mtpti5iD/redhat-docs_dataset huggingface dataset:
8.4. Guest Virtual Machine Memory Allocation The following procedure shows how to allocate memory for a guest virtual machine. This allocation and assignment works only at boot time and any changes to any of the memory values will not take effect until the reboot. The maximum memory that can be allocated per guest is 4 TiB, providing that this memory allocation is not more than what the host physical machine resources can provide. Valid memory units include: b or bytes for bytes KB for kilobytes (10 3 or blocks of 1,000 bytes) k or KiB for kibibytes (2 10 or blocks of 1024 bytes) MB for megabytes (10 6 or blocks of 1,000,000 bytes) M or MiB for mebibytes (2 20 or blocks of 1,048,576 bytes) GB for gigabytes (10 9 or blocks of 1,000,000,000 bytes) G or GiB for gibibytes (2 30 or blocks of 1,073,741,824 bytes) TB for terabytes (10 12 or blocks of 1,000,000,000,000 bytes) T or TiB for tebibytes (2 40 or blocks of 1,099,511,627,776 bytes) Note that all values will be rounded up to the nearest kibibyte by libvirt, and may be further rounded to the granularity supported by the hypervisor. Some hypervisors also enforce a minimum, such as 4000KiB (or 4000 x 2 10 or 4,096,000 bytes). The units for this value are determined by the optional attribute memory unit , which defaults to the kibibytes (KiB) as a unit of measure where the value given is multiplied by 2 10 or blocks of 1024 bytes. In the cases where the guest virtual machine crashes the optional attribute dumpCore can be used to control whether the guest virtual machine's memory should be included in the generated coredump ( dumpCore='on' ) or not included ( dumpCore='off' ). Note that the default setting is on so if the parameter is not set to off , the guest virtual machine memory will be included in the coredump file. The currentMemory attribute determines the actual memory allocation for a guest virtual machine. This value can be less than the maximum allocation, to allow for ballooning up the guest virtual machines memory on the fly. If this is omitted, it defaults to the same value as the memory element. The unit attribute behaves the same as for memory. In all cases for this section, the domain XML needs to be altered as follows:

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<domain> <memory unit='KiB' dumpCore='off'>524288</memory> <!-- changes the memory unit to KiB and does not allow the guest virtual machine's memory to be included in the generated coredump file --> <currentMemory unit='KiB'>524288</currentMemory> <!-- makes the current memory unit 524288 KiB --> </domain>
14.3.2. Support for SSH Certificates Support for certificate authentication of users and hosts using the new OpenSSH certificate format was introduced in Red Hat Enterprise Linux 6.5, in the openssh-5.3p1-94.el6 package. If required, to ensure the latest OpenSSH package is installed, enter the following command as root :

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~]# yum install openssh Package openssh-5.3p1-104.el6_6.1.i686 already installed and latest version Nothing to do
21.6. 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. The subsections in this section cover setting up serial console output for host physical machines using the KVM hypervisor. This section covers how to enable serial console output for fully virtualized guests. Fully virtualized guest serial console output can be viewed with the virsh console command. Be aware fully virtualized guest serial consoles have some limitations. Present limitations include: output data may be dropped or scrambled. The serial port is called ttyS0 on Linux or COM1 on Windows. You must configure the virtualized operating system to output information to the virtual serial port. To output kernel information from a fully virtualized Linux guest into the domain, modify the /boot/grub/grub.conf file. Append the following to the kernel line: console=tty0 console=ttyS0,115200 . Reboot the guest. On the host, access the serial console with the following command: 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.

Commands:
title Red Hat Enterprise Linux Server (2.6.32-36.x86-64) root (hd0,0) kernel /vmlinuz-2.6.32-36.x86-64 ro root=/dev/volgroup00/logvol00 console=tty0 console=ttyS0,115200 initrd /initrd-2.6.32-36.x86-64.img
virsh console
4.4. Model Validation Models must be in a valid state in order to be used for data access. Validation of a single model means that it must be in a self-consistent and complete state, meaning that there are no missing pieces and no references to non-existent entities. Validation of multiple models checks that all inter-model dependencies are present and resolvable. Models must always be validated when they are deployed in a VDB for data access purposes. Teiid Designer will automatically validate all models whenever they are saved. Note The Project > Build Automatically menu option must be selected. When editing models, the editor tabs will display a * to indicate that the model has unsaved changes.

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2.2. Role Mapping In order to convert the Principals in a Subject into a set of roles used for authorization, a PrincipalRoleMapper must be specified in the global configuration. Red Hat JBoss Data Grid ships with three mappers, and also allows you to provide a custom mapper. Table 2.3. Mappers Mapper Name Java XML Description IdentityRoleMapper org.infinispan.security.impl.IdentityRoleMapper <identity-role-mapper /> Uses the Principal name as the role name. CommonNameRoleMapper org.infinispan.security.impl.CommonRoleMapper <common-name-role-mapper /> If the Principal name is a Distinguished Name (DN), this mapper extracts the Common Name (CN) and uses it as a role name. For example the DN cn=managers,ou=people,dc=example,dc=com will be mapped to the role managers . ClusterRoleMapper org.infinispan.security.impl.ClusterRoleMapper <cluster-role-mapper /> Uses the ClusterRegistry to store principal to role mappings. This allows the use of the CLI's GRANT and DENY commands to add/remove roles to a Principal. Custom Role Mapper <custom-role-mapper class="a.b.c" /> Supply the fully-qualified class name of an implementation of org.infinispan.security.impl.PrincipalRoleMapper Report a bug

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7.9. at 7.9.1. RHBA-2015:0240 - at bug fix update Updated at packages that fix two bugs are now available for Red Hat Enterprise Linux 6. The at packages provide a utility for time-oriented job control. The at utility reads commands from standard input or from a specified file and allows you to specify that the commands will be run at a particular time. Bug Fixes BZ# 994201 Due to incorrect race condition handling in the "atd" daemon, "atd" terminated unexpectedly. With this update, "atd" handles the race condition correctly, so that now "atd" no longer terminates in the described scenario. BZ# 1166882 Previously, the "at" command was not properly checking the return value of the fclose() function call. As a consequence, if the /var/spool/at file system filled up, "at" could leave empty stale files in the spool directory. With this update, "at" properly checks the return value from fclose(), and "at" no longer leaves empty files in spool in the described scenario. Users of at are advised to upgrade to these updated packages, which fix these bugs.

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Appendix A. RHEL 7 repositories Before the upgrade, ensure you have appropriate repositories enabled as described in step 4 of the procedure in Preparing a RHEL 7 system for the upgrade . If you plan to use Red Hat Subscription Manager during the upgrade, you must enable the following repositories before the upgrade by using the subscription-manager repos --enable repository_id command: Architecture Repository Repository ID 64-bit Intel Base rhel-7-server-rpms Extras rhel-7-server-extras-rpms IBM POWER8 (little endian) Base rhel-7-for-power-le-rpms Extras rhel-7-for-power-le-extras-rpms IBM Z Base rhel-7-for-system-z-rpms Extras rhel-7-for-system-z-extras-rpms You can enable the following repositories before the upgrade by using the subscription-manager repos --enable repository_id command: Architecture Repository Repository ID 64-bit Intel Optional rhel-7-server-optional-rpms Supplementary rhel-7-server-supplementary-rpms IBM POWER8 (little endian) Optional rhel-7-for-power-le-optional-rpms Supplementary rhel-7-for-power-le-supplementary-rpms IBM Z Optional rhel-7-for-system-z-optional-rpms Supplementary rhel-7-for-system-z-supplementary-rpms Note If you have enabled a RHEL 7 Optional or a RHEL 7 Supplementary repository before an in-place upgrade, Leapp enables the RHEL 8 CodeReady Linux Builder or RHEL 8 Supplementary repositories, respectively. If you decide to use custom repositories, enable them per instructions in Configuring custom repositories .

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Chapter 9. Configuring Desktop with GSettings and dconf 9.1. Terminology Explained: GSettings, gsettings, and dconf This section defines several terms that are easily confused. dconf dconf is a key-based configuration system which manages user settings. It is the back end for GSettings used in Red Hat Enterprise Linux 7. dconf manages a range of different settings, including GDM , application, and proxy settings. dconf The dconf command-line utility is used for reading and writing individual values or entire directories from and to a dconf database. GSettings GSettings is a high-level API for application settings, front end for dconf . gsettings The gsettings command-line tool is used to view and change user settings.

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4.196. nfs-utils-lib 4.196.1. RHBA-2011:1750 - nfs-utils-lib bug fix update Updated nfs-utils-lib packages that fix one bug are now available for Red Hat Enterprise Linux 6. The nfs-utils-lib packages contain support libraries required by programs in the nfs-utils package. Bug Fix BZ# 711210 Prior to this update, libnfsidmap did not support ldap. With this update, nfs-utils-lib provides ldap support. All users of nfs-utils-lib are advised to upgrade to these updated packages, which fix this bug.

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E.3.3. /proc/bus/pci Later versions of the 2.6 Linux kernel have obsoleted the /proc/pci directory in favor of the /proc/bus/pci directory. Although you can get a list of all PCI devices present on the system using the command cat /proc/bus/pci/devices , the output is difficult to read and interpret. For a human-readable list of PCI devices, run the following command: The output is a sorted list of all IRQ numbers and addresses as seen by the cards on the PCI bus instead of as seen by the kernel. Beyond providing the name and version of the device, this list also gives detailed IRQ information so an administrator can quickly look for conflicts.

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~]# /sbin/lspci -vb 00:00.0 Host bridge: Intel Corporation 82X38/X48 Express DRAM Controller Subsystem: Hewlett-Packard Company Device 1308 Flags: bus master, fast devsel, latency 0 Capabilities: [e0] Vendor Specific Information <?> Kernel driver in use: x38_edac Kernel modules: x38_edac 00:01.0 PCI bridge: Intel Corporation 82X38/X48 Express Host-Primary PCI Express Bridge (prog-if 00 [Normal decode]) Flags: bus master, fast devsel, latency 0 Bus: primary=00, secondary=01, subordinate=01, sec-latency=0 I/O behind bridge: 00001000-00001fff Memory behind bridge: f0000000-f2ffffff Capabilities: [88] Subsystem: Hewlett-Packard Company Device 1308 Capabilities: [80] Power Management version 3 Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit- Capabilities: [a0] Express Root Port (Slot+), MSI 00 Capabilities: [100] Virtual Channel <?> Capabilities: [140] Root Complex Link <?> Kernel driver in use: pcieport Kernel modules: shpchp 00:1a.0 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #4 (rev 02) (prog-if 00 [UHCI]) Subsystem: Hewlett-Packard Company Device 1308 Flags: bus master, medium devsel, latency 0, IRQ 5 I/O ports at 2100 Capabilities: [50] PCI Advanced Features Kernel driver in use: uhci_hcd [output truncated]
Network APIs OpenShift Container Platform 4.13 Reference guide for network APIs Red Hat OpenShift Documentation Team

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Name: "mysvc", Subsets: [ { Addresses: [{"ip": "10.10.1.1"}, {"ip": "10.10.2.2"}], Ports: [{"name": "a", "port": 8675}, {"name": "b", "port": 309}] }, { Addresses: [{"ip": "10.10.3.3"}], Ports: [{"name": "a", "port": 93}, {"name": "b", "port": 76}] }, ]
Name: "mysvc", Subsets: [ { Addresses: [{"ip": "10.10.1.1"}, {"ip": "10.10.2.2"}], Ports: [{"name": "a", "port": 8675}, {"name": "b", "port": 309}] }, { Addresses: [{"ip": "10.10.3.3"}], Ports: [{"name": "a", "port": 93}, {"name": "b", "port": 76}] }, ]
{ Addresses: [{"ip": "10.10.1.1"}, {"ip": "10.10.2.2"}], Ports: [{"name": "a", "port": 8675}, {"name": "b", "port": 309}] }
a: [ 10.10.1.1:8675, 10.10.2.2:8675 ], b: [ 10.10.1.1:309, 10.10.2.2:309 ]
3.15. Searching for Virtual Machines The following table describes all search options for virtual machines. Note Currently, the Network Label , Custom Emulated Machine , and Custom CPU Type properties are not supported search parameters. Table 3.11. Searching for Virtual Machines Property (of resource or resource-type) Type Description (Reference) Hosts. hosts-prop Depends on property type The property of the hosts associated with the virtual machine. Templates. templates-prop Depends on property type The property of the templates associated with the virtual machine. Events. events-prop Depends on property type The property of the events associated with the virtual machine. Users. users-prop Depends on property type The property of the users associated with the virtual machine. Storage. storage-prop Depends on the property type The property of storage devices associated with the virtual machine. Vnic. vnic-prop Depends on the property type The property of the VNIC associated with the virtual machine. name String The name of the virtual machine. status List The availability of the virtual machine. ip Integer The IP address of the virtual machine. uptime Integer The number of minutes that the virtual machine has been running. domain String The domain (usually Active Directory domain) that groups these machines. os String The operating system selected when the virtual machine was created. creationdate Date The date on which the virtual machine was created. address String The unique name that identifies the virtual machine on the network. cpu_usage Integer The percent of processing power used. mem_usage Integer The percentage of memory used. network_usage Integer The percentage of network used. memory Integer The maximum memory defined. apps String The applications currently installed on the virtual machine. cluster List The cluster to which the virtual machine belongs. pool List The virtual machine pool to which the virtual machine belongs. loggedinuser String The name of the user currently logged in to the virtual machine. tag List The tags to which the virtual machine belongs. datacenter String The data center to which the virtual machine belongs. type List The virtual machine type (server or desktop). quota String The name of the quota associated with the virtual machine. description String Keywords or text describing the virtual machine, optionally used when creating the virtual machine. sortby List Sorts the returned results by one of the resource properties. page Integer The page number of results to display. next_run_configuration_exists Boolean The virtual machine has pending configuration changes. Example Vms: template.name = Win* and user.name = "" This example returns a list of virtual machines whose base template name begins with Win and are assigned to any user. Example Vms: cluster = Default and os = windows7 This example returns a list of virtual machines that belong to the Default cluster and are running Windows 7.

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Installing with RHEL image mode Red Hat build of MicroShift 4.18 Embedding MicroShift in a bootc image Red Hat OpenShift Documentation Team

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FROM registry.redhat.io/rhel9/rhel-bootc:9.4 ARG USHIFT_VER=4.17 RUN dnf config-manager --set-enabled rhocp-USD{USHIFT_VER}-for-rhel-9-USD(uname -m)-rpms --set-enabled fast-datapath-for-rhel-9-USD(uname -m)-rpms RUN dnf install -y firewalld microshift && systemctl enable microshift && dnf clean all Create a default 'redhat' user with the specified password. Add it to the 'wheel' group to allow for running sudo commands. ARG USER_PASSWD RUN if [ -z "USD{USER_PASSWD}" ] ; then echo USER_PASSWD is a mandatory build argument && exit 1 ; fi RUN useradd -m -d /var/home/redhat -G wheel redhat && echo "redhat:USD{USER_PASSWD}" | chpasswd Mandatory firewall configuration RUN firewall-offline-cmd --zone=public --add-port=22/tcp && firewall-offline-cmd --zone=trusted --add-source=10.42.0.0/16 && firewall-offline-cmd --zone=trusted --add-source=169.254.169.1 Create a systemd unit to recursively make the root filesystem subtree shared as required by OVN images RUN cat > /etc/systemd/system/microshift-make-rshared.service <<'EOF' [Unit] Description=Make root filesystem shared Before=microshift.service ConditionVirtualization=container [Service] Type=oneshot ExecStart=/usr/bin/mount --make-rshared / [Install] WantedBy=multi-user.target EOF RUN systemctl enable microshift-make-rshared.service
PULL_SECRET=~/.pull-secret.json USER_PASSWD=<your_redhat_user_password> 1 IMAGE_NAME=microshift-4.17-bootc sudo podman build --authfile "USD{PULL_SECRET}" -t "USD{IMAGE_NAME}" --build-arg USER_PASSWD="USD{USER_PASSWD}" -f Containerfile
sudo podman images "USD{IMAGE_NAME}"
REPOSITORY TAG IMAGE ID CREATED SIZE localhost/microshift-4.17-bootc latest 193425283c00 2 minutes ago 2.31 GB
REGISTRY_URL=quay.io sudo podman login "USD{REGISTRY_URL}" 1
REGISTRY_IMG=<myorg/mypath>/"USD{IMAGE_NAME}" 1 2 IMAGE_NAME=<microshift-4.17-bootc> 3 sudo podman push localhost/"USD{IMAGE_NAME}" "USD{REGISTRY_URL}/USD{REGISTRY_IMG}"
Chapter 14. Backup and restore 14.1. Backing up and restoring virtual machines You back up and restore virtual machines by using the OpenShift API for Data Protection (OADP) . Important OADP for OpenShift Virtualization is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process. For more information about the support scope of Red Hat Technology Preview features, see Technology Preview Features Support Scope . Prerequisites Access to the cluster as a user with the cluster-admin role. Procedure Install the OADP Operator according to the instructions for your storage provider. Install the Data Protection Application with the kubevirt and openshift plugins . Back up virtual machines by creating a Backup custom resource (CR) . Restore the Backup CR by creating a Restore CR . 14.1.1. Additional resources OADP features and plugins Troubleshooting

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function::cmdline_arg Name function::cmdline_arg - Fetch a command line argument. Synopsis Arguments n Argument to get (zero is the command itself) General Syntax cmdline_arg:string(n:long) Description Returns argument the requested argument from the current process or the empty string when there are not that many arguments or there is a problem retrieving the argument. Argument zero is traditionally the command itself.

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function cmdline_arg:string(n:long)
Part III. The Red Hat Build of OptaPlanner solver Solving a planning problem with OptaPlanner consists of the following steps: Model your planning problem as a class annotated with the @PlanningSolution annotation (for example, the NQueens class). Configure a Solver (for example a First Fit and Tabu Search solver for any NQueens instance). Load a problem data set from your data layer (for example a Four Queens instance). That is the planning problem. Solve it with Solver.solve(problem) , which returns the best solution found.

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Chapter 5. RHEL for Real Time processes and threads The RHEL for Real Time key factors in operating systems are minimal interrupt latency and minimal thread switching latency. Although all programs use threads and processes, RHEL for Real Time handles them in a different way compared to the standard Red Hat Enterprise Linux. In real-time, using parallelism helps achieve greater efficiency in task execution and latency. Parallelism is when multiple tasks or several sub-tasks run at the same time using the multi-core infrastructure of CPU. 5.1. Processes A real-time process, in simplest terms, is a program in execution. The term process refers to an independent address space, potentially containing multiple threads. When the concept of more than one process running inside one address space was developed, Linux turned to a process structure that shares an address space with another process. This works well, as long as the process data structure is small. A UNIX(R)-style process construct contains: Address mappings for virtual memory. An execution context (PC, stack, registers). State and accounting information. In real-time, each process starts with a single thread, often called the parent thread. You can create additional threads from parent threads using the fork() system calls. fork() creates a new child process which is identical to the parent process except for the new process identifier. The child process runs independent of the creating process. The parent and child processes can be executed simultaneously. The difference between the fork() and exec() system calls is that, fork() starts a new process which is the copy of the parent process and exec() replaces the current process image with the new one. In real-time, the fork() system call, when successful, returns the process identifier of the child process and the parent process returns a non-zero value. On error, it returns an error number. 5.2. Threads In real-time, multiple threads can exist within a process. All threads of a process share its virtual address space and system resources. A thread is a schedulable entity that contains: A program counter (PC). A register context. A stack pointer. In real-time, following are potential mechanisms to create parallelism: Using the fork() and exec() function calls to create new processes. The fork() call creates an exact duplicate of a process from which it is called and has a unique process identifier. Using the Posix threads ( pthreads ) API to create new threads within an already running process. You must evaluate the component interaction level before forking real-time threads. Creating a new address space and running it as a new process is beneficial when the components are independent of one another or with less interaction. When components are required to share data or communicate frequently, running the threads within one address space is more efficient. In real-time, the fork() system call, when successful, returns a zero value. On error, it returns an error number. 5.3. Additional resources fork(2)`and `exec(2) man pages on your system

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