Chapter 1. Red Hat Software Collections 3.4

This chapter serves as an overview of the Red Hat Software Collections 3.4 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 3.4 is available for Red Hat Enterprise Linux 7; selected 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.

Note

In Red Hat Enterprise Linux 8, similar components are provided as Application Streams.
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.

1.1.1. Red Hat Developer Toolset

Red Hat Developer Toolset is a 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

Table 1.1, “Red Hat Software Collections 3.4 Components” lists components that are supported at the time of the Red Hat Software Collections 3.4 release.

Table 1.1. Red Hat Software Collections 3.4 Components

Component Software Collection Description
Red Hat Developer Toolset 9.0 devtoolset-9 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, 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 5.26.3[a] rh-perl526 A release of Perl, a high-level programming language that is commonly used for system administration utilities and web programming. The rh-perl526 Software Collection provides additional utilities, scripts, and database connectors for MySQL and PostgreSQL. It includes the DateTime Perl module and the mod_perl Apache httpd module, which is supported only with the httpd24 Software Collection. Additionally, it provides the cpanm utility for easy installation of CPAN modules. The rh-perl526 packaging is aligned with upstream; the perl526-perl package installs also core modules, while the interpreter is provided by the perl-interpreter package.
PHP 7.2.24 [a] rh-php72 A release of PHP 7.2 with PEAR 1.10.5, APCu 5.1.12, and enhanced language features.
PHP 7.3.11 [a] rh-php73 A release of PHP 7.3 with PEAR 1.10.9, APCu 5.1.17, and the Xdebug extension.
Python 2.7.16 python27 A release of Python 2.7 with a number of additional utilities. This Python version provides various features and enhancements, including an ordered dictionary type, faster I/O operations, and improved forward compatibility with Python 3. The python27 Software Collections contains the Python 2.7.13 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 3.6.9 rh-python36 The rh-python36 Software Collection contains Python 3.6.9, which introduces a number of new features, such as f-strings, syntax for variable annotations, and asynchronous generators and comprehensions. In addition, a set of extension libraries useful for programming web applications is included, with mod_wsgi (supported only together with the httpd24 Software Collection), PostgreSQL database connector, and numpy and scipy.
Ruby 2.4.6 rh-ruby24 A release of Ruby 2.4. This version provides multiple performance improvements and enhancements, for example improved hash table, new debugging features, support for Unicode case mappings, and support for OpenSSL 1.1.0. Ruby 2.4.0 maintains source-level backward compatibility with Ruby 2.3, Ruby 2.2, Ruby 2.0.0, and Ruby 1.9.3.
Ruby 2.5.5 [a] rh-ruby25 A release of Ruby 2.5. This version provides multiple performance improvements and new features, for example, simplified usage of blocks with the rescue, else, and ensure keywords, a new yield_self method, support for branch coverage and method coverage measurement, new Hash#slice and Hash#transform_keys methods. Ruby 2.5.0 maintains source-level backward compatibility with Ruby 2.4.
Ruby 2.6.2 [a] rh-ruby26 A release of Ruby 2.6. This version provides multiple performance improvements and new features, such as endless ranges, the Binding#source_location method, and the $SAFE process global state. Ruby 2.6.0 maintains source-level backward compatibility with Ruby 2.5.
Ruby on Rails 5.0.1 rh-ror50 A release of Ruby on Rails 5.0, the latest version of the web application framework written in the Ruby language. Notable new features include Action Cable, API mode, exclusive use of rails CLI over Rake, and ActionRecord attributes. This Software Collection is supported together with the rh-ruby24 Collection.
Scala 2.10.6 [a] rh-scala210 A release of Scala, a general purpose programming language for the Java platform, which integrates features of object-oriented and functional languages.
MariaDB 10.2.22 rh-mariadb102 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 MariaDB Backup, Flashback, support for Recursive Common Table Expressions, window functions, and JSON functions.
MariaDB 10.3.13 [a] rh-mariadb103 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 introduces system-versioned tables, invisible columns, a new instant ADD COLUMN operation for InnoDB, and a JDBC connector for MariaDB and MySQL.
MongoDB 3.4.9 rh-mongodb34 A release of MongoDB, a cross-platform document-oriented database system classified as a NoSQL database. This release introduces support for new architectures, adds message compression and support for the decimal128 type, enhances collation features and more.
MongoDB 3.6.3 [a] rh-mongodb36 A release of MongoDB, a cross-platform document-oriented database system classified as a NoSQL database. This release introduces change streams, retryable writes, and JSON Schema, as well as other features.
MySQL 8.0.17 [a] rh-mysql80 A release of the MySQL server, which introduces a number of new security and account management features and enhancements.
PostgreSQL 9.6.10 rh-postgresql96 A release of PostgreSQL, which introduces parallel execution of sequential scans, joins, and aggregates, and provides enhancements to synchronous replication, full-text search, deration driver, postgres_fdw, as well as performance improvements.
PostgreSQL 10.6 [a] rh-postgresql10 A release of PostgreSQL, which includes a significant performance improvement and a number of new features, such as logical replication using the publish and subscribe keywords, or stronger password authentication based on the SCRAM-SHA-256 mechanism.
PostgreSQL 12.1 [a] rh-postgresql12 A release of PostgreSQL, which provides the pgaudit extension, various enhancements to partitioning and parallelism, support for the SQL/JSON path language, and performance improvements.
Node.js 10.16.3 [a] rh-nodejs10 A release of Node.js, which provides multiple API enhancements and new features, including V8 engine version 6.6, full N-API support, and stability improvements.
Node.js 12.10.0 [a] rh-nodejs12 A release of Node.js, with V8 engine version 7.6, support for ES6 modules, and improved support for native modules.
nginx 1.10.2 rh-nginx110 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 dynamic module support, HTTP/2 support, Perl integration, and numerous performance improvements.
nginx 1.14.1 [a] rh-nginx114 A release of nginx, a web and proxy server with a focus on high concurrency, performance, and low memory usage. This version provides a number of features, such as mirror module, HTTP/2 server push, gRPC proxy module, and numerous performance improvements.
nginx 1.16.1 [a] rh-nginx116 A release of nginx, a web and proxy server with a focus on high concurrency, performance, and low memory usage. This version introduces numerous updates related to SSL, several new directives and parameters, and various enhancements.
Apache httpd 2.4.34 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, mod_auth_mellon, and ModSecurity modules are also included.
Varnish Cache 5.2.1 [a] rh-varnish5 A release of Varnish Cache, a high-performance HTTP reverse proxy. This version includes the shard director, experimental HTTP/2 support, and improvements to Varnish configuration through separate VCL files and VCL labels.
Varnish Cache 6.0.2 [a] rh-varnish6 A release of Varnish Cache, a high-performance HTTP reverse proxy. This version includes support for Unix Domain Sockets (both for clients and for back-end servers), new level of the VCL language (vcl 4.1), and improved HTTP/2 support.
Maven 3.5.0 [a] rh-maven35 A release of Maven, a software project management and comprehension tool. This release introduces support for new architectures and a number of new features, including colorized logging.
Maven 3.6.1 [a] rh-maven36 A release of Maven, a software project management and comprehension tool. This release provides various enhancements and bug fixes.
Git 2.18.1 [a] rh-git218 A release of Git, a distributed revision control system with a decentralized architecture. As opposed to centralized version control systems with a client-server model, Git ensures that each working copy of a Git repository is its exact copy with complete revision history. This version includes the Large File Storage (LFS) extension.
Redis 5.0.5 [a] rh-redis5 A release of Redis 5.0, a persistent key-value database. Redis now provides redis-trib, a cluster management tool.
HAProxy 1.8.17 [a] rh-haproxy18 A release of HAProxy 1.8, a reliable, high-performance network load balancer for TCP and HTTP-based applications.
Common Java Packages 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 rh-maven35 and rh-scala210 components and it is not supposed to be installed directly by users.
JDK Mission Control [a] rh-jmc This Software Collection includes JDK Mission Control (JMC), a powerful profiler for HotSpot JVMs. JMC provides an advanced set of tools for efficient and detailed analysis of extensive data collected by the JDK Flight Recorder. JMC requires JDK version 8 or later to run. Target Java applications must run with at least OpenJDK version 11 so that JMC can access JDK Flight Recorder features. The rh-jmc Software Collection requires the rh-maven35 Software Collection.
[a] This Software Collection is available only for Red Hat Enterprise Linux 7
Previously released Software Collections remain available in the same distribution channels. All Software Collections, including retired components, are listed in the Table 1.2, “All Available Software Collections”. Software Collections that are no longer supported are marked with an asterisk (*).
See the Red Hat Software Collections Product Life Cycle document for information on the length of support for individual components. For detailed information regarding previously released components, refer to the Release Notes for earlier versions of Red Hat Software Collections.

Table 1.2. All Available Software Collections

Component Software Collection Availability Architectures supported on RHEL7
Components New in Red Hat Software Collections 3.4
Red Hat Developer Toolset 9.0devtoolset-9RHEL7x86_64, s390x, aarch64, ppc64, ppc64le
Node.js 12.10.0rh-nodejs12RHEL7x86_64, s390x, aarch64, ppc64le
PHP 7.3.11rh-php73RHEL7x86_64, s390x, aarch64, ppc64le
nginx 1.16.1rh-nginx116RHEL7x86_64, s390x, aarch64, ppc64le
PostgreSQL 12.1rh-postgresql12RHEL7x86_64, s390x, aarch64, ppc64le
Maven 3.6.1rh-maven36RHEL7x86_64, s390x, aarch64, ppc64le
Components Updated in Red Hat Software Collections 3.4
Apache httpd 2.4.34httpd24RHEL6, RHEL7x86_64, s390x, aarch64, ppc64le
Components Last Updated in Red Hat Software Collections 3.3
Red Hat Developer Toolset 8.1devtoolset-8RHEL6, RHEL7x86_64, s390x, aarch64, ppc64, ppc64le
MariaDB 10.3.13rh-mariadb103RHEL7x86_64, s390x, aarch64, ppc64le
Redis 5.0.5rh-redis5RHEL7x86_64, s390x, aarch64, ppc64le
Ruby 2.6.2rh-ruby26RHEL7x86_64, s390x, aarch64, ppc64le
HAProxy 1.8.17rh-haproxy18RHEL7x86_64
Varnish Cache 6.0.2rh-varnish6RHEL7x86_64, s390x, aarch64, ppc64le
Components Last Updated in Red Hat Software Collections 3.2
PHP 7.2.24rh-php72RHEL7x86_64, s390x, aarch64, ppc64le
MySQL 8.0.17rh-mysql80RHEL7x86_64, s390x, aarch64, ppc64le
Node.js 10.16.3rh-nodejs10RHEL7x86_64, s390x, aarch64, ppc64le
nginx 1.14.1rh-nginx114RHEL7x86_64, s390x, aarch64, ppc64le
Git 2.18.1rh-git218RHEL7x86_64, s390x, aarch64, ppc64le
JDK Mission Controlrh-jmcRHEL7x86_64
Components Last Updated in Red Hat Software Collections 3.1
Red Hat Developer Toolset 7.1devtoolset-7*RHEL6, RHEL7x86_64, s390x, aarch64, ppc64, ppc64le
Perl 5.26.3rh-perl526RHEL7x86_64, s390x, aarch64, ppc64le
Ruby 2.5.5rh-ruby25RHEL7x86_64, s390x, aarch64, ppc64le
MongoDB 3.6.3rh-mongodb36RHEL7x86_64, s390x, aarch64, ppc64le
Varnish Cache 5.2.1rh-varnish5RHEL7x86_64, s390x, aarch64, ppc64le
PostgreSQL 10.6rh-postgresql10RHEL7x86_64, s390x, aarch64, ppc64le
PHP 7.0.27rh-php70*RHEL6, RHEL7x86_64
MySQL 5.7.24rh-mysql57*RHEL6, RHEL7x86_64, s390x, aarch64, ppc64le
Components Last Updated in Red Hat Software Collections 3.0
PHP 7.1.8rh-php71*RHEL7x86_64, s390x, aarch64, ppc64le
nginx 1.12.1rh-nginx112*RHEL7x86_64, s390x, aarch64, ppc64le
Python 3.6.9rh-python36RHEL6, RHEL7x86_64, s390x, aarch64, ppc64le
Maven 3.5.0rh-maven35RHEL7x86_64, s390x, aarch64, ppc64le
MariaDB 10.2.22rh-mariadb102RHEL6, RHEL7x86_64, s390x, aarch64, ppc64le
PostgreSQL 9.6.10rh-postgresql96RHEL6, RHEL7x86_64, s390x, aarch64, ppc64le
MongoDB 3.4.9rh-mongodb34RHEL6, RHEL7x86_64, s390x, aarch64, ppc64le
Node.js 8.11.4rh-nodejs8*RHEL7x86_64, s390x, aarch64, ppc64le
Components Last Updated in Red Hat Software Collections 2.4
Red Hat Developer Toolset 6.1devtoolset-6*RHEL6, RHEL7x86_64, s390x, aarch64, ppc64, ppc64le
Scala 2.10.6rh-scala210RHEL7x86_64
nginx 1.10.2rh-nginx110RHEL6, RHEL7x86_64
Node.js 6.11.3rh-nodejs6*RHEL6, RHEL7x86_64, s390x, aarch64, ppc64le
Ruby 2.4.6rh-ruby24RHEL6, RHEL7x86_64
Ruby on Rails 5.0.1rh-ror50RHEL6, RHEL7x86_64
Eclipse 4.6.3rh-eclipse46*RHEL7x86_64
Python 2.7.16python27RHEL6, RHEL7x86_64, s390x, aarch64, ppc64le
Thermostat 1.6.6rh-thermostat16*RHEL6, RHEL7x86_64
Maven 3.3.9rh-maven33*RHEL6, RHEL7x86_64
Common Java Packagesrh-java-commonRHEL6, RHEL7x86_64
Components Last Updated in Red Hat Software Collections 2.3
Git 2.9.3rh-git29*RHEL6, RHEL7x86_64, s390x, aarch64, ppc64le
Redis 3.2.4rh-redis32*RHEL6, RHEL7x86_64
Perl 5.24.0rh-perl524*RHEL6, RHEL7x86_64
Python 3.5.1rh-python35*RHEL6, RHEL7x86_64
MongoDB 3.2.10rh-mongodb32*RHEL6, RHEL7x86_64
Ruby 2.3.8rh-ruby23*RHEL6, RHEL7x86_64
PHP 5.6.25rh-php56*RHEL6, RHEL7x86_64
Components Last Updated in Red Hat Software Collections 2.2
Red Hat Developer Toolset 4.1devtoolset-4*RHEL6, RHEL7x86_64
MariaDB 10.1.29rh-mariadb101*RHEL6, RHEL7x86_64
MongoDB 3.0.11 upgrade collection rh-mongodb30upg*RHEL6, RHEL7x86_64
Node.js 4.6.2rh-nodejs4*RHEL6, RHEL7x86_64
PostgreSQL 9.5.14rh-postgresql95*RHEL6, RHEL7x86_64
Ruby on Rails 4.2.6rh-ror42*RHEL6, RHEL7x86_64
MongoDB 2.6.9rh-mongodb26*RHEL6, RHEL7x86_64
Thermostat 1.4.4thermostat1*RHEL6, RHEL7x86_64
Components Last Updated in Red Hat Software Collections 2.1
Varnish Cache 4.0.3rh-varnish4*RHEL6, RHEL7x86_64
nginx 1.8.1rh-nginx18*RHEL6, RHEL7x86_64
Node.js 0.10nodejs010*RHEL6, RHEL7x86_64
Maven 3.0.5maven30*RHEL6, RHEL7x86_64
V8 3.14.5.10v8314*RHEL6, RHEL7x86_64
Components Last Updated in Red Hat Software Collections 2.0
Red Hat Developer Toolset 3.1devtoolset-3*RHEL6, RHEL7x86_64
Perl 5.20.1rh-perl520*RHEL6, RHEL7x86_64
Python 3.4.2rh-python34*RHEL6, RHEL7x86_64
Ruby 2.2.9rh-ruby22*RHEL6, RHEL7x86_64
Ruby on Rails 4.1.5rh-ror41*RHEL6, RHEL7x86_64
MariaDB 10.0.33rh-mariadb100*RHEL6, RHEL7x86_64
MySQL 5.6.40rh-mysql56*RHEL6, RHEL7x86_64
PostgreSQL 9.4.14rh-postgresql94*RHEL6, RHEL7x86_64
Passenger 4.0.50rh-passenger40*RHEL6, RHEL7x86_64
PHP 5.4.40php54*RHEL6, RHEL7x86_64
PHP 5.5.21php55*RHEL6, RHEL7x86_64
nginx 1.6.2nginx16*RHEL6, RHEL7x86_64
DevAssistant 0.9.3devassist09*RHEL6, RHEL7x86_64
Components Last Updated in Red Hat Software Collections 1
Git 1.9.4git19*RHEL6, RHEL7x86_64
Perl 5.16.3perl516*RHEL6, RHEL7x86_64
Python 3.3.2python33*RHEL6, RHEL7x86_64
Ruby 1.9.3ruby193*RHEL6, RHEL7x86_64
Ruby 2.0.0ruby200*RHEL6, RHEL7x86_64
Ruby on Rails 4.0.2ror40*RHEL6, RHEL7x86_64
MariaDB 5.5.53mariadb55*RHEL6, RHEL7x86_64
MongoDB 2.4.9mongodb24*RHEL6, RHEL7x86_64
MySQL 5.5.52mysql55*RHEL6, RHEL7x86_64
PostgreSQL 9.2.18postgresql92*RHEL6, RHEL7x86_64
Legend:
  • RHEL6 – Red Hat Enterprise Linux 6
  • RHEL7 – Red Hat Enterprise Linux 7
  • x86_64 – AMD64 and Intel 64 architectures
  • s390x – IBM Z
  • aarch64 – The 64-bit ARM architecture
  • ppc64 – IBM POWER, big endian
  • ppc64le – IBM POWER, little endian
  • * – Retired component; this Software Collection is no longer supported
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.
Eclipse is available as a part of the Red Hat Developer Tools offering.

1.3. Changes in Red Hat Software Collections 3.4

1.3.1. Overview

Architectures

The Red Hat Software Collections offering contains packages for Red Hat Enterprise Linux 7 running on AMD64 and Intel 64 architectures; certain earlier Software Collections are available also for Red Hat Enterprise Linux 6.
In addition, Red Hat Software Collections 3.4 supports the following architectures on Red Hat Enterprise Linux 7:
  • The 64-bit ARM architecture
  • IBM Z
  • IBM POWER, little endian
For a full list of components and their availability, see Table 1.2, “All Available Software Collections”.

New Software Collections

Red Hat Software Collections 3.4 adds the following new Software Collections:
All new Software Collections are available only for Red Hat Enterprise Linux 7.

Updated Software Collections

The following component has been updated in Red Hat Software Collections 3.4:

Red Hat Software Collections Container Images

The following container images are new in Red Hat Software Collections 3.4:
  • rhscl/devtoolset-9-toolchain-rhel7
  • rhscl/devtoolset-9-perftools-rhel7
  • rhscl/nodejs-12-rhel7
  • rhscl/php-73-rhel7
  • rhscl/nginx-116-rhel7
  • rhscl/postgresql-12-rhel7
The following container image has been updated in Red Hat Software Collections 3.4:
  • rhscl/httpd-24-rhel7
For detailed information regarding Red Hat Software Collections container images, see Section 3.4, “Red Hat Software Collections Container Images”.

1.3.2. Changes in Red Hat Developer Toolset

The following components have been upgraded in Red Hat Developer Toolset 9.0 compared to the previous release of Red Hat Developer Toolset:
  • GCC to version 9.1.1
  • binutils to version 2.32
  • GDB to version 8.3
  • strace to version 5.1
  • SystemTap to version 4.1
  • Valgrind to version 3.15.0
  • Dyninst to version 10.1.0
For detailed information on changes in 9.0, see the Red Hat Developer Toolset User Guide.

1.3.3. Changes in Node.js

The new rh-nodejs12 Software Collection provides Node.js 12.10.0. Notable enhancements in this release include:
  • The V8 engine upgraded to version 7.6
  • A new default HTTP parser, llhttp (no longer experimental)
  • Integrated capability of heap dump generation
  • Support for ECMAScript 2015 (ES6) modules
  • Improved support for native modules
  • Worker threads no longer require a flag
  • A new experimental diagnostic report feature
  • Improved performance
For detailed changes in Node.js 12.10.0, see the upstream release notes and upstream documentation.

1.3.4. Changes in PHP

The new rh-php73 Software Collection with PHP 7.3.11 introduces the following notable enhancements over rh-php72:
  • The Xdebug extension included for development
  • Enhanced and more flexible heredoc and nowdoc syntaxes
  • The PCRE extension upgraded to PCRE2
  • Improved multibyte string handling
  • Support for LDAP controls
  • Improved FastCGI Process Manager (FPM) logging
  • The ability to add a trailing comma in function calls
  • Improved performance
  • Several deprecations and backward incompatible changes
For more information, see Migrating from PHP 7.2.x to PHP 7.3.x.
Note that the following behavior is different from upstream:
  • The rh-php73 Software Collection does not support the Argon2 password hashing algorithm.
  • The x (PCRE_EXTENDED) pattern modifier is always enabled in the rh-php73 Software Collection. As a result, invalid escape sequences are not interpreted as literals.

1.3.5. Changes in nginx

The new rh-nginx116 Software Collection provides nginx 1.16.1, which introduces a number of new features and enhancements. For example:
  • Numerous updates related to SSL (loading of SSL certificates and secret keys from variables, variable support in the ssl_certificate and ssl_certificate_key directives, a new ssl_early_data directive)
  • New keepalive-related directives
  • A new random directive for distributed load balancing
  • New parameters and improvements to existing directives (port ranges for the listen directive, a new delay parameter for the limit_req directive, which enables two-stage rate limiting)
  • A new $upstream_bytes_sent variable
  • Improvements to User Datagram Protocol (UDP) proxying
Other notable changes include:
  • The ssl directive has been deprecated; use the ssl parameter for the listen directive instead.
  • nginx now detects missing SSL certificates during configuration testing.
  • When using a host name in the listen directive, nginx now creates listening sockets for all addresses that the host name resolves to.
For more information regarding changes in nginx, refer to the upstream release notes.
For migration instructions, see Section 5.8, “Migrating to nginx 1.16”.

1.3.6. Changes in PostgreSQL

The new rh-postgresql12 Software Collection includes PostgreSQL 12.1. This release introduces various enhancements over version 10, distributed in an earlier Software Collection, such as:
  • The PostgreSQL Audit Extension, pgaudit, which provides detailed session and object audit logging through the standard PostgreSQL logging facility.
  • Improvements to the partitioning functionality, for example, support for hash partitioning
  • Enhancements to query parallelism
  • Stored SQL procedures enabling transaction management
  • Various performance improvements
  • Enhancements to the administrative functionality
  • Support for the SQL/JSON path language
  • Stored generated columns
  • Nondeterministic collations
  • New authentication features, including encryption of TCP/IP connections when using GSSAPI authentication or multi-factor authentication.
For detailed changes, see the upstream release notes for PostgreSQL 11 and PostgreSQL 12.
Note that support for Just-In-Time (JIT) compilation, available in upstream since PostgreSQL 11, is not provided by the rh-postgresql12 Software Collection.
The rh-postgresql12 Software Collection includes the rh-postgresql12-syspaths package, which installs packages that provide system-wide wrappers for binaries, scripts, manual pages, and others. After installing the rh-postgreqsl12*-syspaths packages, users are not required to use the scl enable command for correct functioning of the binaries and scripts provided by the rh-postgreqsl12* packages. Note that the *-syspaths packages conflict with the corresponding packages from the base Red Hat Enterprise Linux system. To find out more about syspaths, see the Red Hat Software Collections Packaging Guide.
For information on migration, see Section 5.6, “Migrating to PostgreSQL 12”.

1.3.7. Changes in Maven

The new rh-maven36 Software Collection with Maven 3.6.1 includes numerous bug fixes and various enhancements. For detailed changes, see the upstream release notes.

1.3.8. Changes in Apache httpd

The httpd24 Software Collection has been updated to provide several security and bug fixes.

1.4. Compatibility Information

Red Hat Software Collections 3.4 is available for all supported releases of Red Hat Enterprise Linux 7 on AMD64 and Intel 64 architectures, the 64-bit ARM architecture, IBM Z, and IBM POWER, little endian.
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

multiple components, BZ#1716378
Certain files provided by the Software Collections debuginfo packages might conflict with the corresponding debuginfo package files from the base Red Hat Enterprise Linux system or from other versions of Red Hat Software Collections components. For example, the python27-python-debuginfo package files might conflict with the corresponding files from the python-debuginfo package installed on the core system. Similarly, files from the httpd24-mod_auth_mellon-debuginfo package might conflict with similar files provided by the base system mod_auth_mellon-debuginfo package. To work around this problem, uninstall the base system debuginfo package prior to installing the Software Collection debuginfo package.
rh-mysql80 component, BZ#1646363
The mysql-connector-java database connector does not work with the MySQL 8.0 server. To work around this problem, use the mariadb-java-client database connector from the rh-mariadb103 Software Collection.
rh-mysql80 component, BZ#1646158
The default character set has been changed to utf8mb4 in MySQL 8.0 but this character set is unsupported by the php-mysqlnd database connector. Consequently, php-mysqlnd fails to connect in the default configuration. To work around this problem, specify a known character set as a parameter of the MySQL server configuration. For example, modify the /etc/opt/rh/rh-mysql80/my.cnf.d/mysql-server.cnf file to read: 
[mysqld]
character-set-server=utf8
httpd24 component, BZ#1429006
Since httpd 2.4.27, the mod_http2 module is no longer supported with the default prefork Multi-Processing Module (MPM). To enable HTTP/2 support, edit the configuration file at /opt/rh/httpd24/root/etc/httpd/conf.modules.d/00-mpm.conf and switch to the event or worker MPM.
Note that the HTTP/2 server-push feature does not work on the 64-bit ARM architecture, IBM Z, and IBM POWER, little endian.
httpd24 component, BZ#1327548
The mod_ssl module does not support the ALPN protocol on Red Hat Enterprise Linux 6, or on Red Hat Enterprise Linux 7.3 and earlier. Consequently, clients that support upgrading TLS connections to HTTP/2 only using ALPN are limited to HTTP/1.1 support.
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.
httpd24 component, BZ#1382706
When SELinux is enabled, the LD_LIBRARY_PATH environment variable is not passed through to CGI scripts invoked by httpd. As a consequence, in some cases it is impossible to invoke executables from Software Collections enabled in the /opt/rh/httpd24/service-environment file from CGI scripts run by httpd. To work around this problem, set LD_LIBRARY_PATH as desired from within the CGI script.
httpd24 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.
rh-python35, rh-python36 components, BZ#1499990
The pytz module, which is used by Babel for time zone support, is not included in the rh-python35, and rh-python36 Software Collections. Consequently, when the user tries to import the dates module from Babel, a traceback is returned. To work around this problem, install pytz through the pip package manager from the pypi public repository by using the pip install pytz command.
rh-python36 component
Certain complex trigonometric functions provided by numpy might return incorrect values on the 64-bit ARM architecture, IBM Z, and IBM POWER, little endian. The AMD64 and Intel 64 architectures are not affected by this problem.
python27 component, BZ#1330489
The python27-python-pymongo package has been updated to version 3.2.1. Note that this version is not fully compatible with the previously shipped version 2.5.2.
scl-utils component
In Red Hat Enterprise Linux 7.5 and earlier, due to an architecture-specific macro bug in the scl-utils package, the <collection>/root/usr/lib64/ directory does not have the correct package ownership on the 64-bit ARM architecture and on IBM POWER, little endian. As a consequence, this directory is not removed when a Software Collection is uninstalled. To work around this problem, manually delete <collection>/root/usr/lib64/ when removing a Software Collection.
ruby component
Determination of RubyGem installation paths is dependent on the order in which multiple Software Collections are enabled. The required order has been changed since Ruby 2.3.1 shipped in Red Hat Software Collections 2.3 to support dependent Collections. As a consequence, RubyGem paths, which are used for gem installation during an RPM build, are invalid when the Software Collections are supplied in an incorrect order. For example, the build fails if the RPM spec file contains scl enable rh-ror50 rh-nodejs6. To work around this problem, enable the rh-ror50 Software Collection last, for example, scl enable rh-nodejs6 rh-ror50.
maven component
When the user has installed both the Red Hat Enterprise Linux system version of maven-local package and the rh-maven*-maven-local package, XMvn, a tool used for building Java RPM packages, run from the Maven 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.
perl component
It is impossible to install more than one mod_perl.so library. As a consequence, it is not possible to use the mod_perl module from more than one Perl Software Collection.
postgresql component
The rh-postgresql9* 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, php, python, ruby, and ror components, BZ#1072319
When uninstalling the httpd24, rh-mariadb*, rh-mongodb*, rh-mysql*, rh-nodejs*, rh-perl*, rh-php*, python27, rh-python*, rh-ruby*, or rh-ror* 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 components, BZ#1194611
Since MariaDB 10 and MySQL 5.6, the rh-mariadb*-mariadb-server and rh-mysql*-mysql-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.
mariadb, mysql, postgresql, mongodb components
Red Hat Software Collections contains the MySQL 5.7, MySQL 8.0, MariaDB 10.2, MariaDB 10.3, PostgreSQL 9.6, PostgreSQL 10, PostgreSQL 12, MongoDB 3.4, and MongoDB 3.6 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/.

Other Notes

rh-ruby*, rh-python*, rh-php* components
Using Software Collections on a read-only NFS has several limitations.
  • Ruby gems cannot be installed while the rh-ruby* 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, an error message is displayed, for example: 
    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.
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-python35 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
python component
When the user tries to install more than one scldevel package from the python27 and rh-python* 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 rh-php* 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 rh-ruby* 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 rh-perl* 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 rh-nginx* 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).

1.6. Deprecated Functionality

httpd24 component, BZ#1434053
Previously, in an SSL/TLS configuration requiring name-based SSL virtual host selection, the mod_ssl module rejected requests with a 400 Bad Request error, if the host name provided in the Host: header did not match the host name provided in a Server Name Indication (SNI) header. Such requests are no longer rejected if the configured SSL/TLS security parameters are identical between the selected virtual hosts, in-line with the behavior of upstream mod_ssl.