mtpti5iD/redhat-docs_dataset huggingface dataset:
Chapter 35. Tuning Persistence Put the message journal on its own physical volume. One of the advantages of an append-only journal is that disk head movement is minimized. This advantage is lost if the disk is shared. When multiple processes, such as a transaction coordinator, databases, and other journals, read and write from the same disk, performance is impacted because the disk head must skip around between different files. If you are using paging or large messages, make sure they are also put on separate volumes. Tune the journal-min-files value. Set the journal-min-files parameter to the number of files that fits your average sustainable rate. If you frequently see new files being created on the journal data directory, meaning a lot data is being persisted, you need to increase the minimal number of files. This allows the journal to reuse, rather than create, new data files. Optimize the journal file size. The journal file size must be aligned to the capacity of a cylinder on the disk. The default value of 10MB should be enough on most systems. Use the AIO journal type. For Linux operating systems, keep your journal type as AIO . AIO scales better than Java NIO . Tune the journal-buffer-timeout value. Increasing the journal-buffer-timeout value results in increased throughput at the expense of latency. Tune the journal-max-io value. If you are using AIO , you might be able improve performance by increasing the journal-max-io parameter value. Do not change this value if you are using NIO .

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Chapter 1. Introduction to Red Hat Gluster Storage for Virtualization Red Hat Gluster Storage can be configured as a storage domain for Red Hat Virtualization, allowing you to store virtual machine images on Red Hat Gluster Storage instead of in network-attached storage appliances or a storage area network array. This guide shows you how to configure Red Hat Gluster Storage as a Red Hat Virtualization storage domain in a traditional, non-hyperconverged configuration. This configuration consists of Red Hat Virtualization hosts, and Red Hat Gluster Storage servers, as illustrated in Figure 1.1, "Architecture of integrated Red Hat Virtualization and Red Hat Gluster Storage" . Figure 1.1. Architecture of integrated Red Hat Virtualization and Red Hat Gluster Storage Important Red Hat Virtualization 3.3 onwards includes the GlusterFS storage domain to enable future support for the libgfapi protocol. The GlusterFS storage domain uses the same access mechanism as the POSIXFS domain.

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2.23. RHEA-2011:0623 - new package: perl-Class-MethodMaker A new perl-Class-MethodMaker package is now available for Red Hat Enterprise Linux 6. Class::MethodMaker is a Perl module that enables the creation of generic methods. This makes it easier to write accessor methods for objects that perform standard tasks. This enhancement update adds the perl-Class-MethodMaker package to Red Hat Enterprise Linux 6. (BZ# 669046 ) All users who require the Class::MethodMaker Perl module should install this new package.

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Chapter 6. Btrfs (Technology Preview) Note Btrfs is available as a Technology Preview feature in Red Hat Enterprise Linux 7 but has been deprecated since the Red Hat Enterprise Linux 7.4 release. It will be removed in a future major release of Red Hat Enterprise Linux. For more information, see Deprecated Functionality in the Red Hat Enterprise Linux 7.4 Release Notes. Btrfs is a generation Linux file system that offers advanced management, reliability, and scalability features. It is unique in offering snapshots, compression, and integrated device management. 6.1. Creating a btrfs File System In order to make a basic btrfs file system, use the following command: For more information on creating btrfs file systems with added devices and specifying multi-device profiles for metadata and data, refer to Section 6.4, "Integrated Volume Management of Multiple Devices" .

Commands:
mkfs.btrfs / dev / device
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Chapter 4. Certificate mapping rules for configuring authentication You might need to configure certificate mapping rules in the following scenarios: Certificates have been issued by the Certificate System of the Active Directory (AD) with which the IdM domain is in a trust relationship. Certificates have been issued by an external certificate authority. The IdM environment is large with many users using smart cards. In this case, adding full certificates can be complicated. The subject and issuer are predictable in most scenarios and therefore easier to add ahead of time than the full certificate. As a system administrator, you can create a certificate mapping rule and add certificate mapping data to a user entry even before a certificate is issued to a particular user. Once the certificate is issued, the user can log in using the certificate even though the full certificate has not yet been uploaded to the user entry. In addition, as certificates are renewed at regular intervals, certificate mapping rules reduce administrative overhead. When a user's certificate is renewed, the administrator does not have to update the user entry. For example, if the mapping is based on the Subject and Issuer values, and if the new certificate has the same subject and issuer as the old one, the mapping still applies. If, in contrast, the full certificate was used, then the administrator would have to upload the new certificate to the user entry to replace the old one. To set up certificate mapping: An administrator has to load the certificate mapping data or the full certificate into a user account. An administrator has to create a certificate mapping rule to allow successful logging into IdM for a user whose account contains a certificate mapping data entry that matches the information on the certificate. Once the certificate mapping rules have been created, when the end-user presents the certificate, stored either on a filesystem or a smart card , authentication is successful. Note The Key Distribution Center (KDC) has a cache for certificate mapping rules. The cache is populated on the first certauth request and it has a hard-coded timeout of 300 seconds. KDC will not see any changes to certificate mapping rules unless it is restarted or the cache expires. For details on the individual components that make up a mapping rule and how to obtain and use them, see Components of an identity mapping rule in IdM and Obtaining the issuer from a certificate for use in a matching rule . Note Your certificate mapping rules can depend on the use case for which you are using the certificate. For example, if you are using SSH with certificates, you must have the full certificate to extract the public key from the certificate.

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Chapter 2. December 2024 2.1. Support for tracking Red Hat OpenShift Virtualization With support for tracking Red Hat OpenShift Virtualization, you can now view costs that are directly associated with virtual machines (VMs) running on your OpenShift clusters. There is also a new API endpoint: /api/cost-management/v1/reports/openshift/resources/virtual-machines/ . To find your Red Hat OpenShift Virtualization data, click the Virtualization tab on the OpenShift details page. To learn about Red Hat OpenShift Virtualization, see Virtualization .

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function::user_string_quoted Name function::user_string_quoted - Retrieves and quotes string from user space Synopsis Arguments addr the user space address to retrieve the string from Description Returns the null terminated C string from a given user space memory address where any ASCII characters that are not printable are replaced by the corresponding escape sequence in the returned string. Note that the string will be surrounded by double quotes. On the rare cases when userspace data is not accessible at the given address, the address itself is returned as a string, without double quotes.

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user_string_quoted:string(addr:long)
4.3. Interrupts and IRQ Tuning An interrupt request (IRQ) is a request for service, sent at the hardware level. Interrupts can be sent by either a dedicated hardware line, or across a hardware bus as an information packet (a Message Signaled Interrupt, or MSI). When interrupts are enabled, receipt of an IRQ prompts a switch to interrupt context. Kernel interrupt dispatch code retrieves the IRQ number and its associated list of registered Interrupt Service Routines (ISRs), and calls each ISR in turn. The ISR acknowledges the interrupt and ignores redundant interrupts from the same IRQ, then queues a deferred handler to finish processing the interrupt and stop the ISR from ignoring future interrupts. The /proc/interrupts file lists the number of interrupts per CPU per I/O device. It displays the IRQ number, the number of that interrupt handled by each CPU core, the interrupt type, and a comma-delimited list of drivers that are registered to receive that interrupt. (Refer to the proc(5) man page for further details: man 5 proc ) IRQs have an associated "affinity" property, smp_affinity , which defines the CPU cores that are allowed to execute the ISR for that IRQ. This property can be used to improve application performance by assigning both interrupt affinity and the application's thread affinity to one or more specific CPU cores. This allows cache line sharing between the specified interrupt and application threads. The interrupt affinity value for a particular IRQ number is stored in the associated /proc/irq/ IRQ_NUMBER /smp_affinity file, which can be viewed and modified by the root user. The value stored in this file is a hexadecimal bit-mask representing all CPU cores in the system. As an example, to set the interrupt affinity for the Ethernet driver on a server with four CPU cores, first determine the IRQ number associated with the Ethernet driver: Use the IRQ number to locate the appropriate smp_affinity file: The default value for smp_affinity is f , meaning that the IRQ can be serviced on any of the CPUs in the system. Setting this value to 1 , as follows, means that only CPU 0 can service this interrupt: Commas can be used to delimit smp_affinity values for discrete 32-bit groups. This is required on systems with more than 32 cores. For example, the following example shows that IRQ 40 is serviced on all cores of a 64-core system: To service IRQ 40 on only the upper 32-cores of a 64-core system, you would do the following: Note On systems that support interrupt steering , modifying the smp_affinity of an IRQ sets up the hardware so that the decision to service an interrupt with a particular CPU is made at the hardware level, with no intervention from the kernel.

Commands:
grep eth0 /proc/interrupts 32: 0 140 45 850264 PCI-MSI-edge eth0
cat /proc/irq/32/smp_affinity f
echo 1 >/proc/irq/32/smp_affinity cat /proc/irq/32/smp_affinity 1
cat /proc/irq/40/smp_affinity ffffffff,ffffffff
echo 0xffffffff,00000000 > /proc/irq/40/smp_affinity cat /proc/irq/40/smp_affinity ffffffff,00000000
probe::nfs.proc.write_setup Name probe::nfs.proc.write_setup - NFS client setting up a write RPC task Synopsis nfs.proc.write_setup Values size bytes written in this execution prot transfer protocol version NFS version count bytes written in this execution bitmask0 V4 bitmask representing the set of attributes supported on this filesystem bitmask1 V4 bitmask representing the set of attributes supported on this filesystem offset the file offset how used to set args.stable. The stable value could be: NFS_UNSTABLE,NFS_DATA_SYNC,NFS_FILE_SYNC (in nfs.proc3.write_setup and nfs.proc4.write_setup) server_ip IP address of server Description The write_setup function is used to setup a write RPC task. It is not doing the actual write operation.

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Chapter 4. Working with SELinux The following sections give a brief overview of the main SELinux packages in Red Hat Enterprise Linux; installing and updating packages; which log files are used; the main SELinux configuration file; enabling and disabling SELinux; SELinux modes; configuring Booleans; temporarily and persistently changing file and directory labels; overriding file system labels with the mount command; mounting NFS volumes; and how to preserve SELinux contexts when copying and archiving files and directories. 4.1. SELinux Packages In Red Hat Enterprise Linux full installation, the SELinux packages are installed by default unless they are manually excluded during installation. If performing a minimal installation in text mode, the policycoreutils-python and the policycoreutils-gui package are not installed by default. Also, by default, SELinux runs in enforcing mode and the SELinux targeted policy is used. The following SELinux packages are installed on your system by default: policycoreutils provides utilities such as restorecon , secon , setfiles , semodule , load_policy , and setsebool , for operating and managing SELinux. selinux-policy provides a basic directory structure, the selinux-policy.conf file, and RPM macros. selinux-policy-targeted provides the SELinux targeted policy. libselinux - provides an API for SELinux applications. libselinux-utils provides the avcstat , getenforce , getsebool , matchpathcon , selinuxconlist , selinuxdefcon , selinuxenabled , and setenforce utilities. libselinux-python provides Python bindings for developing SELinux applications. The following packages are not installed by default but can be optionally installed by running the yum install <package-name> command: selinux-policy-devel provides utilities for creating a custom SELinux policy and policy modules. selinux-policy-doc provides manual pages that describe how to configure SELinux altogether with various services. selinux-policy-mls provides the MLS (Multi-Level Security) SELinux policy. setroubleshoot-server translates denial messages, produced when access is denied by SELinux, into detailed descriptions that can be viewed with the sealert utility, also provided in this package. setools-console provides the Tresys Technology SETools distribution, a number of utilities and libraries for analyzing and querying policy, audit log monitoring and reporting, and file context management. The setools package is a meta-package for SETools. The setools-gui package provides the apol and seaudit utilities. The setools-console package provides the sechecker , sediff , seinfo , sesearch , and findcon command-line utilities. Note that setools and setools-gui packages are available only when the Red Hat Network Optional channel is enabled. For further information, see Scope of Coverage Details . mcstrans translates levels, such as s0-s0:c0.c1023 , to a form that is easier to read, such as SystemLow-SystemHigh . policycoreutils-python provides utilities such as semanage , audit2allow , audit2why , and chcat , for operating and managing SELinux. policycoreutils-gui provides system-config-selinux , a graphical utility for managing SELinux.

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7.178. redhat-rpm-config 7.178.1. RHBA-2015:1396 - redhat-rpm-config bug fix update An updated redhat-rpm-config package that fixes several bugs is now available for Red Hat Enterprise Linux 6. The redhat-rpm-config package is used during the build of RPM packages to apply various default distribution options determined by Red Hat. Also, redhat-rpm-config provides a few Red Hat RPM macro customizations, such as those used during the building of Driver Update packages. Bug Fixes BZ# 842761 Prior to this update, the find-requires.ksyms script provided by the redhat-rpm-config package could not locate the kernel Application Binary Interface (ABI) reference files provided by the kabi-whitelists package. As a consequence, building an RPM that contained a kernel module (*.ko) resulted in the "KERNEL ABI COMPATIBILITY WARNING" error message, and no compatibility check was performed. With this update, the kernel ABI reference files can be successfully located, and ABI compatibility of kernel object files can now be verified in the described situation. BZ# 1179521 RPM scans files during the build process for dependencies, and if a file is accidentally detected as a script by libmagic, RPM parses the first line for the "#!" string to get the interpreter. Previously, RPM could pick up random data if the "#!" string was not included at the beginning of the file. With this update, the RPM verification process is more thorough, and incorrect requirements are no longer picked up. BZ# 1199983 With this update, the redhat-rpm-config package has been added as a dependency of the rpm-build package. A new RPM virtual provide has been added to the system-rpm-config package, which allows system-rpm-config to be required by rpm-build while still being able to be replaced by a third party package. Users of redhat-rpm-config are advised to upgrade to this updated package, which fixes these bugs.

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Chapter 4. Cluster Creation and Administration This chapter describes how to perform basic cluster administration with Pacemaker, including creating the cluster, managing the cluster components, and displaying cluster status. 4.1. Cluster Creation To create a running cluster, perform the following steps: Start the pcsd on each node in the cluster. Authenticate the nodes that will constitute the cluster. Configure and sync the cluster nodes. Start cluster services on the cluster nodes. The following sections described the commands that you use to perform these steps. 4.1.1. Starting the pcsd daemon The following commands start the pcsd service and enable pcsd at system start. These commands should be run on each node in the cluster. 4.1.2. Authenticating the Cluster Nodes The following command authenticates pcs to the pcs daemon on the nodes in the cluster. The user name for the pcs administrator must be hacluster on every node. It is recommended that the password for user hacluster be the same on each node. If you do not specify username or password , the system will prompt you for those parameters for each node when you execute the command. If you do not specify any nodes, this command will authenticate pcs on the nodes that are specified with a pcs cluster setup command, if you have previously executed that command. For example, the following command authenticates user hacluster on z1.example.com for both of the nodes in the cluster that consist of z1.example.com and z2.example.com . This command prompts for the password for user hacluster on the cluster nodes. Authorization tokens are stored in the file ~/.pcs/tokens (or /var/lib/pcsd/tokens ). 4.1.3. Configuring and Starting the Cluster Nodes The following command configures the cluster configuration file and syncs the configuration to the specified nodes. If you specify the --start option, the command will also start the cluster services on the specified nodes. If necessary, you can also start the cluster services with a separate pcs cluster start command. When you create a cluster with the pcs cluster setup --start command or when you start cluster services with the pcs cluster start command, there may be a slight delay before the cluster is up and running. Before performing any subsequent actions on the cluster and its configuration, it is recommended that you use the pcs cluster status command to be sure that the cluster is up and running. If you specify the --local option, the command will perform changes on the local node only. The following command starts cluster services on the specified node or nodes. If you specify the --all option, the command starts cluster services on all nodes. If you do not specify any nodes, cluster services are started on the local node only.

Commands:
systemctl start pcsd.service systemctl enable pcsd.service
pcs cluster auth [ node ] [...] [-u username ] [-p password ]
root@z1 ~]# pcs cluster auth z1.example.com z2.example.com Username: hacluster Password: z1.example.com: Authorized z2.example.com: Authorized
pcs cluster setup [--start] [--local] --name cluster_ name node1 [ node2 ] [...]
pcs cluster start [--all] [ node ] [...]
1.3. Running Additional Programs at Boot Time The /etc/rc.d/rc.local script is executed by the init command at boot time or when changing runlevels. Adding commands to the bottom of this script is an easy way to perform necessary tasks like starting special services or initialize devices without writing complex initialization scripts in the /etc/rc.d/init.d/ directory and creating symbolic links. The /etc/rc.serial script is used if serial ports must be setup at boot time. This script runs setserial commands to configure the system's serial ports. Refer to the setserial man page for more information.

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Appendix A. Using your subscription Streams for Apache Kafka is provided through a software subscription. To manage your subscriptions, access your account at the Red Hat Customer Portal. Accessing Your Account Go to access.redhat.com . If you do not already have an account, create one. Log in to your account. Activating a Subscription Go to access.redhat.com . Navigate to My Subscriptions . Navigate to Activate a subscription and enter your 16-digit activation number. Downloading Zip and Tar Files To access zip or tar files, use the customer portal to find the relevant files for download. If you are using RPM packages, this step is not required. Open a browser and log in to the Red Hat Customer Portal Product Downloads page at access.redhat.com/downloads . Locate the Streams for Apache Kafka for Apache Kafka entries in the INTEGRATION AND AUTOMATION category. Select the desired Streams for Apache Kafka product. The Software Downloads page opens. Click the Download link for your component. Installing packages with DNF To install a package and all the package dependencies, use: dnf install <package_name> To install a previously-downloaded package from a local directory, use: dnf install <path_to_download_package> Revised on 2024-10-22 10:43:11 UTC

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dnf install <package_name>
dnf install <path_to_download_package>