mtpti5iD/redhat-docs_dataset huggingface dataset:
4.5. Soft-Fencing Hosts Hosts can sometimes become non-responsive due to an unexpected problem, and though VDSM is unable to respond to requests, the virtual machines that depend upon VDSM remain alive and accessible. In these situations, restarting VDSM returns VDSM to a responsive state and resolves this issue. "SSH Soft Fencing" is a process where the Manager attempts to restart VDSM via SSH on non-responsive hosts. If the Manager fails to restart VDSM via SSH, the responsibility for fencing falls to the external fencing agent if an external fencing agent has been configured. Soft-fencing over SSH works as follows. Fencing must be configured and enabled on the host, and a valid proxy host (a second host, in an UP state, in the data center) must exist. When the connection between the Manager and the host times out, the following happens: On the first network failure, the status of the host changes to "connecting". The Manager then makes three attempts to ask VDSM for its status, or it waits for an interval determined by the load on the host. The formula for determining the length of the interval is configured by the configuration values TimeoutToResetVdsInSeconds (the default is 60 seconds) + [DelayResetPerVmInSeconds (the default is 0.5 seconds)]*(the count of running virtual machines on host) + [DelayResetForSpmInSeconds (the default is 20 seconds)] * 1 (if host runs as SPM) or 0 (if the host does not run as SPM). To give VDSM the maximum amount of time to respond, the Manager chooses the longer of the two options mentioned above (three attempts to retrieve the status of VDSM or the interval determined by the above formula). If the host does not respond when that interval has elapsed, vdsm restart is executed via SSH. If vdsm restart does not succeed in re-establishing the connection between the host and the Manager, the status of the host changes to Non Responsive and, if power management is configured, fencing is handed off to the external fencing agent. Note Soft-fencing over SSH can be executed on hosts that have no power management configured. This is distinct from "fencing": fencing can be executed only on hosts that have power management configured.

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10.2.4.6. The mod_perl Module The configuration for mod_perl has been moved from httpd.conf into the file /etc/httpd/conf.d/perl.conf . For this file to be loaded, and hence for mod_perl to work, the statement Include conf.d/*.conf must be included in httpd.conf as described in Section 10.2.1.3, "Dynamic Shared Object (DSO) Support" . Occurrences of Apache:: in httpd.conf must be replaced with ModPerl:: . Additionally, the manner in which handlers are registered has been changed. This is a sample Apache HTTP Server 1.3 mod_perl configuration: This is the equivalent mod_perl for Apache HTTP Server 2.0: Most modules for mod_perl 1.x should work without modification with mod_perl 2.x. XS modules require recompilation and may require minor Makefile modifications.

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<Directory /var/www/perl> SetHandler perl-script PerlHandler Apache::Registry Options +ExecCGI </Directory>
<Directory /var/www/perl> SetHandler perl-script PerlResponseHandler ModPerl::Registry Options +ExecCGI </Directory>
A.5. Troubleshooting with Serial Consoles Linux kernels can output information to serial ports. This is useful for debugging kernel panics and hardware issues with video devices or headless servers. To enable serial console output for KVM guests: Ensure that the domain XML file of the guest includes configuration for the serial console. For example: <console type='pty'> <source path='/dev/pts/16'/> <target type='virtio' port='1'/> <alias name='console1'/> </console> On the guest, follow the How can I enable serial console for Red Hat Enterprise Linux 7? article on Red Hat Knowledgebase. On the host, you can then access the serial console with the following command, where guestname is the name of the guest virtual machine: You can also use virt-manager to display the virtual text console. In the guest console window, select Serial 1 in Text Consoles from the View menu.

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<console type='pty'> <source path='/dev/pts/16'/> <target type='virtio' port='1'/> <alias name='console1'/> </console>
virsh console guestname
B.30. initscripts B.30.1. RHBA-2010:1004 - initscripts bug fix update An updated initscripts package that fixes a bug is now available for Red Hat Enterprise Linux 6. The initscripts package contains system scripts to boot your system, change runlevels, activate and deactivate most network interfaces, and shut the system down cleanly. Bug Fix BZ# 660327 Prior to this update, users were unable to set the VLAN tag to 0 when creating a logical network. With this update, the ifup script has been updated to permit this value, and the VLAN identification number can now be set to 0 as expected. All users are advised to upgrade to this updated package, which fixes this bug.

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Chapter 15. tags Optional. An operator-defined list of tags placed on each log by the collector or normalizer. The payload can be a string with whitespace-delimited string tokens or a JSON list of string tokens. Data type text file The path to the log file from which the collector reads this log entry. Normally, this is a path in the /var/log file system of a cluster node. Data type text offset The offset value. Can represent bytes to the start of the log line in the file (zero- or one-based), or log line numbers (zero- or one-based), so long as the values are strictly monotonically increasing in the context of a single log file. The values are allowed to wrap, representing a new version of the log file (rotation). Data type long

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B.2. Red Hat Access GUI Another highly recommended source of information is a desktop application Red Hat Access GUI , which lets you find help, answers, and utilize diagnostic services using Red Hat Knowledgebase, resources, and functionality. If you have an active account on the Red Hat Customer Portal , you can access additional information and tips of the Knowledgebase easily browsable by keywords. Red Hat Access GUI is already installed if you select to have the GNOME Desktop installed. For more information on the benefits, installation, and usage of this tool, see Red Hat Access GUI .

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Chapter 15. Volume cloning A clone is a duplicate of an existing storage volume that is used as any standard volume. You create a clone of a volume to make a point in time copy of the data. A persistent volume claim (PVC) cannot be cloned with a different size. You can create up to 512 clones per PVC for both CephFS and RADOS Block Device (RBD). 15.1. Creating a clone Prerequisites Source PVC must be in Bound state and must not be in use. Note Do not create a clone of a PVC if a Pod is using it. Doing so might cause data corruption because the PVC is not quiesced (paused). Procedure Click Storage Persistent Volume Claims from the OpenShift Web Console. To create a clone, do one of the following: Beside the desired PVC, click Action menu (...) Clone PVC . Click on the PVC that you want to clone and click Actions Clone PVC . Enter a Name for the clone. Select the access mode of your choice. Important The ReadOnlyMany (ROX) access mode is a Developer Preview feature and is subject to Developer Preview support limitations. Developer Preview releases are not intended to be run in production environments and are not supported through the Red Hat Customer Portal case management system. If you need assistance with ReadOnlyMany feature, reach out to the ocs-devpreview@redhat.com mailing list and a member of the Red Hat Development Team will assist you as quickly as possible based on availability and work schedules. See Creating a clone or restoring a snapshot with the new readonly access mode to use the ROX access mode. Enter the required size of the clone. Select the storage class in which you want to create the clone. The storage class can be any RBD storage class and it need not necessarily be the same as the parent PVC. Click Clone . You are redirected to the new PVC details page. Wait for the cloned PVC status to become Bound . The cloned PVC is now available to be consumed by the pods. This cloned PVC is independent of its dataSource PVC.

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19.2. Kernel Configuration Changes Hardware Enablement Bluetooth (disabled) WIRELESS (disabled) CPU_IDLE (enabled) GPIO_DWAPB (enabled) I2C (enabled) - Designware, QUP, and XLP9XX sensor support: IIO drivers (disabled) Accel sensors (disabled) light + orientation + interrupt trigger (disabled) Input driver mouse, synaptics, rmi4 LED Intel SS4200 (disabled) Generic IRQ CHIP (enabled) Hibernate (enabled) Clock Source DATA (enabled) OSS_CORE (disabled) all SND drivers (disabled) Networking Driver Support Thunder2 driver (enabled) Amazon (enabled) Altera (disabled) ARC (disabled) Broadcom B44, BCMGENET, BNX2X_VLAN, CNIC (disabled) Hisilicon (enabled) cadence MACB (disabled) Chelsio T3 (disabled) Intel E1000 (disabled) Mellanox (enabled) myri10GE (disabled) Qlogic - qla2xxx, netxen_nic, Qed, Qede (enabled) Qualcomm - qcom_emac (enabled) Broadcom - bcm7xxx (disabled) Infiniband Support CXBG4 (enabled) I40IW (enabled) MLX4 (enabled) MLX5 (enabled) IPOIB (enabled) IPOIB_CM (enabled) IPOIB_DEBUG (enabled) ISERT (enabled) SRP (enabled) SRPT (enabled) Core Kernel Support Schedule Imbalance (enabled) 48 bit VA support (enabled) tick cpu accounting (disabled) Context Tracking (enabled) RCU NOCB (enabled) CGROUP-Hugetlb (enabled) CRIU (enabled) BPF_SYSCALL (disabled) PERF_USE_VMALLOC (disabled) HZ_100/HZ (enabled) NO_HZ_IDLE (disabled) NO_HZ_FULL (enabled) BPF_EVENTS (disabled) LZ4 compression (disabled) BTREE (enabled) CPUMASK_OFFSTACK (disabled) DEBUG_INFO_DWARF4 (enabled) SCHEDSTATS (enabled) Striaght DEVMEM (disabled) Transparent Hugepage (HTP) (enabled) ZSMaLLOC_STAT, IDLE_PAGE_TRACKING(enabled) PAGE_EXTENSION and PAGE_POISONING (disabled) Networking Stack Support SLIP - (enabled) JME (disabled) IPVLAN (disabled) BPF_JIT (disabled) dccp (disabled) [ipv4] NET_FOU, Diag, CDG, NV (disabled) [ipv6] ILA (disabled), GRE (enabled) MAC80211 (disabled) netfilter_conntrack (enabled) Graphic and GPU Support DRM_I2C_SIL64 (disabled) TTY serial_nonstandard, cyclades, synclinkmp, synclink_gt, N_HDLC, serial_8250_MID (enabled) fbdev (enabled) USB - PHY (disabled) Storage Support Block scsi request (enabled) Block debugfs (enabled) Block Multi-Queue PCI (enabled) Block Multi-Queue VirtIO (enabled) Block Multi-Queue IOSched_deadline (enabled) MD Long Write -(disabled) SCSI - ARCMSR, AM53C974, WD719x, BNX2X_FCOE, BNX2_ISCSI, ESAS2R (disabled) SCSI - HISI_SAS (enabled) SPI - QUP, SLP (enabled) SSB (disabled) File Systems FS_DAX (enabled) BTRFS (disabled) Ceph (enabled) DLM (disabled) FSCAHE (disabled) GFS2 (disabled) Swap over NFS (disabled) NFS-FSCACHE (enabled) Virtualization and KVM Support KVM_IRQCHIP, KVM_IRQ_ROUTING, KVM_MSI (enabled) Virtio - noiommu (enabled)

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Chapter 4. Known issues Red Hat build of OpenJDK 17 might include known issues. Solutions might exist for some of these known issues. Debug packages moved to the RHEL 8.5 CodeReady Linux Builder (CRB) repository Description RHEL 8.5 moved the java-17-openjdk-slowdebug-debuginfo and java-17-openjdk-fastdebug-debuginfo packages to the CodeReady Linux Builder (CRB) repository, where the java-openjdk-slowdebug and java-openjdk-fastdebug packages are already located. This repository contains developer packages. Red Hat had planned to move these packages to the CRB repository earlier in the lifecycle of RHEL 8.5. However, this movement did not occur. You might have installed the java-17-openjdk-slowdebug-debuginfo and java-17-openjdk-fastdebug-debuginfo packages when these packages were located in the AppStream repository. You can check if you installed the java-17-openjdk-slowdebug-debuginfo or java-17-openjdk-fastdebug-debuginfo packages by issuing the following command in your CLI: USD rpm -qa | grep java-.*debug-debuginfo You can continue to use the java-17-openjdk-slowdebug-debuginfo and java-17-openjdk-fastdebug-debuginfo packages for debugging purposes on your Java application, but you must enable the CRB repository to receive updates for these packages. Workaround If you installed the java-17-openjdk-slowdebug-debuginfo and java-17-openjdk-fastdebug-debuginfo packages, you must choose one of the following options: Uninstall these packages by issuing the following command in your CLI: Enable the CRB repository by issuing the following command in your CLI: Important Red Hat does not fully support packages that are contained within the CRB repository. Ensure you understand the potential risks of using any unsupported debug packages on your Java applications. For more information about the CRB repository on RHEL 8.5, see Package Manifest guide in the Red Hat Enterprise Linux documentation.

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rpm -qa | grep java-.*debug-debuginfo
dnf remove java-17-openjdk-<package-name>
dnf config-manager --set-enabled rhel-8-crb-debug-rpms
3.6. Red Hat OpenStack Platform 16 Developer Tools for RHEL 8 x86_64 (RPMs) The following table outlines the packages included in the openstack-16-devtools-for-rhel-8-x86_64-rpms repository. Table 3.6. Red Hat OpenStack Platform 16 Developer Tools for RHEL 8 x86_64 (RPMs) Packages Name Version Advisory openstack-packstack 15.0.0-0.20200110015912.3be5458.el8ost RHEA-2020:0283 openstack-packstack-puppet 15.0.0-0.20200110015912.3be5458.el8ost RHEA-2020:0283 puppet-tempest 15.4.1-0.20191014141828.f74827b.el8ost RHEA-2020:0283 python3-junitxml 0.7-17.el8ost RHEA-2020:0283 subunit-filters 1.3.0-7.el8ost RHEA-2020:0283

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8.189. python-kerberos 8.189.1. RHBA-2014:1600 - python-kerberos bug fix update Updated python-kerberos packages that fix two bugs are now available for Red Hat Enterprise Linux 6. The python-kerberos packages contain a high-level wrapper for Kerberos Generic Security Service Application Program Interface (GSSAPI) operations. Bug Fixes BZ# 973379 Previously, the name of the egg-info file contained an incorrect version of the python-kerberos packages. As a consequence, the module dependency resolution did not work correctly. With this update, the egg-info file name contains the correct version, and resolving dependencies works as expected. BZ# 1057333 Prior to this update, the authenticate_gss_client_wrap() function miscalculated the length of the username string when wrapping it. Consequently, the Kerberos user name was not properly encoded into a GSSAPI message, and the authentication failed. This patch fixes the calculation of the username string length, and the authentication no longer fails. Users of python-kerberos are advised to upgrade to these updated packages, which fix these bugs.

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Chapter 18. Getting started with perf As a system administrator, you can use the perf tool to collect and analyze performance data of your system. 18.1. Introduction to perf The perf user-space tool interfaces with the kernel-based subsystem Performance Counters for Linux (PCL). perf is a powerful tool that uses the Performance Monitoring Unit (PMU) to measure, record, and monitor a variety of hardware and software events. perf also supports tracepoints, kprobes, and uprobes. 18.2. Installing perf This procedure installs the perf user-space tool. Procedure Install the perf tool: 18.3. Common perf commands perf stat This command provides overall statistics for common performance events, including instructions executed and clock cycles consumed. Options allow for selection of events other than the default measurement events. perf record This command records performance data into a file, perf.data , which can be later analyzed using the perf report command. perf report This command reads and displays the performance data from the perf.data file created by perf record . perf list This command lists the events available on a particular machine. These events will vary based on performance monitoring hardware and software configuration of the system. perf top This command performs a similar function to the top utility. It generates and displays a performance counter profile in realtime. perf trace This command performs a similar function to the strace tool. It monitors the system calls used by a specified thread or process and all signals received by that application. perf help This command displays a complete list of perf commands. Additional resources Add the --help option to a subcommand to open the man page.

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yum install perf
Chapter 25. PHP (DEPRECATED) Overview PHP is a widely-used general-purpose scripting language that is especially suited for Web development. The PHP support is part of the camel-script module. Important PHP in Apache Camel is deprecated and will be removed in a future release. Adding the script module To use PHP in your routes you need to add a dependency on camel-script to your project as shown in Example 25.1, "Adding the camel-script dependency" . Example 25.1. Adding the camel-script dependency Static import To use the php() static method in your application code, include the following import statement in your Java source files: Built-in attributes Table 25.1, "PHP attributes" lists the built-in attributes that are accessible when using PHP. Table 25.1. PHP attributes Attribute Type Value context org.apache.camel.CamelContext The Camel Context exchange org.apache.camel.Exchange The current Exchange request org.apache.camel.Message The IN message response org.apache.camel.Message The OUT message properties org.apache.camel.builder.script.PropertiesFunction Function with a resolve method to make it easier to use the properties component inside scripts. The attributes all set at ENGINE_SCOPE . Example Example 25.2, "Route using PHP" shows a route that uses PHP. Example 25.2. Route using PHP Using the properties component To access a property value from the properties component, invoke the resolve method on the built-in properties attribute, as follows: Where PropKey is the key of the property you want to resolve, where the key value is of String type. For more details about the properties component, see Properties in the Apache Camel Component Reference Guide .

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<!-- Maven POM File --> <dependencies> <dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-script</artifactId> <version>USD{camel-version}</version> </dependency> </dependencies>
import static org.apache.camel.builder.script.ScriptBuilder.*;
<camelContext> <route> <from uri="direct:start"/> <choice> <when> <language language="php">strpos(request.headers.get('user'), 'admin')!== FALSE</language> <to uri="seda:adminQueue"/> </when> <otherwise> <to uri="seda:regularQueue"/> </otherwise> </choice> </route> </camelContext>
.setHeader("myHeader").php("properties.resolve( PropKey )")
Chapter 5. Installation environment options for Red Hat Process Automation Manager With Red Hat Process Automation Manager, you can set up a development environment to develop business applications, a runtime environment to run those applications to support decisions, or both. Development environment : Typically consists of one Business Central installation and at least one KIE Server installation. You can use Business Central to design decisions and other artifacts, and you can use KIE Server to execute and test the artifacts that you created. Runtime environment : Consists of one or more KIE Server instances with or without Business Central. Business Central has an embedded Process Automation Manager controller. If you install Business Central, use the Menu Deploy Execution servers page to create and maintain containers. If you want to automate KIE Server management without Business Central, you can use the headless Process Automation Manager controller. You can also cluster both development and runtime environments. A clustered development or runtime environment consists of a unified group or cluster of two or more servers. The primary benefit of clustering Red Hat Process Automation Manager development environments is high availability and enhanced collaboration, while the primary benefit of clustering Red Hat Process Automation Manager runtime environments is high availability and load balancing. High availability decreases the chance of data loss when a single server fails. When a server fails, another server fills the gap by providing a copy of the data that was on the failed server. When the failed server comes online again, it resumes its place in the cluster. Note Clustering of the runtime environment is currently supported on Red Hat JBoss EAP 7.4 and Red Hat OpenShift Container Platform only.

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4.3. Deploy JBoss Data Grid in JBoss Enterprise Web Server Red Hat JBoss Data Grid supports JBoss Enterprise Web Server in Library and Remote Client Server mode. To use JBoss Data Grid with JBoss Enterprise Web Server, bundle the JDG libraries in a web application and deploy the application on the server. For further information on how to deploy JBoss Data Grid on JBoss Enterprise Web Server, see ( Section 14.4, "The (Non-transactional) CarMart Quickstart Using JBoss Enterprise Web Server" and Section 14.6, "The (Non-Transactional) CarMart Quickstart in Remote Client-Server Mode (JBoss Enterprise Web Server)" . Report a bug

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B.10.4. RHBA-2012:0374 - corosync bug fix update Updated corosync packages that fix one bug are now available for Red Hat Enterprise Linux 6 Extended Update Support. The corosync packages provide the Corosync Cluster Engine and C Application Programming Interfaces (APIs) for Red Hat Enterprise Linux cluster software. Bug Fix BZ# 791234 Previously, the range condition for the update_aru() function could cause incorrect check of message IDs. Due to this, in rare cases, the corosync utility entered the "FAILED TO RECEIVE" state, and so failed to receive multicast packets. With this update, the range value in the update_aru() function is no longer checked for; the fail_to_recv_const constant performs such checks. Now, corosync does not fail to receive packets. All users of corosync are advised to upgrade to these updated packages, which fix this bug.

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Chapter 8. Updating the Red Hat build of OpenTelemetry For version upgrades, the Red Hat build of OpenTelemetry Operator uses the Operator Lifecycle Manager (OLM), which controls installation, upgrade, and role-based access control (RBAC) of Operators in a cluster. The OLM runs in the OpenShift Container Platform by default. The OLM queries for available Operators as well as upgrades for installed Operators. When the Red Hat build of OpenTelemetry Operator is upgraded to the new version, it scans for running OpenTelemetry Collector instances that it manages and upgrades them to the version corresponding to the Operator's new version. 8.1. Additional resources Operator Lifecycle Manager concepts and resources Updating installed Operators

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