Chapter 14. Dynamic programming languages, web servers, database servers

This chapter lists the most notable changes to dynamic programming languages, web servers, and database servers between RHEL 8 and RHEL 9.

14.1. Notable changes to dynamic programming languages, web and database servers

Initial Application Streams versions in RHEL 9

RHEL 9 improves the Application Streams experience by providing initial Application Stream versions that can be installed as RPM packages using the traditional yum install command.

RHEL 9.0 Beta provides the following dynamic programming languages:

  • Node.js 16
  • Perl 5.32
  • PHP 8.0
  • Python 3.9
  • Ruby 3.0

RHEL 9.0 Beta includes the following version control systems:

  • Git 2.31
  • Subversion 1.14

The following web servers are distributed with RHEL 9.0 Beta:

  • Apache HTTP Server 2.4
  • nginx 1.20

The following proxy caching servers are available:

  • Varnish Cache 6.5
  • Squid 5.14

RHEL 9.0 Beta offers the following database servers:

  • MariaDB 10.5
  • MySQL 8.0
  • PostgreSQL 13
  • Redis 6.2

Some additional Application Stream versions will be distributed as modules with a shorter life cycle in future minor RHEL 9 releases.

Major differences in the Python ecosystem since RHEL 8

This section summarizes major changes in the Python ecosystem in RHEL 9 compared to RHEL 8.

The unversioned python command

The unversioned form of the python command (/usr/bin/python) is available in the python-unversioned-command package. On some systems, this package is not installed by default. To install the unversioned form of the python command manually, use the yum install /usr/bin/python command.

In RHEL 9, the unversioned form of the python command points to the default Python 3.9 version and it is an equivalent to the python3 and python3.9 commands.

The python command is intended for interactive sessions. In production, Red Hat recommends using python3 or python3.9 explicitly.

You can uninstall the unversioned python command by using the yum remove /usr/bin/python command. If you need a different python command, you can create custom symlinks in /usr/local/bin or ~/.local/bin or a Python virtual environment.

Several other unversioned commands are available, such as /usr/bin/pip in the python3-pip package. In RHEL 9, all unversioned commands point to the default Python 3.9 version.

Architecture-specific Python wheels

Architecture-specific Python wheels built on RHEL 9 newly adhere to the upstream architecture naming, which allows customers to build their Python wheels on RHEL 9 and install them on non-RHEL systems. Python wheels built on previous releases of RHEL are forward compatible and can be installed on RHEL 9. Note that this affects only wheels containing Python extensions, which are built for each architecture, not Python wheels with pure Python code, which is not architecture-specific.

Notable changes to libdb

RHEL 8 and RHEL 9 currently provide Berkeley DB (libdb) version 5.3.28, which is distributed under the LGPLv2 license. The upstream Berkeley DB version 6 is available under the AGPLv3 license, which is more restrictive.

The libdb package is deprecated as of RHEL 9 and might not be available in future major RHEL releases. Cryptographic algorithms have been removed from libdb in RHEL 9. Multiple libdb dependencies have been removed from RHEL 9.

Users of libdb are advised to migrate to a different key-value database. For more information, see the Knowledgebase article Available replacements for the deprecated Berkeley DB (libdb) in RHEL.