Chapter 1. Red Hat Software Collections 2.2

This chapter serves as an overview of the Red Hat Software Collections 2.2 content set. It provides a list of components and their descriptions, sums up changes in this version, documents relevant compatibility information, and lists known issues.

1.1. About Red Hat Software Collections

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.
Red Hat Software Collections 2.2 is be available for Red Hat Enterprise Linux 7; selected new components and previously released components also for Red Hat Enterprise Linux 6. 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 1.2, “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.
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 fix and security errata are issued to Red Hat Software Collections subscribers in a similar manner to Red Hat Enterprise Linux for at least two years from the release of each major version. In each major release stream, each version of a selected component remains backward compatible. For detailed information about length of support for individual components, refer to the Red Hat Software Collections Product Life Cycle document.
Red Hat Developer Toolset is now part of Red Hat Software Collections, included as a separate Software Collection. For more information about Red Hat Developer Toolset, refer to the Red Hat Developer Toolset Release Notes and the Red Hat Developer Toolset User Guide.

1.2. Main Features

Red Hat Software Collections 2.2 provides recent stable versions of the tools listed in Table 1.1, “Red Hat Software Collections 2.2 Components”.

Table 1.1. Red Hat Software Collections 2.2 Components

Component Software Collection Description
Red Hat Developer Toolset 4.1 devtoolset-4 Red Hat Developer Toolset is designed for developers working on the Red Hat Enterprise Linux platform. It provides current versions of the GNU Compiler Collection, GNU Debugger, Eclipse development platform, and other development, debugging, and performance monitoring tools. For a complete list of components, see the Red Hat Developer Toolset Components table in the Red Hat Developer Toolset User Guide.
Perl 5.20.1 rh-perl520 A release of Perl, a high-level programming language that is commonly used for system administration utilities and web programming. The rh-perl520 Software Collection provides additional utilities, scripts, and database connectors for MySQL and PostgreSQL. Also, it includes the DateTime Perl module and the mod_perl Apache httpd module, which is supported only with the httpd24 Software Collection.
PHP 5.4.40 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 memcache and Zend OPcache extensions are also included.
PHP 5.5.21 php55 A release of PHP with PEAR 1.9.4 and enhanced language features including better exception handling, generators, and Zend OPcache. The memcache and mongodb extensions are also included.
PHP 5.6.5 rh-php56 A release of PHP with PEAR 1.9.5 and enhanced language features including constant expressions, variadic functions, arguments unpacking, and the interactive debugger. The memcache, mongo, and XDebug extensions are also included.
Python 2.7.8 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 2.7.8 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 3.4.2 rh-python34 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 rh-python34 Software Collection contains Python 3.4.2 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.
Python 3.5.1[a] rh-python35 The rh-python35 Software Collection contains Python 3.5.1 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 2.2.2 rh-ruby22 A release of Ruby 2.2. This version provides substantial performance and reliability improvements, including incremental and symbol garbage collection and many others, while maintaining source level backward compatibility with Ruby 2.0.0 and Ruby 1.9.3.
Ruby 2.3.0[a] rh-ruby23 A release of Ruby 2.3. This version introduces a command-line option to freeze all string literals in the source files, a safe navigation operator, and multiple performance enhancements, while maintaining source level backward compatibility with Ruby 2.2.2, Ruby 2.0.0, and Ruby 1.9.3.
Ruby on Rails 4.1.5 rh-ror41 A release of Ruby on Rails 4.1, a web application development framework written in the Ruby language. This version provides a number of new features including Spring application preloader, config/secrets.yml, Action Pack variants, and Action Mailer previews. This Software Collection is supported together with the rh-ruby22 Collection.
Ruby on Rails 4.2.6[a] rh-ror42 A release of Ruby on Rails 4.2, the latest version of the web application framework written in the Ruby language. Highlights in this release include Active Job, asynchronous mails, Adequate Record, Web Console, and foreign key support. This Software Collection is supported together with the rh-ruby23 and rh-nodejs4 Collections.
MariaDB 10.0.25 rh-mariadb100 A release of MariaDB, an alternative to MySQL for users of Red Hat Enterprise Linux. For all practical purposes, 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.
MariaDB 10.1.14 rh-mariadb101 A release of MariaDB, an alternative to MySQL for users of Red Hat Enterprise Linux. For all practical purposes, MySQL is binary compatible with MariaDB and can be replaced with it without any data conversions. This version adds the Galera Cluster support.
MongoDB 2.6.9 rh-mongodb26 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 version 2.14.1.
MongoDB 3.2.6[a] rh-mongodb32 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 version 3.2.1.
MongoDB 3.0.11 upgrade collection[a] rh-mongodb30upg A limited version of MongoDB 3.0 is available to provide an upgrade path from MongoDB 2.6 to MongoDB 3.2 for customers with existing MongoDB databases.
MySQL 5.6.30 rh-mysql56 A release of MySQL, which provides a number of new features and enhancements, including improved performance.
PostgreSQL 9.4.6 rh-postgresql94 A release of PostgreSQL, which provides a new data type to store JSON more efficiently and a new SQL command for changing configuration files, reduces lock strength for some commands, allows materialized views without blocking concurrent reads, supports logical decoding of WAL data to allow stream changes in a customizable format and enable background worker processes to be dynamically registered, started, and terminated.
PostgreSQL 9.5.2 rh-postgresql95 A release of PostgreSQL, which provides a number of enhancements, including row-level security control, introduces replication progress tracking, improves handling of large tables with high number of columns, and improves performance for sorting and multi-CPU machines.
Node.js 0.10 nodejs010 A release of Node.js with npm 1.4.28 and support for the SPDY protocol version 3.1. This Software Collection gives users of Red Hat Enterprise Linux access to this programming platform.
Node.js 4.4.2 rh-nodejs4 A release of Node.js with npm 2.15.1 and support for the SPDY protocol version 3.1. This Software Collection gives users of Red Hat Enterprise Linux access to this programming platform.
rh-nginx 1.8.0 rh-nginx18 A release of nginx, a web and proxy server with a focus on high concurrency, performance and low memory usage. This version introduces a number of new features, including back-end SSL certificate verification, logging to syslog, thread pools support for offloading I/O requests, or hash load balancing method.
Apache httpd 2.4.18 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.
Varnish Cache 4.0.3 rh-varnish4 A release of Varnish Cache, a high-performance HTTP reverse proxy. Varnish Cache stores files or fragments of files in memory that are used to reduce the response time and network bandwidth consumption on future equivalent requests.
Thermostat 1.4.4 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 rh-mongodb26 and rh-java-common components.
DevAssistant 0.9.3 devassist09 A release of DevAssistant, a tool designed to assist developers with creating and setting up basic projects in various programming languages, installing dependencies, setting up a development environment, and working with source control. DevAssistant supports the C, C++, Java, and Python programming languages but it is able to support working with any other language, framework, or tool due to its modular architecture.
Maven 3.0.5 maven30 A release of Maven, a software project management and comprehension tool used primarily for Java projects. Based on the concept of a project object model (POM), Maven can manage a project's build, reporting, and documentation from a central piece of information.
Maven 3.3.9[a] rh-maven33 A release of Maven, a software project management and comprehension tool used primarily for Java projects. This version provides various enhancements, for example, improved core extension mechanism.
Passenger 4.0.50 rh-passenger40 A release of Phusion Passenger, a web and application server, designed to be fast, robust, and lightweight. It supports Ruby using the ruby193, ruby200, or rh-ruby22 Software Collections together with Ruby on Rails using the ror40 or rh-ror41 Collections. It can also be used with nginx 1.6 from the nginx16 Software Collection and with Apache httpd from the httpd24 Software Collection.
Common Java Packages 1.1 rh-java-common This Software Collection provides common Java libraries and tools used by other collections. The rh-java-common Software Collection is required by the devtoolset-4, devtoolset-3, rh-maven33, maven30, rh-mongodb32, rh-mongodb26, and thermostat1 components and it is not supposed to be installed directly by users.
V8 3.14.5.10 v8314 This Software Collection provides the V8 JavaScript engine and is supported only as a dependency for the mongodb24, rh-mongodb26, rh-mongodb30upg, ruby193, ror40, rh-ror41, and nodejs010 Software Collections.
[a] This Software Collection is available only for Red Hat Enterprise Linux 7
Previously released Software Collections remain available in the same distribution channels. For example, the git19 Software Collection, which provides Git 1.9.4, has not been updated since Red Hat Software Collections 1.2 but still can be installed along with the Red Hat Software Collections 2.2 components or other previously released components.
All currently available Software Collections are listed in the Table 1.2, “All Available Software Collections”. For detailed information regarding components that have not been updated since Red Hat Software Collections 1, refer to the Red Hat Software Collections 1.2 Release Notes. See the Red Hat Software Collections Product Life Cycle document for information on the length of support for individual components.

Table 1.2. All Available Software Collections

Component Software Collection Availability
Components New in Red Hat Software Collections 2.2
MariaDB 10.1.14rh-mariadb101RHEL6, RHEL7
Maven 3.3.9rh-maven33RHEL7
MongoDB 3.0.11 upgrade collection rh-mongodb30upgRHEL7
MongoDB 3.2.6rh-mongodb32RHEL7
Node.js 4.4.2rh-nodejs4RHEL6, RHEL7
PostgreSQL 9.5.2rh-postgresql95RHEL6, RHEL7
Python 3.5.1rh-python35RHEL7
Ruby on Rails 4.2.6rh-ror42RHEL7
Ruby 2.3.0rh-ruby23RHEL7
Components Updated in Red Hat Software Collections 2.2
Red Hat Developer Toolset 4.1devtoolset-4RHEL6, RHEL7
Apache httpd 2.4.18httpd24RHEL6, RHEL7
Python 2.7.8python27RHEL6, RHEL7
Common Java Packages 1.1rh-java-commonRHEL6, RHEL7
MongoDB 2.6.9rh-mongodb26RHEL6, RHEL7
Thermostat 1.4.4thermostat1RHEL6, RHEL7
Components Not Updated since Red Hat Software Collections 2.1
Varnish Cache 4.0.3rh-varnish4RHEL6, RHEL7
nginx 1.8.0rh-nginx18RHEL6, RHEL7
Node.js 0.10nodejs010RHEL6, RHEL7
Maven 3.0.5maven30RHEL6, RHEL7
V8 3.14.5.10v8314RHEL6, RHEL7
Components Not Updated since Red Hat Software Collections 2.0
Perl 5.20.1rh-perl520RHEL6, RHEL7
PHP 5.6.5rh-php56RHEL6, RHEL7
Python 3.4.2rh-python34RHEL6, RHEL7
Ruby 2.2.2rh-ruby22RHEL6, RHEL7
Ruby on Rails 4.1.5rh-ror41RHEL6, RHEL7
MariaDB 10.0.25rh-mariadb100RHEL6, RHEL7
MySQL 5.6.30rh-mysql56RHEL6, RHEL7
PostgreSQL 9.4.6rh-postgresql94RHEL6, RHEL7
Passenger 4.0.50rh-passenger40RHEL6, RHEL7
PHP 5.4.40php54RHEL6, RHEL7
PHP 5.5.21php55RHEL6, RHEL7
nginx 1.6.2nginx16RHEL6, RHEL7
DevAssistant 0.9.3devassist09RHEL6, RHEL7
Components Not Updated since Red Hat Software Collections 1
Git 1.9.4git19RHEL6, RHEL7
Perl 5.16.3perl516RHEL6, RHEL7
Python 3.3.2python33RHEL6, RHEL7
Ruby 1.9.3ruby193RHEL6, RHEL7
Ruby 2.0.0ruby200RHEL6, RHEL7
Ruby on Rails 4.0.2ror40RHEL6, RHEL7
MariaDB 5.5.44mariadb55RHEL6, RHEL7
MongoDB 2.4.9mongodb24RHEL6, RHEL7
MySQL 5.5.45mysql55RHEL6, RHEL7
PostgreSQL 9.2.15postgresql92RHEL6, RHEL7
RHEL6 — Red Hat Enterprise Linux 6
RHEL7 — Red Hat Enterprise Linux 7
The tables above list the latest versions available through asynchronous updates.
Note that Software Collections released in Red Hat Software Collections 2.0 and later include a rh- prefix in their names.

1.3. Changes in Red Hat Software Collections 2.2

1.3.1. Overview

New Software Collections

Red Hat Software Collections 2.2 adds these new Software Collections:
Additionally, Red Hat Software Collections 2.2 includes the following new packages, which are not Software Collections but dependencies of other components:
  • gperftools — Performance Tools is a collection of performance analysis tools, including a high-performance multi-threaded malloc() implementation that works particularly well with threads and Standard Template Library (STL), a thread-friendly heap-checker, a heap profiler, and a cpu-profiler. This is a metapackage which pulls in all of the gperftools (and pprof) binaries, libraries, and development headers. Note that this package is a dependency of the rh-mongodb32 and rh-mongodb30upg Software Collections, and it is available in the Optional channel.
  • libunwind — The libunwind packages contain a C API to determine the call chain of a program. This API is necessary for compatibility with Performance Tools (gperftools). This package is a dependency of the rh-mongodb32 and rh-mongodb30upg Software Collections, and it is available in the Optional channel.

Updated Software Collections

The following components have been updated in Red Hat Software Collections 2.2:

Red Hat Software Collections Container Images

Container images based on Red Hat Software Collections 2.2 are now available, in addition to the previously released Red Hat Software Collections 2.0 container images.
The available container images include applications, daemons, and databases. The images can be run on Red Hat Enterprise Linux 7 Server and Red Hat Enterprise Linux Atomic Host. For information about their usage, see the Knowledgebase article at https://access.redhat.com/articles/1752723. For details about images based on the Red Hat Developer Toolset components, refer to the Red Hat Developer Toolset User Guide.
The following container images are new in Red Hat Software Collections 2.2:
  • rhscl/devtoolset-4-perftools-rhel7
  • rhscl/mariadb-101-rhel7
  • rhscl/mongodb-32-rhel7
  • rhscl/nginx-18-rhel7
  • rhscl/nodejs-4-rhel7
  • rhscl/postgresql-95-rhel7
  • rhscl/python-35-rhel7
  • rhscl/ror-42-rhel7
  • rhscl/ruby-23-rhel7
  • rhscl/thermostat-1-agent-rhel7
  • rhscl/varnish-4-rhel7
The following container images have been updated in Red Hat Software Collections 2.2:
  • rhscl/devtoolset-4-toolchain-rhel7
  • rhscl/httpd-24-rhel7
  • rhscl/python-27-rhel7
The following container images are based on Red Hat Software Collections 2.0:
  • rhscl/mariadb-100-rhel7
  • rhscl/mongodb-26-rhel7
  • rhscl/mysql-56-rhel7
  • rhscl/nginx-16-rhel7
  • rhscl/passenger-40-rhel7
  • rhscl/perl-520-rhel7
  • rhscl/php-56-rhel7
  • rhscl/postgresql-94-rhel7
  • rhscl/python-34-rhel7
  • rhscl/ror-41-rhel7
  • rhscl/ruby-22-rhel7
  • rhscl/s2i-base-rhel7

1.3.2. Changes in Red Hat Developer Toolset

The following components have been upgraded in Red Hat Developer Toolset 4.1 compared to the previous release of Red Hat Software Collections:
  • Eclipse to version 4.5.2
  • GCC to version 5.3.1
  • binutils to version 2.25.1
  • elfutils to version 0.166
  • GDB to version 7.11
  • SystemTap to version 2.9
  • Valgrind to version 3.11.0
  • Dyninst to version 9.1.0
For detailed information on changes in Red Hat Developer Toolset 4.1, see Red Hat Developer Toolset User Guide.

1.3.3. Changes in Python

Python 2

The python27 Software Collection has been updated to a later version, which provides a number of bug fixes and enhancements over the previous version. Among others:
  • The python27-PyYAML package has been added, which contains a Python YAML module. PyYAML is a YAML parser and emitter for Python; it is applicable for a broad range of tasks from complex configuration files to object serialization and persistance.
  • Network security enhancements, described in the Python Enhancent Proposal 466, have been backported to the Python standard library. The security enhancements include, for example, new features in the ssl module, such as support for Server Name Indication (SNI) as well as support for new TLSv1.x protocols, new hash algorithms in the hashlib module, and much more.
  • The cert-verification.cfg has been added. It contains new options that allow users to globally enable or disable SSL/TLS certificate verification in the HTTP clients (such as urllib, httplib, or xmlrpclib) of the Python standard library. The options are described in the Python Enhancement Proposal 493.
  • The python27-python-pip package has been upgraded to version 7.1.0.
  • The python27-python-virtualenv package has been upgraded to verion 13.1.0.
  • The python27-python-pymongo package has been upgraded to version 3.2.1.

Python 3

The new rh-python35 Software Collection, available for Red Hat Enterprise Linux 7, includes Python 3.5.1. This version provides a number of security fixes, bug fixes, and enhancements. Among others:
  • Security improvements
    • SSLv3 is now disabled throughout the standard library
    • HTTP cookie parsing is now stricter, to protect against potential injection attacks
  • New syntax features
    • The Python Enhancement Proposal 492 has been implemented, which greatly improves support for asynchronous programming in Python by adding awaitable objects, coroutine functions, asynchronous iteration, and asynchronous context managers
    • A new @ infix operator has been added for matrix multiplication. Matrix multiplication is a notably common operation in many fields of mathematics, science, engineering, and the addition of @ allows writing cleaner code with specialized libraries like numpy. This new operator is described in the Python Enhancement Proposal 465
  • CPython implementation improvements
    • The .pyo files are no longer used and have been replaced by a more flexible scheme that includes the optimization level explicitly in the .pyc file names; see the Python Enhancement Proposal 488 for details.
For detailed changes, see the Python 3.5.1 documentation and Python 3.5 release highlights.

1.3.4. Changes in Ruby

The new rh-ruby23 Software Collection, available for Red Hat Enterprise Linux 7, contains Ruby 2.3.0. This version provides several new features, including:
  • Safe navigation operator, also known as a lonely operator
  • Frozen String Literal Pragma
  • A new command-line option to freeze all string literals in the source files
  • A new magic comment
  • The did_you_mean gem shows the candidates on the NameError and NoMethodError exceptions to ease debugging. The did_you_mean gem is bundled.
For detailed changes, see the upstream documentation.
Ruby 2.3 is backward compatible with Ruby 2.2.2, Ruby 2.0.0, and Ruby 1.9.3. The ruby193, rh-ruby22, and ruby200 Software Collections are still available. For information about length of support for these components, refer to the Red Hat Software Collections Product Life Cycle document.
Note that the safe levels $SAFE=2 and $SAFE=3 are obsolete.

1.3.5. Changes in Ruby on Rails

Ruby on Rails 4.2.6, shipped in the new rh-ror42 Software Collection, provides the following major new features:
  • Active Job
  • Asynchronous mails
  • Adequate Record
  • Web Console
  • Foreign key support
  • GlobalID serialization
For detailed changes, see the upstream documentation.
The rh-ror42 Software Collection is supported together with the rh-ruby23 and rh-nodejs4 Collections and is available only for Red Hat Enterprise Linux 7.

1.3.6. Changes in MariaDB

The new rh-mariadb101 Software Collection includes MariaDB 10.1.14. It provides a number of bug fixes and new features, for example:
For detailed changes, refer to the upstream documentation.
For information on how to migrate to MariaDB 10.1, see Section 5.1, “Migrating to MariaDB 10.1”.

1.3.7. Changes in MongoDB

MongoDB 2.6

The rh-mongodb26 Software Collection contains the upgraded rh-mongodb26-mongo-java-driver package to the latest compatible version 2.14.1, which provides a number of bug fixes and includes support for functions from later versions of MongoDB.

MongoDB 3.0 Upgrade Collection

The new rh-mongodb30upg Collection contains a limited version of MongoDB 3.0.11 to provide an upgrade path from MongoDB 2.6 to MongoDB 3.2 for customers with existing MongoDB databases. This Software Collection includes neither MongoDB Java Driver nor MongoDB Tools and is available only for Red Hat Enterprise Linux 7.
See the Release Notes for MongoDB 3.0 for more details.

MongoDB 3.2

The new rh-mongodb32 Software Collection, available for Red Hat Enterprise Linux 7, includes MongoDB 3.2.6. It provides a number of bug fixes and new features, for example:
  • New storage engine WiredTiger, which is now default; it provides better performance and document-level locking and compression
  • Simplified data governance with document validation
  • Support for partial indexes
  • New JavaScript engine SpiderMonkey, which replaces V8
  • Increased number of replica set members
  • A new SCRAM-SHA-1 challenge-response user authentication mechanism.
Note that the mongo-java-driver package from the rh-mongodb32 Software Collection is incompatible with mongo-java-driver included in the previously released mongodb24 and rh-mongodb26 Collections. See details in the upstream documentation.
For detailed changes, refer to the Release Notes for MongoDB 3.2.
For information on how to migrate to MongoDB 3.2, see Section 5.2, “Migrating to MongoDB 3.2”.

1.3.8. Changes in PostgreSQL

The new rh-postgresql95 Software Collection includes PostgreSQL 9.5.2, which provides a number of enhancements. For example:
  • INSERT operations that would generate constraint conflicts are now allowed to be turned into UPDATE operations or ignored (UPSERT operations)
  • GROUP BY analysis features have been added: GROUPING SETS, CUBE, and ROLLUP
  • Row-level security control has been added
  • Mechanisms for tracking the progress of replication have been created, including methods for identifying the origin of individual changes during logical replication
  • Block Range Indexes (BRIN) have been added
  • Substantial performance improvements for sorting
  • Substantial performance improvements for multi-CPU machines
  • The rh-postgresql95-postgresql-static package includes the libpgport.a and libpgcommon.a libraries. These libraries are required by certain third-party packages to build, for example, by the pg_bulkload and pglogical packages.
For details, see the upstream documentation.
For information on how to migrate to PostgreSQL 9.5, see Section 5.4, “Migrating to PostgreSQL 9.5”.

1.3.9. Changes in Node.js

The new rh-nodejs4 Software Collection, includes Node.js 4.4.2. This version includes npm 2.15.1 and provides numerous security and bug fixes.
For details, see the upstream release notes and upstream documentation.
Note that the rh-nodejs4 Software Collection has been made available also for Red Hat Enterprise Linux 6 through an asynchronous update.

1.3.10. Changes in Apache httpd

The httpd24 Software Collection has been upgraded to version 2.4.18, which provides numerous bug fixes and enhancements. Notable changes are as follows:
Experimental support for the HTTP/2.0 protocol has been added, provided by the new mod_http2 module. HTTP/2 support can be enabled using the new Protocols directive. Upgrading to HTTP/2.0 over TLS is supported using the next protocol negotiation (NPN) TLS extension.
Version 7.47.1 of the curl command-line tool, with HTTP/2.0 support enabled, has been added to the Software Collection to facilitate testing.

1.3.11. Changes in Thermostat

The thermostat1 Software Collection has been upgraded to version 1.4.4, which provides numerous enhancements and bug fixes over the previous version.
  • New features:
    • A new first-run setup wizard to automatically set up credentials and related information
    • The number of threads is now always recorded
    • A new tree-map visualization for viewing the heap
    • Identification of which garbage collector is being used
    • Custom prompt for the Thermostat shell
    • Tab completion in the Thermostat shell
    • Progress display in the UI for long-running operations
    • Graphical representation for Thread deadlock
    • A new manual page for Thermostat
  • Bug fixes:
    • Various actions are now correctly disabled when the JVM they target is no longer alive
  • Security-related changes:
    • Remote Method Invocation (RMI) is no longer used in the agent
    • The command channel now runs as a separate process isolating network-facing code from everything else
  • Other improvements:
    • New helper classes in storage API for getting the oldest or newest POJOs
    • Efficiency improvements, such as implementation of fast-tail paths and querying less data when possible.
See the change log for details.

1.3.12. Changes in Maven

The new rh-maven33 Software Collection, available for Red Hat Enterprise Linux 7, includes Maven 3.3.9. This version provides numerous bug fixes and several new features. Among others:
  • Maven now requires JDK version 1.7 or later to run
  • The core extension mechanism has been improved; its usage is now simpler
  • New means of passing options to Maven and configuring JVM on per-project basis have been added
  • It is now possible to exclude all transitive dependencies using wildcards
  • Maven reactor is now pluggable.
For detailed changes, see the upstream release notes for versions 3.3.1, 3.2.1, and 3.1.1.

1.3.13. Changes in the Common Java Packages

The rh-java-common Software Collection has been updated and extended to comply with the changes in the dependent components.

1.4. Compatibility Information

Red Hat Software Collections 2.2 is available for all supported releases of Red Hat Enterprise Linux 7 on AMD64 and Intel 64 architectures. Certain components are available also for all supported releases of Red Hat Enterprise Linux 6 on AMD64 and Intel 64 architectures.
For a full list of available components, see Table 1.2, “All Available Software Collections”.

1.5. Known Issues

rh-nodejs4 component, BZ#1334856
Multiple packages from the rh-nodej4 Software Collection for Red Hat Enterprise Linux 7 are missing license information or contain incorrect license information.
python27 component, BZ#1330489
The python27-python-pymongo package has been updated to version 3.2.1 in Red Hat Software Collections 2.2. Note that this version is not fully compatible with the previously shipped version 2.5.2. For details, see https://api.mongodb.org/python/current/changelog.html.
httpd24 component, BZ#1327548
The mod_ssl module does not support the Application-Layer Protocol Negotiation (ALPN) protocol on Red Hat Enterprise Linux. Consequently, clients that support upgrading TLS connections to HTTP/2.0 only using ALPN are limited to HTTP/1.1 support. Clients that support the NPN protocol in addition to ALPN (such as Mozilla Firefox) are able to successfully upgrade to HTTP/2.0.
httpd24 component, BZ#1329639
On Red Hat Enterprise Linux 7, running the service httpd24-httpd configtest command fails with an error message. To work around this problem, run the following command: 
scl enable httpd24 'apachectl configtest'
rh-maven33 component
When the user has installed both the Red Hat Enterprise Linux system version of maven-local package and the rh-maven33-maven-local package, XMvn, a tool used for building Java RPM packages, run from the rh-maven33 Software Collection tries to read the configuration file from the base system and fails. To work around this problem, uninstall the maven-local package from the base Red Hat Enterprise Linux system.
rh-nodejs4 component, BZ#1316626
The /opt/rh/rh-nodejs4/root/usr/share/licenses/ directory is not owned by any package. Consequently, when the rh-nodejs4 collection is uninstalled, this directory is not removed. To work around this problem, remove the directory manually after uninstalling rh-nodejs4.
rh-mysql56, rh-mariadb100, rh-mariadb101 components, BZ#1194611
The rh-mysql56-mysql-server, rh-mariadb100-mariadb-server, and rh-mariadb101-mariadb-server packages no longer provide the test database by default. Although this database is not created during initialization, the grant tables are prefilled with the same values as when test was created by default. As a consequence, upon a later creation of the test or test_* databases, these databases have less restricted access rights than is default for new databases.
Additionally, when running benchmarks, the run-all-tests script no longer works out of the box with example parameters. You need to create a test database before running the tests and specify the database name in the --database parameter. If the parameter is not specified, test is taken by default but you need to make sure the test database exist.
httpd24 component, BZ#1224763
When using the mod_proxy_fcgi module with FastCGI Process Manager (PHP-FPM), httpd uses port 8000 for the FastCGI protocol by default instead of the correct port 9000. To work around this problem, specify the correct port explicitly in configuration.
rh-passenger40 component, BZ#1196555
When Passenger from the rh-passenger40 Software Collection is run as a module for httpd, the functionality is restricted by SELinux policy. To work around this problem, switch the passenger domain to permissive mode by running the following command as root: 
semanage permissive -a passenger_t
Standalone server and nginx integration are not affected by this issue.
mongodb24 component
The mongodb24 Software Collection from Red Hat Software Collections 1.2 cannot be rebuilt with the rh-java-common and maven30 Software Collections shipped with Red Hat Software Collections 2.2. Additionally, the mongodb24-build and mongodb24-scldevel packages cannot be installed with Red Hat Software Collections 2.2 due to unsatisfied requires on the maven30-javapackages-tools and maven30-maven-local packages. When the mongodb24-scldevel package is installed, broken dependencies are reported and the yum --skip-broken command skips too many packages. Users are advised to update to the rh-mongodb26 Software Collection.
perl component
When the user tries to use the mod_perl module from both the rh-perl520 and perl516 Software Collections, a conflict in the /opt/rh/httpd24/root/usr/lib64/httpd/modules/mod_perl.so file occurs. As a consequence, it is impossible to use mod_perl from more than one Perl Software Collection.
nodejs010 component
Shared libraries provided by the nodejs010 Software Collection, namely libcares, libhttp_parser, and libuv, are not properly prefixed with the Collection name. As a consequence, conflicts with the corresponding system libraries might occur.
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, rh-postgresql94, and rh-postgresql95 packages for Red Hat Enterprise Linux 6 do 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.
httpd, mariadb, mongodb, mysql, nodejs, perl, php55, rh-php56, python, ruby, ror, thermostat, and v8314 components, BZ#1072319
When uninstalling the httpd24, mariadb55, rh-mariadb100, mongodb24, rh-mongodb26, mysql55, rh-mysql56, nodejs010, perl516, rh-perl520, php55, rh-php56, python27, python33, rh-python34, ruby193, ruby200, rh-ruby22, ror40, rh-ror41, 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 2.2 contains the MySQL 5.6, MariaDB 10.0, MariaDB 10.1, PostgreSQL 9.4, PostgreSQL 9.5, MongoDB 2.6, and MongoDB 3.2 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 earlier 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 9.2 client library with the PostgreSQL 9.4 or 9.5 daemon works as expected.
The core Red Hat Enterprise Linux 6 and Red Hat Enterprise Linux 7 do 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/opt/provider/collection/log/ directory, not in /opt/provider/collection/root/var/log/.
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 environment variable is not set in httpd24 because it is not required by any application in this Software Collection.
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.
devassist component
When the user tries to rebuild the devassist09-PyYAML package on Red Hat Enterprise Linux 6, the build fails due to a soft dependency, if the Pyrex or Cython programming languages are detected. To work around this problem, make sure the pyrex or cython packages are not installed on your system.

Other Notes

rh-ruby22, rh-python34, rh-php56 components
Using Software Collections on a read-only NFS has several limitations.
  • Ruby gems cannot be installed while the rh-ruby22 Software Collection is on a read-only NFS. Consequently, for example, when the user tries to install the ab gem using the gem install ab command, the following error message is displayed: 
    ERROR:  While executing gem ... (Errno::EROFS)
    Read-only file system @ dir_s_mkdir - /opt/rh/rh-ruby22/root/usr/local/share/gems
    The same problem occurs when the user tries to update or install gems from an external source by running the bundle update or bundle install commands.
  • When installing Python packages on a read-only NFS using the Python Package Index (PyPI), running the pip command fails with an error message similar to this: 
    Read-only file system: '/opt/rh/rh-python34/root/usr/lib/python3.4/site-packages/ipython-3.1.0.dist-info'
  • Installing packages from PHP Extension and Application Repository (PEAR) on a read-only NFS using the pear command fails with the error message: 
    Cannot install, php_dir for channel "pear.php.net" is not writeable by the current user
This is an expected behavior.
thermostat component
The thermostat1-thermostat-tomcat start command, which starts the Thermostat web storage endpoint, can be used only on Red Hat Enterprise Linux 6 and Red Hat Enterprise Linux 7.0. On Red Hat Enterprise Linux 7.1 and later versions, use service tomcat@thermostat start instead.
httpd component
Language modules for Apache are supported only with the Red Hat Software Collections version of Apache httpd and not with the Red Hat Enterprise Linux system versions of httpd. For example, the mod_wsgi module from the rh-python34 Collection can be used only with the httpd24 Collection.
all components
Since Red Hat Software Collections 2.0, configuration files, variable data, and runtime data of individual Collections are stored in different directories than in previous versions of Red Hat Software Collections.
coreutils, util-linux, screen components
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 rh-postgresql94 psql"
instead of 
scl enable rh-postgresql94 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
php54 component
Note that Alternative PHP Cache (APC) in Red Hat Software Collections is provided only for user data cache. For opcode cache, Zend OPcache is provided.
python component
When the user tries to install more than one scldevel package from the python27, python33, and rh-python34 Software Collections, 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 more than one scldevel package from the php54, php55, and rh-php56 Software Collections, 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 more than one scldevel package from the ruby193, ruby200, and rh-ruby22 Software Collections, 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).
perl component
When the user tries to install more than one scldevel package from the perl516 and rh-perl520 Software Collections, 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_perl, %scl_prefix_perl).
nginx component
When the user tries to install more than one scldevel package from the nginx16 and rh-nginx18 Software Collections, 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_nginx, %scl_prefix_nginx).
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.