mtpti5iD/redhat-docs_dataset huggingface dataset:
Chapter 2. Configuring ModSecurity on RHEL When you install Red Hat JBoss Core Services on Red Hat Enterprise Linux (RHEL), you can configure the ModSecurity module to function as a web application firewall (WAF) for the Apache HTTP Server. Note JBCS 2.4.57 does not currently provide an archive file distribution of the Apache HTTP Server for RHEL 9. 2.1. ModSecurity dependencies on RHEL ModSecurity has several dependencies to function successfully. Some of these dependencies are already included as a part of Red Hat JBoss Core Services. The following table provides a list of ModSecurity dependencies: Dependency Part of JBCS on RHEL? Apache Portable Runtimes (APR) Yes APR-Util Yes mod_unique_id Yes libcurl Yes Perl-Compatible Regular Expressions (PCRE) Yes libxml2 No Note On RHEL, Red Hat JBoss Core Services includes all of these dependencies except the libxml2 library. 2.2. ModSecurity installation on RHEL The ModSecurity module is included as part of a Red Hat JBoss Core Services installation. You can follow the procedures in the Red Hat JBoss Core Services Apache HTTP Server Installation Guide to download and install the Apache HTTP Server for your operating system. Additional resources Red Hat JBoss Core Services Apache HTTP Server Installation Guide 2.3. Loading ModSecurity You can load the ModSecurity module by using the LoadModule command. Procedure To load the ModSecurity module, enter the following command: 2.4. Configuring the rules directory on RHEL ModSecurity functionality requires that you create rules that the system uses. Apache HTTP Server provides a preconfigured mod_security.conf.sample file in the HTTPD_HOME /modsecurity.d directory. To use ModSecurity rules, you must modify the mod_security.conf.sample file with settings that are appropriate for your environment. You can store the ModSecurity rules in the modsecurity.d directory or the modsecurity.d/activated_rules subdirectory. Procedure Go to the HTTPD_HOME /modsecurity.d directory. Rename the mod_security.conf.sample file to mod_security.conf : Open the mod_security.conf file and specify parameters for all the configuration directives that you want to use with the ModSecurity rules. 2.5. Key ModSecurity configuration options You can use key ModSecurity configuration options to improve the performance of regular expressions, investigate ModSecurity 2.6 phase one moving to phase two hook, and allow use of certain directives in .htaccess files. enable-pcre-jit Enables Just-In-Time (JIT) compiler support in the Perl-Compatible Regular Expressions (PCRE) library 8.20 or later to improve the performance of regular expressions. enable-request-early Enables testing of the ModSecurity 2.6 move from phase one to phase two hook enable-htaccess-config Enables use of directives in .htaccess files when AllowOverride Options is set

Commands:
LoadModule security2_module modules/mod_security2.so
mv mod_security.conf.sample ./mod_security.conf
5.364. xorg-x11-drv-mga 5.364.1. RHEA-2012:0940 - xorg-x11-drv-mga enhancement update Updated xorg-x11-drv-mga packages that add an enhancement are now available for Red Hat Enterprise Linux 6. The xorg-x11-drv-mga packages provide a video driver for Matrox G-series chipsets for the X.Org implementation of the X Window System. Enhancement BZ# 657580 RandR 1.2 support for G200-based graphics chipsets has been added. It allows dynamic reconfiguration of display settings to match the currently plugged in monitor. This is particularly important on servers, as they often start with no monitor attached, having it attached later in runtime. All users of xorg-x11-drv-mga are advised to upgrade to these updated packages, which add this enhancement.

Commands:
23.8. Time Zone Configuration Set your time zone by selecting the city closest to your computer's physical location. Click on the map to zoom in to a particular geographical region of the world. Specify a time zone even if you plan to use NTP (Network Time Protocol) to maintain the accuracy of the system clock. From here there are two ways for you to select your time zone: Using your mouse, click on the interactive map to select a specific city (represented by a yellow dot). A red X appears indicating your selection. You can also scroll through the list at the bottom of the screen to select your time zone. Using your mouse, click on a location to highlight your selection. Select System clock uses UTC . The system clock is a piece of hardware on your computer system. Red Hat Enterprise Linux uses the timezone setting to determine the offset between the local time and UTC on the system clock. This behavior is standard for systems that use UNIX, Linux, and similar operating systems. Click to proceed. Note To change your time zone configuration after you have completed the installation, use the Time and Date Properties Tool . Type the system-config-date command in a shell prompt to launch the Time and Date Properties Tool . If you are not root, it prompts you for the root password to continue.

Commands:
7.293. yum-rhn-plugin 7.293.1. RHBA-2013:0389 - yum-rhn-plugin bug fix update Updated yum-rhn-plugin packages that fix several bugs are now available for Red Hat Enterprise Linux 6. The yum-rhn-plugin packages make it possible to receive content from Red Hat Network in yum. Bug Fixes BZ#789092 Previously, yum-rhn-plugin ignored the timeout value set for yum. In some scenarios with slow networking, this could cause yum to timeout when communicating with Red Hat Network. Now, yum-rhnplugin abides by the timeout set for all yum repositories. BZ#802636 Previously, the check-update utility could in certain cases incorrectly return a 0 error code if an error occurred. With this update, "1" is returned if an error occurs. BZ#824193 Prior to this update, applying automatic updates with the yum-rhn-plugin utility on Red Hat Enterprise Linux 6 system could fail with an "empty transaction" error message. This was because the cached version of yum-rhn-plugin metadata was not up-to-date. With this update, yum-rhn-plugin downloads new metadata if available, ensuring that all packages are available for download. BZ# 830219 Previously, the messaging in yum-rhn-plugin was specific only to Red Hat Network Classic scenarios. This update clarifies what source yum-rhn-plugin is receiving updates from to reduce confusion. BZ# 831234 Prior to this update, yum-rhn-plugin did not correctly try the alternate server URLs provided if the first option failed. This update ensures that fail-over situations are handled correctly. All users of yum-rhn-plugin are advised to upgrade to these updated packages which fix these bugs.

Commands:
40.4. Saving Data Sometimes it is useful to save samples at a specific time. For example, when profiling an executable, it may be useful to gather different samples based on different input data sets. If the number of events to be monitored exceeds the number of counters available for the processor, multiple runs of OProfile can be used to collect data, saving the sample data to different files each time. To save the current set of sample files, execute the following command, replacing <name> with a unique descriptive name for the current session. The directory /var/lib/oprofile/samples/ name / is created and the current sample files are copied to it.

Commands:
opcontrol --save= <name>
3.5.2. Reading Values From Arrays You can also read values from an array the same way you would read the value of a variable. To do so, include the array_name [ index_expression ] statement as an element in a mathematical expression. For example: Example 3.13. Using Array Values in Simple Computations This example assumes that the array foo was built using the construct in Example 3.12, "Associating Timestamps to Process Names" (from Section 3.5.1, "Assigning an Associated Value" ). This sets a timestamp that will serve as a reference point , to be used in computing for delta . The construct in Example 3.13, "Using Array Values in Simple Computations" computes a value for the variable delta by subtracting the associated value of the key tid() from the current gettimeofday_s() . The construct does this by reading the value of tid() from the array. This particular construct is useful for determining the time between two events, such as the start and completion of a read operation. Note If the index_expression cannot find the unique key, it returns a value of 0 (for numerical operations, such as Example 3.13, "Using Array Values in Simple Computations" ) or a null/empty string value (for string operations) by default.

Commands:
delta = gettimeofday_s() - foo[tid()]
Chapter 2. Installation This chapter guides you through the steps to install AMQ Core Protocol JMS in your environment. 2.1. Prerequisites You must have a subscription to access AMQ release files and repositories. To build programs with AMQ Core Protocol JMS, you must install Apache Maven . To use AMQ Core Protocol JMS, you must install Java. 2.2. Using the Red Hat Maven repository Configure your Maven environment to download the client library from the Red Hat Maven repository. Procedure Add the Red Hat repository to your Maven settings or POM file. For example configuration files, see Section B.1, "Using the online repository" . <repository> <id>red-hat-ga</id> <url>https://maven.repository.redhat.com/ga</url> </repository> Add the library dependency to your POM file. <dependency> <groupId>org.apache.activemq</groupId> <artifactId>artemis-jms-client</artifactId> <version>2.16.0.redhat-00022</version> </dependency> The client is now available in your Maven project. 2.3. Installing a local Maven repository As an alternative to the online repository, AMQ Core Protocol JMS can be installed to your local filesystem as a file-based Maven repository. Procedure Use your subscription to download the AMQ Broker 7.8.2 Maven repository .zip file. Extract the file contents into a directory of your choosing. On Linux or UNIX, use the unzip command to extract the file contents. USD unzip amq-broker-7.8.2-maven-repository.zip On Windows, right-click the .zip file and select Extract All . Configure Maven to use the repository in the maven-repository directory inside the extracted install directory. For more information, see Section B.2, "Using a local repository" . 2.4. Installing the examples Procedure Use your subscription to download the AMQ Broker 7.8.2 .zip file. Extract the file contents into a directory of your choosing. On Linux or UNIX, use the unzip command to extract the file contents. USD unzip amq-broker-7.8.2.zip On Windows, right-click the .zip file and select Extract All . When you extract the contents of the .zip file, a directory named amq-broker-7.8.2 is created. This is the top-level directory of the installation and is referred to as <install-dir> throughout this document.

Commands:
<repository> <id>red-hat-ga</id> <url>https://maven.repository.redhat.com/ga</url> </repository>
<dependency> <groupId>org.apache.activemq</groupId> <artifactId>artemis-jms-client</artifactId> <version>2.16.0.redhat-00022</version> </dependency>
unzip amq-broker-7.8.2-maven-repository.zip
unzip amq-broker-7.8.2.zip
Chapter 5. Installing the Ansible Automation Platform Operator When installing the Ansible Automation Platform operator the preferred method of deployment is to install the cluster-scoped operator on a targeted namespace with manual update approval. The main advantage of this deployment method is it impacts only resources within the targeted namespace(s) that can in turn provide flexibility when wanting to limit the scope of the AAP operator in how it is handled over different namespaces. For instance, if you intend to have separate devel and prod namespaces to manage your different AAP deployments while testing upgrades. The steps to deploy the Ansible Automation Platform operator are as follows. Log in to the Red Hat OpenShift web console using your cluster credentials. In the left-hand navigation menu, select Operators OperatorHub. Search for Ansible Automation Platform and select it. On the Ansible Automation Platform Install page, select "Install". On the "Install Operator" page, select the appropriate update channel, stable-2.3-cluster-scoped select the appropriate installation mode, A specific namespace on the cluster select the appropriate installed namespace, Operator recommended Namespace: aap select the appropriate update approval, e.g. Manual . Click Install . Click Approve on the Manual approval required. The process to install the Ansible Automation Platform may take a few minutes prior to being available. Once the installation is complete, select the View Operator button to view the installed operator in the namespace specified during the installation (e.g. aap ). Note This AAP operator deployment only targets the namespace aap . If additional namespaces are to be targeted (managed) by the AAP operator, one must add them to the OperatorGroup spec file. Details Appendix F, Adding additional managed namespaces to the AAP Operator . Note The default resource values for the Ansible Automation Platform operator are suitable for typical installations. However, if deploying a large number of automation controller and automation hub environments, it is recommended to increase the resource threshold for the Ansible Automation Platform operator within the subscription spec using subscription.spec.config.resources . This ensures that the operator has sufficient resources to handle the increased workload and prevent performance issues.

Commands:
3.6. Linux bridge A Linux bridge is a software device that uses packet forwarding in a packet-switched network. Bridging allows multiple network interface devices to share the connectivity of one NIC and appear on a network as separate physical devices. The bridge examines a packet's source addresses to determine relevant target addresses. Once the target address is determined, the bridge adds the location to a table for future reference. This allows a host to redirect network traffic to virtual machine associated vNICs that are members of a bridge. Custom properties can be defined for both the bridge and the Ethernet connection. VDSM passes the network definition and custom properties to the setup network hook script.

Commands:
Chapter 17. Enabling kdump For your RHEL 8 systems, you can configure enabling or disabling the kdump functionality on a specific kernel or on all installed kernels. However, you must routinely test the kdump functionality and validate its working status. 17.1. Enabling kdump for all installed kernels The kdump service starts by enabling kdump.service after the kexec tool is installed. You can enable and start the kdump service for all kernels installed on the machine. Prerequisites You have administrator privileges. Procedure Add the crashkernel= command-line parameter to all installed kernels: xxM is the required memory in megabytes. Enable the kdump service: Verification Check that the kdump service is running: 17.2. Enabling kdump for a specific installed kernel You can enable the kdump service for a specific kernel on the machine. Prerequisites You have administrator privileges. Procedure List the kernels installed on the machine. Add a specific kdump kernel to the system's Grand Unified Bootloader (GRUB) configuration. For example: xxM is the required memory reserve in megabytes. Enable the kdump service. Verification Check that the kdump service is running. 17.3. Disabling the kdump service You can stop the kdump.service and disable the service from starting on your RHEL 8 systems. Prerequisites Fulfilled requirements for kdump configurations and targets. For details, see Supported kdump configurations and targets . All configurations for installing kdump are set up according to your needs. For details, see Installing kdump . Procedure To stop the kdump service in the current session: To disable the kdump service: Warning It is recommended to set kptr_restrict=1 as default. When kptr_restrict is set to (1) as default, the kdumpctl service loads the crash kernel regardless of whether the Kernel Address Space Layout ( KASLR ) is enabled. If kptr_restrict is not set to 1 and KASLR is enabled, the contents of /proc/kore file are generated as all zeros. The kdumpctl service fails to access the /proc/kcore file and load the crash kernel. The kexec-kdump-howto.txt file displays a warning message, which recommends you to set kptr_restrict=1 . Verify for the following in the sysctl.conf file to ensure that kdumpctl service loads the crash kernel: Kernel kptr_restrict=1 in the sysctl.conf file. Additional resources Managing systemd

Commands:
grubby --update-kernel=ALL --args="crashkernel=xxM"
systemctl enable --now kdump.service
systemctl status kdump.service ○ kdump.service - Crash recovery kernel arming Loaded: loaded (/usr/lib/systemd/system/kdump.service; enabled; vendor preset: disabled) Active: active (live)
ls -a /boot/vmlinuz- * /boot/vmlinuz-0-rescue-2930657cd0dc43c2b75db480e5e5b4a9 /boot/vmlinuz-4.18.0-330.el8.x86_64 /boot/vmlinuz-4.18.0-330.rt7.111.el8.x86_64
grubby --update-kernel= vmlinuz-4.18.0-330.el8.x86_64 --args="crashkernel= xxM "
systemctl enable --now kdump.service
systemctl status kdump.service ○ kdump.service - Crash recovery kernel arming Loaded: loaded (/usr/lib/systemd/system/kdump.service; enabled; vendor preset: disabled) Active: active (live)
systemctl stop kdump.service
systemctl disable kdump.service
Chapter 1. Supported conversion paths Important Red Hat recommends that you seek the support of Red Hat Consulting services to ensure that the conversion process is smooth. Currently, it is possible to convert your systems from the following Linux distributions and versions to the corresponding minor version of RHEL listed in Table 1.1. Table 1.1. Supported conversion paths Source OS Source version Target OS and version Product Variant Available Conversion Methods Alma Linux 9.5 RHEL 9.5 N/A Command line, Satellite 8.10 RHEL 8.10 N/A Command line, Satellite 8.8 RHEL 8.8 EUS N/A Command line, Satellite CentOS Linux 8.5 RHEL 8.5 N/A Command line, Satellite 7.9 RHEL 7.9 Server Command line, Satellite, Red Hat Insights Oracle Linux 9.5 RHEL 9.5 N/A Command line, Satellite 8.10 RHEL 8.10 N/A Command line, Satellite 7.9 RHEL 7.9 Server Command line, Satellite Rocky Linux 9.5 RHEL 9.5 N/A Command line, Satellite 8.10 RHEL 8.10 N/A Command line, Satellite 8.8 RHEL 8.8 EUS N/A Command line, Satellite Because the last available minor version of CentOS Linux is CentOS Linux 8.5, it is not possible to convert from CentOS Linux 8 directly to the latest available minor version of RHEL 8. It is recommended to update your system to the latest version of RHEL after the conversion. RHEL 7 reaches the end of the Maintenance Support Phase on June 30, 2024. If you are converting to RHEL 7 and plan to stay on RHEL 7, it is strongly recommended to purchase the Extended Life Cycle Support (ELS) add-on subscription. If you plan to convert to RHEL 7 and then immediately upgrade to RHEL 8 or later, an ELS subscription is not needed. Note that without ELS, you have limited support for RHEL 7, including for the upgrade from RHEL 7 to RHEL 8. For more information, see the Red Hat Enterprise Linux Life Cycle and the Convert2RHEL Support Policy . In addition to the above supported conversion paths, it is also possible to perform an unsupported conversion from Scientific Linux 7, CentOS Stream 8, and CentOS Stream 9 to RHEL. For information about unsupported conversions, see How to perform an unsupported conversion from a RHEL-derived Linux distribution to RHEL . For information about Red Hat's support policy for Linux distribution conversions, see Convert2RHEL Support Policy .

Commands:
3.2.3. Tuning CPUfreq Policy and Speed Once you have chosen an appropriate CPUfreq governor, you can view CPU speed and policy information with the cpupower frequency-info command and further tune the speed of each CPU with options for cpupower frequency-set . For cpupower frequency-info , the following options are available: --freq - Shows the current speed of the CPU according to the CPUfreq core, in KHz. --hwfreq - Shows the current speed of the CPU according to the hardware, in KHz (only available as root). --driver - Shows what CPUfreq driver is used to set the frequency on this CPU. --governors - Shows the CPUfreq governors available in this kernel. If you wish to use a CPUfreq governor that is not listed in this file, refer to Procedure 3.2, "Enabling a CPUfreq Governor" in Section 3.2.2, "CPUfreq Setup" for instructions on how to do so. --affected-cpus - Lists CPUs that require frequency coordination software. --policy - Shows the range of the current CPUfreq policy, in KHz, and the currently active governor. --hwlimits - Lists available frequencies for the CPU, in KHz. For cpupower frequency-set , the following options are available: --min <freq> and --max <freq> - Set the policy limits of the CPU, in KHz. Important When setting policy limits, you should set --max before --min . --freq <freq> - Set a specific clock speed for the CPU, in KHz. You can only set a speed within the policy limits of the CPU (as per --min and --max ). --governor <gov> - Set a new CPUfreq governor. Note If you do not have the cpupowerutils package installed, CPUfreq settings can be viewed in the tunables found in /sys/devices/system/cpu/ [cpuid] /cpufreq/ . Settings and values can be changed by writing to these tunables. For example, to set the minimum clock speed of cpu0 to 360 KHz, use:

Commands:
echo 360000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
4.164. lohit-tamil-fonts 4.164.1. RHEA-2011:1139 - lohit-tamil-fonts enhancement update An updated lohit-tamil-fonts package which adds one enhancement is now available for Red Hat Enterprise Linux 6. The lohit-tamil-fonts package provides a free Tamil TrueType/OpenType font. Enhancement BZ# 691295 Unicode 6.0, the most recent major version of the Unicode standard, introduces the Indian Rupee Sign (U+20B9), the new official Indian currency symbol. With this update, the lohit-tamil-fonts package now includes a glyph for this new character. All users requiring the Indian rupee sign should install this updated package, which adds this enhancement.

Commands:
Chapter 3. alt-java and java uses Depending on your needs, you can use either the alt-java binary or the java binary to run your application's code. 3.1. alt-java usage Use alt-java for any applications that run untrusted code. Be aware that using alt-java is not a solution to all speculative execution vulnerabilities. 3.2. java usage Use the java binary for performance-critical tasks in a secure environment. Most RPMs in a Red Hat Enterprise Linux system use the java binary, except for IcedTea-Web. IcedTea-Web uses alt-java as its launcher, so you can use IcedTea-Web to run untrusted code. Additional resources See Java and Speculative Execution Vulnerabilities .

Commands: