mtpti5iD/redhat-docs_dataset huggingface dataset:
5.4.16.6. Splitting off a RAID Image as a Separate Logical Volume You can split off an image of a RAID logical volume to form a new logical volume. The procedure for splitting off a RAID image is the same as the procedure for splitting off a redundant image of a mirrored logical volume, as described in Section 5.4.3.2, "Splitting Off a Redundant Image of a Mirrored Logical Volume" . The format of the command to split off a RAID image is as follows: Just as when you are removing a RAID images from an existing RAID1 logical volume (as described in Section 5.4.16.5, "Changing the Number of Images in an Existing RAID1 Device" ), when you remove a RAID data subvolume (and its associated metadata subvolume) from the middle of the device, any higher numbered images will be shifted down to fill the slot. The index numbers on the logical volumes that make up a RAID array will thus be an unbroken sequence of integers. Note You cannot split off a RAID image if the RAID1 array is not yet in sync. The following example splits a 2-way RAID1 logical volume, my_lv , into two linear logical volumes, my_lv and new . The following example splits a 3-way RAID1 logical volume, my_lv , into a 2-way RAID1 logical volume, my_lv , and a linear logical volume, new

Commands:
lvconvert --splitmirrors count -n splitname vg/lv [ removable_PVs ]
lvs -a -o name,copy_percent,devices my_vg LV Copy% Devices my_lv 12.00 my_lv_rimage_0(0),my_lv_rimage_1(0) [my_lv_rimage_0] /dev/sde1(1) [my_lv_rimage_1] /dev/sdf1(1) [my_lv_rmeta_0] /dev/sde1(0) [my_lv_rmeta_1] /dev/sdf1(0) lvconvert --splitmirror 1 -n new my_vg/my_lv lvs -a -o name,copy_percent,devices my_vg LV Copy% Devices my_lv /dev/sde1(1) new /dev/sdf1(1)
lvs -a -o name,copy_percent,devices my_vg LV Copy% Devices my_lv 100.00 my_lv_rimage_0(0),my_lv_rimage_1(0),my_lv_rimage_2(0) [my_lv_rimage_0] /dev/sde1(1) [my_lv_rimage_1] /dev/sdf1(1) [my_lv_rimage_2] /dev/sdg1(1) [my_lv_rmeta_0] /dev/sde1(0) [my_lv_rmeta_1] /dev/sdf1(0) [my_lv_rmeta_2] /dev/sdg1(0) lvconvert --splitmirror 1 -n new my_vg/my_lv lvs -a -o name,copy_percent,devices my_vg LV Copy% Devices my_lv 100.00 my_lv_rimage_0(0),my_lv_rimage_1(0) [my_lv_rimage_0] /dev/sde1(1) [my_lv_rimage_1] /dev/sdf1(1) [my_lv_rmeta_0] /dev/sde1(0) [my_lv_rmeta_1] /dev/sdf1(0) new /dev/sdg1(1)
Appendix A. Revision History Revision History Revision 4-4 Tue Apr 18 2017 Steven Levine Update to version for 6.9 GA publication. Revision 4-3 Wed Mar 8 2017 Steven Levine Version for 6.9 GA publication. Revision 4-1 Fri Dec 16 2016 Steven Levine Version for 6.9 Beta publication. Revision 3-4 Tue Apr 26 2016 Steven Levine Preparing document for 6.8 GA publication. Revision 3-3 Wed Mar 9 2016 Steven Levine Initial revision for Red Hat Enterprise Linux 6.8 Beta release Revision 2-3 Wed Jul 22 2015 Steven Levine Rebuild for Red Hat Enterprise Linux 6.7 Revision 2-2 Wed Jul 8 2015 Steven Levine Initial Revision for Red Hat Enterprise Linux 6.7 Revision 2-1 Mon Apr 3 2015 Steven Levine Initial revision for Red Hat Enterprise Linux 6.7 Beta release Revision 1-13 Wed Oct 8 2014 Steven Levine Initial Revision for Red Hat Enterprise Linux 6.6 Revision 1-12 Thu Aug 7 2014 Steven Levine Initial revision for Red Hat Enterprise Linux 6.6 Beta release Revision 1-7 Wed Nov 20 2013 John Ha Initial Revision for Red Hat Enterprise Linux 6.5 Revision 1-4 Mon Feb 18 2013 John Ha Initial Revision for Red Hat Enterprise Linux 6.4 Revision 1-3 Mon Jun 18 2012 John Ha Initial Revision for Red Hat Enterprise Linux 6.3 Revision 1-2 Fri Aug 26 2011 John Ha Initial Revision for Red Hat Enterprise Linux 6.2 Revision 1-1 Wed Nov 10 2010 Paul Kennedy Initial revision for Red Hat Enterprise Linux 6 release

Commands:
4.4.2. Additional Options for the virsh migrate Command In addition to --live , virsh migrate accepts the following options: --direct - used for direct migration --p2p - used for peer-to-peer migration --tunnelled - used for tunneled migration --persistent - leaves the domain in a persistent state on the destination host physical machine --undefinesource - removes the guest virtual machine on the source host physical machine --suspend - leaves the domain in a paused state on the destination host physical machine --change-protection - enforces that no incompatible configuration changes will be made to the domain while the migration is underway; this option is implicitly enabled when supported by the hypervisor, but can be explicitly used to reject the migration if the hypervisor lacks change protection support. --unsafe - forces the migration to occur, ignoring all safety procedures. --verbose - displays the progress of migration as it is occurring --abort-on-error - cancels the migration if a soft error (such as an I/O error) happens during the migration process. --migrateuri - the migration URI which is usually omitted. --domain [string] - domain name, id or uuid --desturi [string] - connection URI of the destination host physical machine as seen from the client(normal migration) or source(p2p migration) --migrateuri - migration URI, usually can be omitted --timeout [seconds] - forces a guest virtual machine to suspend when the live migration counter exceeds N seconds. It can only be used with a live migration. Once the timeout is initiated, the migration continues on the suspended guest virtual machine. --dname [string] - changes the name of the guest virtual machine to a new name during migration (if supported) --xml - the filename indicated can be used to supply an alternative XML file for use on the destination to supply a larger set of changes to any host-specific portions of the domain XML, such as accounting for naming differences between source and destination in accessing underlying storage. This option is usually omitted. Refer to the virsh man page for more information.

Commands:
Chapter 3. Installing kdump The kdump service is installed and activated by default on the new versions of RHEL 9 installations. 3.1. What is kdump kdump is a service that provides a crash dumping mechanism and generates a crash dump or a vmcore dump file. vmcore includes the contents of the system memory for analysis and troubleshooting. kdump uses the kexec system call to boot into the second kernel, capture kernel , without a reboot. This kernel captures the contents of the crashed kernel's memory and saves it into a file. The second kernel is available in a reserved part of the system memory. Important A kernel crash dump can be the only information available if a system failure occur. Therefore, operational kdump is important in mission-critical environments. Red Hat advises to regularly update and test kexec-tools in your normal kernel update cycle. This is important when you install new kernel features. If you have multiple kernels on a machine, you can enable kdump for all installed kernels or for specified kernels only. When you install kdump , the system creates a default /etc/kdump.conf file. /etc/kdump.conf includes the default minimum kdump configuration, which you can edit to customize the kdump configuration. 3.2. Installing kdump using Anaconda The Anaconda installer provides a graphical interface screen for kdump configuration during an interactive installation. You can enable kdump and reserve the required amount of memory. Procedure On the Anaconda installer, click KDUMP and enable kdump : In Kdump Memory Reservation , select Manual ` if you must customize the memory reserve. In KDUMP > Memory To Be Reserved (MB) , set the required memory reserve for kdump . = Installing kdump on the command line Installation options such as custom Kickstart installations, in some cases does not install or enable kdump by default. The following procedure helps you enable kdump in this case. Prerequisites An active RHEL subscription. A repository containing the kexec-tools package for your system CPU architecture. Fulfilled requirements for kdump configurations and targets. For details, see Supported kdump configurations and targets . Procedure Check if kdump is installed on your system: Output if the package is installed: Output if the package is not installed: Install kdump and other necessary packages:

Commands:
rpm -q kexec-tools
kexec-tools-2.0.22-13.el9.x86_64
package kexec-tools is not installed
dnf install kexec-tools
Chapter 2. Removed features The following features are no longer available in 7.9: OpenJ9 images The IBM Z (s390x) and IBM Power Systems (ppc64le) images based on OpenJ9 are no longer supported. Newer images for those platforms are based on OpenJDK. Template based installations The use of application templates for deploying AMQ Broker on OpenShift Container Platform was deprecated in releases and is now removed. Use the AMQ Broker Operator as described in Deploying AMQ Broker on OpenShift Container Platform using the AMQ Broker Operator . OpenShift Container Platform 3.11 Deploying AMQ Broker on OpenShift Container Platform 3.11 is no longer supported. AMQ Broker is supported on OpenShift Container Platform 4.6, 4.7 or 4.8. RHEL 7 based images All deployments of AMQ Broker on OpenShift Container Platform now use RHEL 8 based images. Documentation The Using JON with AMQ Broker guide is no longer published as part of the AMQ Broker documentation. However, you can still access the last published version as part of the AMQ Broker 7.8 documentation .

Commands:
6.3. Splitting a Volume Group In this example, an existing volume group consists of three physical volumes. If there is enough unused space on the physical volumes, a new volume group can be created without adding new disks. In the initial set up, the logical volume mylv is carved from the volume group myvol , which in turn consists of the three physical volumes, /dev/sda1 , /dev/sdb1 , and /dev/sdc1 . After completing this procedure, the volume group myvg will consist of /dev/sda1 and /dev/sdb1 . A second volume group, yourvg , will consist of /dev/sdc1 . 6.3.1. Determining Free Space You can use the pvscan command to determine how much free space is currently available in the volume group.

Commands:
pvscan PV /dev/sda1 VG myvg lvm2 [17.15 GB / 0 free] PV /dev/sdb1 VG myvg lvm2 [17.15 GB / 12.15 GB free] PV /dev/sdc1 VG myvg lvm2 [17.15 GB / 15.80 GB free] Total: 3 [51.45 GB] / in use: 3 [51.45 GB] / in no VG: 0 [0 ]
Chapter 5. Managing subscriptions in the web console You can manage your Red Hat product subscriptions in the Red Hat Enterprise Linux 9 web console. Prerequisites Your Red Hat Customer Portal or a subscription activation key. 5.1. Subscription management in the web console The RHEL 9 web console provides an interface for using Red Hat Subscription Manager installed on your local system. The Subscription Manager connects to the Red Hat Customer Portal and verifies available: Active subscriptions Expired subscriptions Renewed subscriptions If you want to renew the subscription or get a different one on the Red Hat Customer Portal, you do not have to update the Subscription Manager data manually. The Subscription Manager synchronizes data with the Red Hat Customer Portal automatically. 5.2. Registering subscriptions with credentials in the web console You can register a newly installed Red Hat Enterprise Linux with your account credentials in the RHEL web console. Prerequisites A valid user account on the Red Hat Customer Portal. See the Create a Red Hat Login page. An active subscription for your RHEL system. You have installed the RHEL 9 web console. For instructions, see Installing and enabling the web console . Procedure Log in to the RHEL 9 web console. For details, see Logging in to the web console . In the Health filed in the Overview page, click the Not registered warning, or click Subscriptions in the main menu to move to page with your subscription information. In the Overview field, click Register . In the Register system dialog box, select Account to register by using your account credentials. Enter your username. Enter your password. Optional: Enter your organization's name or ID. If your account belongs to more than one organization on the Red Hat Customer Portal, you must add the organization name or organization ID. To get the org ID, go to your Red Hat contact point. If you do not want to connect your system to Red Hat Insights, clear the Insights check box. Click Register . 5.3. Registering subscriptions with activation keys in the web console You can register a newly installed Red Hat Enterprise Linux with an activation key in the RHEL web console. Prerequisites An activation key of your Red Hat product subscription. You have installed the RHEL 9 web console. For instructions, see Installing and enabling the web console . Procedure Log in to the RHEL 9 web console. For details, see Logging in to the web console . In the Health field on the Overview page, click the Not registered warning, or click Subscriptions in the main menu to move to the page with your subscription information. . In the Overview filed, click Register . In the Register system dialog box, select Activation key to register using an activation key. Enter your key or keys. Enter your organization's name or ID. To get the organization ID, go to your Red Hat contact point. If you do not want to connect your system to Red Hat Insights, clear the Insights check box. Click Register .

Commands:
Chapter 3. Managing cluster PVC size 3.1. Configuring the default PVC size for your cluster To configure how resources are claimed within your OpenShift AI cluster, you can change the default size of the cluster's persistent volume claim (PVC) ensuring that the storage requested matches your common storage workflow. PVCs are requests for resources in your cluster and also act as claim checks to the resource. Prerequisites You have logged in to OpenShift AI as a user with OpenShift AI administrator privileges. Note Changing the PVC setting restarts the Jupyter pod and makes Jupyter unavailable for up to 30 seconds. As a workaround, it is recommended that you perform this action outside of your organization's typical working day. Procedure From the OpenShift AI dashboard, click Settings Cluster settings . Under PVC size , enter a new size in gibibytes or mebibytes. Click Save changes . Verification New PVCs are created with the default storage size that you configured. Additional resources Understanding persistent storage 3.2. Restoring the default PVC size for your cluster To change the size of resources utilized within your OpenShift AI cluster, you can restore the default size of your cluster's persistent volume claim (PVC). Prerequisites You have logged in to OpenShift AI as a user with OpenShift AI administrator privileges. Procedure From the OpenShift AI dashboard, click Settings Cluster settings . Click Restore Default to restore the default PVC size of 20GiB. Click Save changes . Verification New PVCs are created with the default storage size of 20 GiB. Additional resources Understanding persistent storage (OpenShift Dedicated) Understanding persistent storage (Red Hat OpenShift Service on AWS)

Commands:
16.2. Registering a New Guest Virtual Machine In cases where a new guest virtual machine is to be created on a host that is already registered and running, the virt-who service must also be running. This ensures that the virt-who service maps the guest to a hypervisor, so the system is properly registered as a virtual system. To register the virtual machine, run the following command as root in a terminal:

Commands:
subscription-manager register --username=admin --password=secret --auto-attach
Chapter 9. Validating schemas with Service Registry You can use Red Hat Service Registry with AMQ Streams. Service Registry is a datastore for sharing standard event schemas and API designs across API and event-driven architectures. You can use Service Registry to decouple the structure of your data from your client applications, and to share and manage your data types and API descriptions at runtime using a REST interface. Service Registry stores schemas used to serialize and deserialize messages, which can then be referenced from your client applications to ensure that the messages that they send and receive are compatible with those schemas. Service Registry provides Kafka client serializers/deserializers for Kafka producer and consumer applications. Kafka producer applications use serializers to encode messages that conform to specific event schemas. Kafka consumer applications use deserializers, which validate that the messages have been serialized using the correct schema, based on a specific schema ID. You can enable your applications to use a schema from the registry. This ensures consistent schema usage and helps to prevent data errors at runtime. Additional resources Service Registry documentation Service Registry is built on the Apicurio Registry open source community project available on GitHub: Apicurio/apicurio-registry

Commands:
Chapter 5. LVM Configuration Examples This chapter provides some basic LVM configuration examples. 5.1. Creating an LVM Logical Volume on Three Disks This example procedure creates an LVM logical volume called new_logical_volume that consists of the disks at /dev/sda1 , /dev/sdb1 , and /dev/sdc1 . To use disks in a volume group, label them as LVM physical volumes with the pvcreate command. Warning This command destroys any data on /dev/sda1 , /dev/sdb1 , and /dev/sdc1 . Create the a volume group that consists of the LVM physical volumes you have created. The following command creates the volume group new_vol_group . You can use the vgs command to display the attributes of the new volume group. Create the logical volume from the volume group you have created. The following command creates the logical volume new_logical_volume from the volume group new_vol_group . This example creates a logical volume that uses 2 gigabytes of the volume group. Create a file system on the logical volume. The following command creates a GFS2 file system on the logical volume. The following commands mount the logical volume and report the file system disk space usage.

Commands:
pvcreate /dev/sda1 /dev/sdb1 /dev/sdc1 Physical volume "/dev/sda1" successfully created Physical volume "/dev/sdb1" successfully created Physical volume "/dev/sdc1" successfully created
vgcreate new_vol_group /dev/sda1 /dev/sdb1 /dev/sdc1 Volume group "new_vol_group" successfully created
vgs VG #PV #LV #SN Attr VSize VFree new_vol_group 3 0 0 wz--n- 51.45G 51.45G
lvcreate -L 2G -n new_logical_volume new_vol_group Logical volume "new_logical_volume" created
mkfs.gfs2 -p lock_nolock -j 1 /dev/new_vol_group/new_logical_volume This will destroy any data on /dev/new_vol_group/new_logical_volume. Are you sure you want to proceed? [y/n] y Device: /dev/new_vol_group/new_logical_volume Blocksize: 4096 Filesystem Size: 491460 Journals: 1 Resource Groups: 8 Locking Protocol: lock_nolock Lock Table: Syncing All Done
mount /dev/new_vol_group/new_logical_volume /mnt df Filesystem 1K-blocks Used Available Use% Mounted on /dev/new_vol_group/new_logical_volume 1965840 20 1965820 1% /mnt
1.10. Connecting to a VDB Using the Data Source Class The org.teiid.jdbc.TeiidDataSource class is based on the javax.sql.DataSource connection factory. It can be used to create ManagedConnection s and XAConnection s to both DataSource s and XADataSource s. XA transactions are extended to JBoss Data Virtualization sources that support XA. The JBoss Data Virtualization DataSource class is serializable and can be used with JNDI naming services. See EAP_HOME /quickstarts/simpleclient/ example for more information.

Commands:
2.2.2. Enabling IP Ports on Computers That Run luci To allow client computers to communicate with a computer that runs luci (the Conga user interface server), and to allow a computer that runs luci to communicate with ricci in the cluster nodes, you must enable the IP ports assigned to luci and ricci . Table 2.2, "Enabled IP Ports on a Computer That Runs luci " lists the IP port numbers, their respective protocols, the components to which the port numbers are assigned, and references to iptables rule examples. At each computer that runs luci , enable IP ports according to Table 2.1, "Enabled IP Ports on Red Hat Cluster Nodes" . (All examples are in Section 2.2.3, "Examples of iptables Rules" .) Note If a cluster node is running luci , port 11111 should already have been enabled. Table 2.2. Enabled IP Ports on a Computer That Runs luci IP Port Number Protocol Component Reference to Example of iptables Rules 8084 TCP luci (Conga user interface server) Example 2.2, "Port 8084: luci (Cluster Node or Computer Running luci )" 11111 TCP ricci (Conga remote agent) Example 2.3, "Port 11111: ricci (Cluster Node and Computer Running luci )"

Commands:
4.16. Removing Data Securely Using scrub The scrub utility sets patterns on special files or disk devices to make retrieving data more difficult. Using scrub is faster than writing random data on a disk. This process provides high availability, reliability, and data protection. To start using the scrub command, install the scrub package: The scrub utility operates in one of the following basic modes: Character or Block Device The special file corresponding to a whole disk is scrubbed and all data on it, is destroyed. This is the most effective method. File A regular file is scrubbed and only the data in the file is destroyed. Directory With the -X option, a directory is created and filled with files until the file system is full. Then, the files are scrubbed as in file mode. Example 4.7. Scrubbing a Raw Device To scrub a raw device /dev/sdf1 with default National Nuclear Security Administration (NNSA) patterns, enter the following command: Example 4.8. Scrubbing a File Create a 1MB file: Show the file size: Show the contents of the file: Scrub the file: Verify that the file contents have been scrubbed: Verify that the file size remains the same: For more information on scrub modes, options, methods, and caveats, see the scrub (1) man page.

Commands:
~]# yum install scrub
scrub [OPTIONS] special file
scrub [OPTIONS] file
scrub -X [OPTIONS] directory
~]# scrub /dev/sdf1 scrub: using NNSA NAP-14.1-C patterns scrub: please verify that device size below is correct! scrub: scrubbing /dev/sdf1 1995650048 bytes (~1GB) scrub: random |................................................| scrub: random |................................................| scrub: 0x00 |................................................| scrub: verify |................................................|
~]USD base64 /dev/urandom | head -c USD[ 1024*1024 ] > file.txt
~]USD ls -lh total 1.0M -rw-rw-r--. 1 username username 1.0M Sep 8 15:23 file.txt
~]USD head -1 file.txt JnNpaTEveB/IYsbM9lhuJdw+0jKhwCIBUsxLXLAyB8uItotUlNHKKUeS/7bCRKDogEP+yJm8VQkL
~]USD scrub file.txt scrub: using NNSA NAP-14.1-C patterns scrub: scrubbing file.txt 1048576 bytes (~1024KB) scrub: random |................................................| scrub: random |................................................| scrub: 0x00 |................................................| scrub: verify |................................................|
~]USD cat file.txt SCRUBBED!
~]USD ls -lh total 1.0M -rw-rw-r--. 1 username username 1.0M Sep 8 15:24 file.txt