
In Red Hat Enterprise Linux 7, the perl516 Software Collection tapset conflicts with the core system tapset. As a consequence, the systemtap utility does not work correctly for perl516. To work around this problem:
  • Either copy the perl516 tapset to a file renamed by adding the Software Collection's prefix - to do so, use the following command: 
    cp /opt/rh/perl516/root/usr/share/systemtap/tapset/libperl5.16.3-64.stp /opt/rh/perl516/root/usr/share/systemtap/tapset/perl516-libperl5.16.3-64.stp
  • Or uninstall the core system perl-devel package.
python27 component
In Red Hat Enterprise Linux 7, when the user tries to install the python27-python-debuginfo package, the /usr/src/debug/Python-2.7.5/Modules/socketmodule.c file conflicts with the corresponding file from the python-debuginfo package installed on the core system. Consequently, installation of the python27-python-debuginfo fails. To work around this problem, uninstall the python-debuginfo package and then install the python27-python-debuginfo package.

Other Notes

php54 component
Note that Alternative PHP Cache (APC) in Red Hat Software Collections 1.1 is provided for user data cache only. For opcode cache, Zend OPcache is provided.
nodejs component
The nodejs-tobi-cookie package has been renamed to nodejs-cookie-jar.
ruby component
Previously, in Red Hat Software Collections 1.0, the V8 JavaScript engine was part of the ruby193 Software Collection. In Red Hat Software Collections 1.1, the v8 packages have been replaced by the v8314 Software Collection, which is installed as a dependency. In order to use therubyracer, it is necessary to enable the v8314 Software Collection as well.
nodejs component
Previously, in Red Hat Software Collections 1.0, the V8 JavaScript engine was part of the nodejs010 Software Collection. In Red Hat Software Collections 1.1, the v8 packages have been replaced by the v8314 Software Collection, which is installed as a dependency.
python component
When the user tries to install both the python27-scldevel and python33-scldevel packages, a transaction check error message is returned. This is an expected behavior because the user can install only one set of the macro files provided by the packages (%scl_python, %scl_prefix_python).
php component
When the user tries to install both the php54-scldevel and php55-scldevel packages, a transaction check error message is returned. This is an expected behavior because the user can install only one set of the macro files provided by the packages (%scl_php, %scl_prefix_php).
ruby component
When the user tries to install both the ruby193-scldevel and ruby200-scldevel packages, a transaction check error message is returned. This is an expected behavior because the user can install only one set of the macro files provided by the packages (%scl_ruby, %scl_prefix_ruby).
libyaml component
A newer version of the libyaml package is provided with Red Hat Software Collections 1.1 for use by Red Hat Software Collections.
nodejs component
When installing the nodejs010 Software Collection, nodejs010 installs GCC in the base Red Hat Enterprise Linux system as a dependency, unless the gcc packages are already installed.
mariadb component
In Red Hat Software Collections 1.1 for Red Hat Enterprise Linux 7, the mariadb55-mysqld.service file has been renamed to mariadb55-mariadb.service and the /var/log/mariadb55-mysqld.log file has been moved to /var/log/mariadb55-mariadb/mariadb55-mariadb.log, for the sake of consistency with Red Hat Enterprise Linux 7.