Oracle Linux 8

https://docs.oracle.com/en/operating-systems/oracle-linux/8/
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### Configure Boot Loader Options

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/install/install-ConfiguringtheBootLoader.html

Example of specifying installation repository and Kickstart file locations via the boot command line.

```text
inst.repo=nfs:nfs.example.com:/ISOs/OL8/full_image.iso \
inst.ks=nfs:nfs.example.com:/kickstart/OL8/server-ks.cfg ip=dhcp
```

--------------------------------

### Install and Enable Watchdog Service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/kvm-user/kvm-config_vm_watchdog.html

Use these commands to install the watchdog package and start the service on the guest OS.

```bash
sudo dnf install watchdog
sudo systemctl enable --now watchdog.service
```

--------------------------------

### Configure GRUB Boot Loader

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/install/install-ConfiguringPXEBootLoading.html

Example configuration for the grub.cfg file to support both network installation and local booting.

```text
set default 0
set timeout=10

menuentry 'ol8 localboot' {
echo "Booting from local disk"
set root=(hd0,gpt1)
chainloader efi/shim.efi
boot
}

menuentry 'ol8' {
  echo "Loading vmlinuz"
  linuxefi vmlinuz inst.repo=/var/nfs-exports/ISOs/ol8/ inst.ks.sendmac \
  inst.ks=/var/nfs-exports/ISOs/ksfiles/kstart-file
  echo "Loading /initrd.img"
  initrdefi initrd.img
  echo "Booting installation kernel"
}
```

--------------------------------

### Setup and Start Quorum Device Service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/availability/availability-InstallingandEnablingaQuorumDevice.html

Configure the host to use the net model and start the quorum device service.

```bash
sudo pcs qdev setup model net --enable --start
```

--------------------------------

### Define a Kickstart configuration file with Btrfs

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/install/install-AbouttheKickstartConfigurationFile.html

A complete Kickstart configuration example for Oracle Linux 8, demonstrating repository setup, Btrfs partitioning, and system settings.

```kickstart
#platform=x86, AMD64, or Intel EM64T
#version=OL8
# Firewall configuration
firewall --enabled --service=ssh
      
# Install OS instead of upgrade
install
      
# Use Oracle Linux yum server repositories as installation source
repo --name="ol8_AppStream" --baseurl="https://yum.oracle.com/repo/OracleLinux/OL8/appstream/x86_64/"
repo --name="ol8_UEKR7" --baseurl="https://yum.oracle.com/repo/OracleLinux/OL8/UEKR7/x86_64/"
url --url="https://yum.oracle.com/repo/OracleLinux/OL8/baseos/latest/x86_64"
      
# Root password
rootpw --iscrypted SHA512_password_hash
      
# Use graphical install
graphical
firstboot --disable
      
# Keyboard layouts
keyboard --vckeymap=us --xlayouts='us'
      
# System language
lang en_US.UTF-8
      
# SELinux configuration
selinux --enforcing
      
# Installation logging level
logging --level=info
      
# System timezone
timezone  America/Los_Angeles
      
# Network information
network  --bootproto=dhcp --device=em1 --onboot=yes --hostname=hostname
      
# System bootloader configuration
bootloader --location=mbr --boot-drive=sda
      
# Non-administrative user
user --name=user --homedir=/home/user --password=SHA512_password_hash --iscrypted
      
# Partition information
clearpart --all --initlabel --drives=sda
autopart --type=btrfs
```

--------------------------------

### Enable and start TuneD service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/tuned/installing_tuned.html

Use systemctl to enable the service to start at boot and immediately start the service.

```bourne
sudo systemctl enable --now tuned
```

--------------------------------

### Example Service Unit File Configuration

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/systemd/ModifyingsystemdConfigurationFiles.html

A template demonstrating the structure of a service unit file including Unit, Service, and Install sections.

```ini
[Unit]
Description=A test service used to develop a service unit file template

[Service]
Type=simple
StandardOutput=journal
ExecStart=/usr/lib/systemd/helloworld.sh

[Install]
WantedBy=default.target
```

--------------------------------

### Start a service with systemctl

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/systemd/StartingandStoppingServices.html

Initiates a service immediately using the start command.

```bash
sudo systemctl start sshd
```

--------------------------------

### Start a cloned KVM

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/kvm-user/kvm-CloningVirtualMachines.html

Starts the newly created KVM instance to verify it boots correctly.

```bash
virsh start My_KVM-clone
Domain 'My_KVM-clone' started
```

--------------------------------

### Enable and start a service immediately

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/systemd/EnablingandDisablingServices.html

Enables the service and starts it in the current session.

```bash
sudo systemctl enable --now httpd
```

--------------------------------

### Install guestfs-tools

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/kvm-user/kvm-CloningVirtualMachines.html

Installs the necessary tools for disk image preparation on the host system.

```bash
sudo dnf install guestfs-tools
```

--------------------------------

### Install binutils-gprofng

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/gprofng/installing_gprofng.html

Installs the gprofng profiling tool and its dependencies.

```bash
sudo dnf install -y binutils-gprofng
```

--------------------------------

### Install Snapper

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/btrfs/btrfs-UsingtheSnapperUtilityWithBtrfsSubvolumes.html

Install the Snapper utility using the dnf package manager.

```bash
sudo dnf install -y snapper
```

--------------------------------

### Install NGINX

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/balancing/balancing-SettingUpLoadBalancingbyUsingNGINX.html

Installs the NGINX package on the server.

```bash
sudo dnf install nginx
```

--------------------------------

### Install HAProxy

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/balancing/balancing-SettingUpLoadBalancingbyUsingHAProxy.html

Installs the HAProxy package on the front-end server.

```bash
sudo dnf install haproxy
```

--------------------------------

### Install blktrace package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/monitoring/using_blktrace_to_debug_block_volume_errors.html

Installs the blktrace utility on the system.

```bourne
sudo dnf install blktrace
```

--------------------------------

### Install PowerTOP package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/tuned/installing_powertop.html

Use this command to install the PowerTOP utility on your system.

```bourne
sudo dnf install powertop
```

--------------------------------

### Enable and Start Samba Service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/samba/configure-as-AD-member_task.html

Starts the smb service and ensures it is enabled to run on boot.

```bash
sudo systemctl enable --now smb
```

--------------------------------

### Install iSCSI initiator utilities

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/stordev/stordev-WorkingWithLinuxIOStorage.html

Installs the necessary package for iSCSI initiator functionality.

```bash
sudo dnf install iscsi-initiator-utils
```

--------------------------------

### Start OSWbb

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/monitoring/monitoring-RunningOSWbb.html

Execute the start script with optional frequency and duration parameters.

```bash
sudo ./startOSWbb.sh [frequency duration]
```

```bash
sudo ./startOSWbb.sh 60 12
```

--------------------------------

### Start the smb service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/samba/services_concept.html

Starts the smbd daemon for file and print sharing. Requires the samba package to be installed.

```bash
sudo systemctl start smb.service
```

--------------------------------

### Define Preinstallation Tasks

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/install/install-AbouttheKickstartConfigurationFile.html

Use the %pre section to execute scripts or download files before the installation begins. Ensure all referenced URLs or paths are accessible to the installer.

```kickstart
%pre
%include http://server-ip-address/scripts/config-partitions
wget -q -O- http://server-ip-address/scripts/package-list > /tmp/package-list
%end
```

--------------------------------

### Install SCAP Packages

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/oscap/oscap-SCAPPackages.html

Install the core OpenSCAP packages and the security guide using the dnf package manager.

```bash
sudo dnf install openscap openscap-utils scap-security-guide
```

--------------------------------

### OSWbb Startup Output

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/monitoring/monitoring-RunningOSWbb.html

Example output showing the discovery of system utilities and the initialization of data collection.

```text
...
Testing for discovery of OS Utilities...
VMSTAT found on your system.
IOSTAT found on your system.
MPSTAT found on your system.
IFCONFIG found on your system.
NETSTAT found on your system.
TOP found on your system.

Testing for discovery of OS CPU COUNT
oswbb is looking for the CPU COUNT on your system
CPU COUNT will be used by oswbba to automatically look for cpu problems

CPU COUNT found on your system.
CPU COUNT = 4

Discovery completed.

Starting OSWatcher Black Box v7.3.0  on date and time
With SnapshotInterval = 60
With ArchiveInterval = 12
...

Data is stored in directory: OSWbba_archive

Starting Data Collection...

oswbb heartbeat: date and time
oswbb heartbeat: date and time + 60 seconds
...
```

--------------------------------

### Define Postinstallation Tasks

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/install/install-AbouttheKickstartConfigurationFile.html

Use the %post section to run scripts after installation. The --nochroot option allows access to files outside the default chroot environment.

```kickstart
%post --nochroot
%include /tmp/post-config
%end
```

```kickstart
%post
wget -q -O- http://192.168.1.100/scripts/resolv.conf > /etc/resolv.conf
%include http://instsvr.example.com/scripts/post-config
.
.
.
%end
```

--------------------------------

### Start the winbind service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/samba/services_concept.html

Starts the winbindd daemon for resolving AD users and groups. Requires the samba-winbind package to be installed.

```bash
sudo systemctl start winbind.service
```

--------------------------------

### Create Oracle Linux 9 VM via URL and Kickstart

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/kvm-user/kvm-CreatingaNewVirtualMachine.html

Automates the installation from a remote URL using a provided Kickstart configuration file.

```bash
virt-install \
    --graphics vnc \
    --name ol9-guest-demo1 --memory 2048 --vcpus 2 --disk size=160 \
    --os-variant ol9.0 --location http://example.com/OS-install \
    --initrd-inject /home/uniquename/ks.cfg --extra-args="inst.ks=file:/ks.cfg console=tty0 console=ttyS0,115200n8"
```

--------------------------------

### Start ISO Image Build

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/ibldr/CreateISOImages.html

Initiate the creation of an ISO image using the specified blueprint.

```bash
sudo composer-cli compose start myblueprint image-installer
```

--------------------------------

### Start the nmb service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/samba/services_concept.html

Starts the nmbd daemon for NetBIOS name resolution and network browsing. Requires the samba package to be installed.

```bash
sudo systemctl start nmb.service
```

--------------------------------

### Example: Create Thin Pool and Volume

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/stordev/stordev-WorkingWithLogicalVolumeManager.html

Demonstrates creating a 1GB thin pool and a 2GB thinly provisioned volume.

```bash
`sudo lvcreate --size 1g --thin myvg/mytp`
Logical volume "mytp" created
```

```bash
`sudo lvcreate --virtualsize 2g --thin myvg/mytp --name mytv`
Logical volume "mytv" created
```

--------------------------------

### Start KVM Guest

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/kvm-user/kvm-network-topicgroup.html

Initiates the startup process for a specified KVM guest.

```bash
sudo virsh start GuestName
```

--------------------------------

### Verify gprofng installation

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/gprofng/installing_gprofng.html

Checks the installed version of gprofng to confirm successful installation.

```bash
gprofng --version
```

--------------------------------

### Start KVM Instance

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/kvm-user/kvm-start-stop-remove.html

Commands to start an inactive KVM instance on local or remote hosts.

```bash
sudo virsh start KVM_Guest_Name
```

```bash
Domain 'KVM_guest_name' started
```

```bash
sudo virsh -c qemu+ssh://root@host_ip_address/system start Remote_KVM_guest_name
```

```bash
root@host_ip-address's password:

Domain 'remote_KVM_guest_name' started
```

--------------------------------

### Enable and start the adaptivemmd service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/monitoring/using_the_adaptive_memory_management_daemon.html

Use systemctl to enable the daemon to start automatically and initiate it immediately.

```bourne
sudo systemctl enable --now adaptivemmd
```

--------------------------------

### Initialize DHCP Configuration Files

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/network/network-DHCPConfigContents.html

Commands to copy example configuration files to the active DHCP configuration directory.

```bash
cp /usr/share/doc/dhcp-server/dhcpd.conf.example /etc/dhcp/dhcpd.conf
```

```bash
cp /usr/share/doc/dhcp-server/dhcpd6.conf.example /etc/dhcp/dhcpd6.conf
```

--------------------------------

### Start Cluster Services on a Node

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/availability/availability-CreatingaServiceandTestingFailover.html

Use this command to manually start the cluster services on a specific node if they are not configured to start automatically on boot.

```bash
sudo pcs cluster start node1
```

--------------------------------

### Example kernel command line output

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/boot/boot-UsinggrubbyToManageKernels_check_last_kernel_cmdline.html

Sample output showing the kernel boot parameters, including root UUIDs and crash kernel settings.

```text
BOOT_IMAGE=(hd0,gpt2)/vmlinuz-5.15.0-208.159.3.2.el9uek.x86_64 
root=UUID=72dfa724-5feb-49e2-8869-40625bfebb01 ro 
resume=UUID=13078314-ebff-4c44-b18c-3445f6802198 
rd.luks.uuid=luks-a80f8f10-75b6-45de-b63e-64b8b6a3a94b 
rhgb quiet crashkernel=1G-64G:448M,64G-:512M
```

--------------------------------

### Install the Watchdog package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/boot/boot-ConfigWatchdogServ.html

Use the DNF package manager to install the necessary watchdog software on the system.

```bash
sudo dnf install watchdog
```

--------------------------------

### Install Keepalived

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/balancing/balancing-SettingUpLoadBalancingbyUsingKeepalived.html

Installs the keepalived package on the server.

```bash
sudo dnf install keepalived
```

--------------------------------

### TuneD Global Configuration File Example

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/tuned/reviewing_tuned_global_settings.html

Sample configuration file for /etc/tuned/tuned-main.conf showing common parameters like daemon mode, dynamic tuning, and intervals.

```ini
# Global tuned configuration file.

# Whether to use daemon. Without daemon it just applies tuning. It is
# not recommended, because many functions don't work without daemon,
# e.g. there will be no D-Bus, no rollback of settings, no hotplug,
# no dynamic tuning, ...
daemon = 1

# Dynamicaly tune devices, if disabled only static tuning will be used.
dynamic_tuning = 0

# How long to sleep before checking for events (in seconds)
# higher number means lower overhead but longer response time.
sleep_interval = 1

# Update interval for dynamic tunings (in seconds).
# It must be multiply of the sleep_interval.
update_interval = 10

# Recommend functionality, if disabled "recommend" command will be not
# available in CLI, daemon will not parse recommend.conf but will return
# one hardcoded profile (by default "balanced").
recommend_command = 1
...
```

--------------------------------

### Specify Local Kickstart File Location

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/install/install-StartingtheKickstartInstallation.html

Use this boot option to point the installer to a specific Kickstart configuration file located on local media.

```text
inst.ks=cdrom:/dev/sbd1/tmp/ks.cfg
```

--------------------------------

### Install cluster software packages

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/availability/availability-InstallingandEnablingthePacemakerandCorosyncService.html

Install the pcs, pacemaker, resource-agents, and fence-agents-all packages on each cluster node.

```bash
sudo dnf install pcs pacemaker resource-agents fence-agents-all
```

--------------------------------

### Display corelens output example

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/drgn/corelens_command_reference.html

Example output showing system information and mount points when running corelens on a live system.

```text
warning: Running corelens against a live system.
         Data may be inconsistent, or corelens may crash.
 
====== MODULE sys ======
MODE        : Live kernel
DATE        : Fri Jul 12 18:18:12 2024
NODENAME    : oracle-example-ol8
RELEASE     : 5.15.0-206.153.7.el8uek.x86_64
VERSION     : #2 SMP Thu May 9 15:52:29 PDT 2024
MACHINE     : x86_64
UPTIME      : 10 days, 0:35:16
LOAD AVERAGE: 0.12  ,  0.04 ,  0.01
JIFFIES     : 5160783970
MEMORY      : 7.47 GiB
TASKS       : 275 R:1 D:0 S:184 I:90
PLATFORM    : QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.6.6 08/22/2023 X86_HYPER_KVM
CPU VENDOR: GenuineIntel
MODEL NAME: Intel(R) Xeon(R) Platinum 8358 CPU @ 2.60GHz
CPU FAMILY: 6
CPUS      : 2
CPUS NUMA0: 0-1
MICROCODE : 0x1
CSTATES   : 9

====== MODULE mounts ======
DEVNAME                     TYPE        DIRNAME
-------                     ------      -------
none                        rootfs      /
sysfs                       sysfs       /sys
proc                        proc        /proc
devtmpfs                    devtmpfs    /dev
securityfs                  securityfs  /sys/kernel/security
tmpfs                       tmpfs       /dev/shm
devpts                      devpts      /dev/pts
tmpfs                       tmpfs       /run
tmpfs                       tmpfs       /sys/fs/cgroup
cgroup                      cgroup      /sys/fs/cgroup/systemd
pstore                      pstore      /sys/fs/pstore
efivarfs                    efivarfs    /sys/firmware/efi/efivars
bpf                         bpf         /sys/fs/bpf
cgroup                      cgroup      /sys/fs/cgroup/freezer
cgroup                      cgroup      /sys/fs/cgroup/rdma
cgroup                      cgroup      /sys/fs/cgroup/blkio
cgroup                      cgroup      /sys/fs/cgroup/hugetlb
cgroup                      cgroup      /sys/fs/cgroup/perf_event
cgroup                      cgroup      /sys/fs/cgroup/memory
cgroup                      cgroup      /sys/fs/cgroup/net_cls,net_prio
cgroup                      cgroup      /sys/fs/cgroup/misc
cgroup                      cgroup      /sys/fs/cgroup/pids
cgroup                      cgroup      /sys/fs/cgroup/cpuset
cgroup                      cgroup      /sys/fs/cgroup/cpu,cpuacct
cgroup                      cgroup      /sys/fs/cgroup/devices
none                        tracefs     /sys/kernel/tracing
configfs                    configfs    /sys/kernel/config
/dev/mapper/ocivolume-root  xfs         /
rpc_pipefs                  rpc_pipefs  /var/lib/nfs/rpc_pipefs
selinuxfs                   selinuxfs   /sys/fs/selinux
systemd-1                   autofs      /proc/sys/fs/binfmt_misc
mqueue                      mqueue      /dev/mqueue
hugetlbfs                   hugetlbfs   /dev/hugepages
debugfs                     debugfs     /sys/kernel/debug
/dev/sda2                   xfs         /boot
/dev/mapper/ocivolume-oled  xfs         /var/oled
/dev/sda1                   vfat        /boot/efi
fusectl                     fusectl     /sys/fs/fuse/connections
tmpfs                       tmpfs       /run/user/987
/dev/sdb1                   ext4        /mnt
tmpfs                       tmpfs       /run/user/1000
```

--------------------------------

### Install drgn-tools

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/drgn/installing_drgn_tools.html

Installs the drgn-tools package using dnf.

```bash
sudo dnf install -y drgn-tools
```

--------------------------------

### Start the libvirtd service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/kvm-user/kvm-ManageLibvirtdService.html

Initiates the libvirtd service using systemctl.

```bash
sudo systemctl start libvirtd
```

--------------------------------

### Sample Recommended Profile Output

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/tuned/tuned_command_reference.html

Example output showing the recommended profile.

```text
balanced
```

--------------------------------

### Start a user-based service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/systemd/CreatingasystemdUserBasedService.html

Manually start the user-level service.

```bash
systemctl --user start myservice.service
```

--------------------------------

### Install Leapp Utility

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/leapp/leapp-PreparingfortheUpgrade.html

Command to install the Leapp upgrade utility.

```bash
sudo yum install -y leapp-upgrade
```

--------------------------------

### Install nfs-utils

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/install/install-SettingUpanOracleLinuxNetworkInstallation.html

Installs the necessary utilities for managing NFS shares.

```bash
sudo dnf install nfs-utils -y
```

--------------------------------

### Import a QCOW2 disk image for a VM

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/kvm-user/kvm-CreatingaNewVirtualMachine.html

Creates a VM named ol8-guest-demo using an existing disk image. Specifying the os-variant is recommended to ensure optimal performance.

```bash
virt-install \
    --name ol8-guest-demo --memory 2048 --vcpus 2 \
    --os-variant ol8.0 --import \
    --disk /home/uniquename/backup/disk.qcow2
```

--------------------------------

### Verify gprofng-gui installation

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/gprofng/using_the_gprofng_gui.html

Check the installed version of the gprofng-gui component.

```bash
gprofng display gui --version
```

--------------------------------

### Install btrfs-progs

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/btrfs/btrfs-InstallingtheBtrfsUtilities.html

Installs the package containing Btrfs administration tools.

```bash
sudo dnf install -y btrfs-progs
```

--------------------------------

### Configure ptp4l Startup Options

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/network/network-AboutPTP.html

Define startup options in /etc/sysconfig/ptp4l for hardware or software time stamping.

```bash
OPTIONS="-f /etc/ptp4l.conf -i en1 -s"
```

```bash
OPTIONS="-f /etc/ptp4l.conf -i en1 -S -s"
```

--------------------------------

### Start a systemd timer

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/systemd/ConfiguringRealtimeTimerUnit.html

Command to start the timer for the current session.

```bash
sudo systemctl start update.timer
```

--------------------------------

### Configure dnsmasq

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/install/install-SettingUpanOracleLinuxNetworkInstallation.html

Example configuration for /etc/dnsmasq.conf, highlighting TFTP root and boot settings.

```text
interface=em1
dhcp-range=10.0.0.101,10.0.0.200,6h
dhcp-host=80:00:27:c6:a1:16,10.0.0.253,svr1,infinite
dhcp-boot=pxelinux/pxelinux.0
dhcp-match=set:efi-x86_64,option:client-arch,8
dhcp-boot=tag:efi-x86_64,shim.efi
enable-tftp
tftp-root=/var/lib/tftpboot
```

--------------------------------

### Example fstab entry

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/fsadmin/fsadmin-AbouttheFileSystemMountTable.html

A concrete example of a UUID-based fstab entry.

```text
UUID=79428c8f-d67a-49ec-ba20-8a86337f4447 /mnt/data  xfs  defaults  0 0
```

--------------------------------

### Install fcoe-utils Package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/stordev/stordev-WorkingWithLinuxIOStorage.html

Installs the fcoe-utils package for configuring FCoE storage.

```bash
sudo dnf install -y fcoe-utils
```

--------------------------------

### Enable and start the Watchdog service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/boot/boot-ConfigWatchdogServ.html

Use systemctl to configure the service to start automatically at boot and initiate it immediately.

```bash
sudo systemctl enable --now watchdog
```

--------------------------------

### Enable BRLTTY service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/accessibility/accessibility-UsingBraille.html

Enable the BRLTTY service to start on system boot.

```bash
sudo systemctl enable brltty
```

--------------------------------

### Install targetcli Package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/stordev/stordev-WorkingWithLinuxIOStorage.html

Installs the targetcli package required for managing LIO.

```bash
sudo dnf install -y targetcli
```

--------------------------------

### View virt-clone output example

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/kvm-user/kvm-CloningVirtualMachines.html

Example output showing the allocation of a new disk image and successful creation of a clone.

```text
virt-clone --original My_KVM --auto-clone
Allocating 'My_KVM-clone.qcow2'                            | 55.0 GB  00:02:37

Clone 'My_KVM-clone' created successfully.
```

--------------------------------

### Install a language pack

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/systemd/ConfigLocale.html

Install a specific language pack using dnf.

```bash
sudo dnf install langpacks-ja.noarch
```

--------------------------------

### Create a KVM Virtual Machine with virt-install

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/kvm-user/kvm-CreatingaNewVirtualMachine.html

Use this command to define and provision a new virtual machine with specified memory, CPU, storage, and OS parameters.

```bash
 virt-install \
 --name [unique-virtual-machine-name] \
 --memory [allocated-MiB-memory-size] \ 
 --vcpus [integer-vcpus-value-for-guest] \
 --location [installation-source-path] \
 --disk [type-and-size] \
 --os-variant [os-verison] \
 --network [default] \
 --graphics [none]
```

--------------------------------

### Initialize AIDE Database

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/security/security-UsingAdvancedIntrusionDetectionEnvironment.html

Creates the initial AIDE database representing the current system state.

```bash
sudo aide --init
```

--------------------------------

### Install AIDE

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/security/security-UsingAdvancedIntrusionDetectionEnvironment.html

Installs the AIDE package using the dnf package manager.

```bash
sudo dnf install -y aide
```

--------------------------------

### Install linuxptp Package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/network/network-AboutPTP.html

Install the necessary package to manage PTP services.

```bash
sudo dnf install linuxptp
```

--------------------------------

### Install the chrony package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/network/network-AboutthechronySuite.html

Use this command to install the chrony package on the system.

```bash
sudo dnf install chrony
```

--------------------------------

### Mounting methods by identifier

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/fsadmin/fsadmin-common_mount_syntax_and_options.html

Examples of mounting a device using its path, UUID, or label.

```bash
sudo mount /dev/sdb1 /mnt
```

```bash
sudo mount UUID="ad8113d7-b279-4da8-b6e4-cfba045f66ff" /mnt
```

```bash
sudo mount LABEL="Projects" /mnt
```

--------------------------------

### Specify Network Kickstart File Location

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/install/install-StartingtheKickstartInstallation.html

Use this format at the boot prompt to define the network server protocol and path for the Kickstart file.

```text
nfs:options:fqdn/path-to-file
```

--------------------------------

### Install gprofng-gui

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/gprofng/using_the_gprofng_gui.html

Use the dnf package manager to install the gprofng-gui package.

```bash
sudo dnf install -y gprofng-gui
```

--------------------------------

### Configure HugeTLB Page Pools via Kernel Boot Parameters

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/hugepages/hugepage-KernelBootParametersForHugeTLBPages.html

Examples of kernel command line options to reserve specific quantities of huge pages of varying sizes.

```text
hugepagesz=2M  hugepages=1500
```

```text
hugepagesz=1G hugepages=4 hugepagesz=2M hugepages=1500
```

--------------------------------

### Install the UEK kernel

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/btrfs/btrfs-InstallingtheBtrfsUtilities.html

Installs the Unbreakable Enterprise Kernel package on the system.

```bash
sudo dnf install -y kernel-uek
```

--------------------------------

### Install and Launch Firewall Configuration GUI

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/firewall/firewall-FirewallConfigurationTools.html

Commands to install the firewall-config package and launch the graphical user interface.

```bash
sudo dnf install firewall-config
```

```bash
sudo firewall-config &
```

--------------------------------

### Install kexec-tools package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/boot/monitoring-InstallingKdump.html

Installs the necessary tools required for Kdump functionality.

```bash
sudo dnf install kexec-tools
```

--------------------------------

### Example tuned.conf configuration

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/tuned/reviewing_tuned_profiles.html

A sample configuration file for the latency-performance profile demonstrating various system tuning sections.

```ini
[main]
summary=Optimize for deterministic performance at the cost of increased power consumption

[cpu]
force_latency=cstate.id_no_zero:1|3
governor=performance
energy_perf_bias=performance
min_perf_pct=100

[acpi]
platform_profile=performance

[sysctl]
# If a workload mostly uses anonymous memory and it hits this limit, the entire
# working set is buffered for I/O, and any more write buffering would require
# swapping, so it's time to throttle writes until I/O can catch up.  Workloads
# that mostly use file mappings may be able to use even higher values.
#
# The generator of dirty data starts writeback at this percentage (system default
# is 20%)
vm.dirty_ratio=10

# Start background writeback (via writeback threads) at this percentage (system
# default is 10%)
vm.dirty_background_ratio=3

# The swappiness parameter controls the tendency of the kernel to move
# processes out of physical memory and onto the swap disk.
# 0 tells the kernel to avoid swapping processes out of physical memory
# for as long as possible
# 100 tells the kernel to aggressively swap processes out of physical memory
# and move them to swap cache
vm.swappiness=10

[scheduler]
runtime=0
...
```

--------------------------------

### Install BRLTTY package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/accessibility/accessibility-UsingBraille.html

Install the necessary BRLTTY package using dnf.

```bash
sudo dnf install -y brltty
```

--------------------------------

### Creating Partitions Interactively

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/stordev/stordev-UsingDiskPartitions.html

Follow the interactive prompts to create new partitions, specifying type, number, and size.

```text
...
Command (m for help): `n`
Partition type
   p   primary (0 primary, 0 extended, 4 free)
   e   extended (container for logical partitions)
Select (default p): `p`
Partition number (1-4, default 1): `1`
First sector (2048-32767999, default 2048): `<Enter>`
Last sector, +sectors or +size{K,M,G,T,P} (2048-32767999, default 32767999): `+2G`

Created a new partition 1 of type 'Linux' and of size 2 GiB.

Command (m for help): `n`
Partition type
   p   primary (1 primary, 0 extended, 3 free)
   e   extended (container for logical partitions)
Select (default p): `p`
Partition number (2-4, default 2): `2`
First sector (4196352-32767999, default 4196352): `<Enter>`
Last sector, +sectors or +size{K,M,G,T,P} (4196352-32767999, default 32767999): `<Enter>`

Created a new partition 2 of type 'Linux' and of size 13.6 GiB.

Command (m for help): `p`
Disk /dev/sdb: 15.6 GiB, 16777216000 bytes, 32768000 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x460247f0

Device     Boot   Start      End  Sectors  Size Id Type
/dev/sdb1          2048  4196351  4194304    2G 83 Linux
/dev/sdb2       4196352 32767999 28571648 13.6G 83 Linux

Command (m for help): `w`
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.
```

--------------------------------

### Reload and start service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/systemd/SystemdMngCgroupsV2.html

Reload systemd configuration and start the specified service.

```bash
sudo systemctl daemon-reload
sudo systemctl enable myservice3 --now
```

--------------------------------

### Enable firewalld on boot

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/firewall/firewall-ControllingtheFirewallService.html

Configure the service to start automatically upon system boot.

```bash
sudo systemctl enable firewalld
```

--------------------------------

### Initialize the swap file

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/btrfs/btrfs-CreatingSwapFilesonaBtrfsFileSystem.html

Prepare the file for use as swap space.

```bash
sudo mkswap /swapfile
```

--------------------------------

### Start gprofng-gui

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/gprofng/using_the_gprofng_gui.html

Launch the gprofng graphical user interface.

```bash
gprofng display gui
```

--------------------------------

### Create disk partitions interactively

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/stordev/stordev-UsingDiskPartitions.html

Demonstrates the sequence of commands to create two partitions on a disk using the parted utility.

```text
GNU Parted 3.2
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) `print`
Model: ATA VBOX HARDDISK (scsi)
Disk /dev/sdb: 16.8GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags: 

Number  Start  End  Size  Type  File system  Flags

(parted) `mkpart`
Partition type?  primary/extended? `primary`
File system type?  [ext2]? `<Enter>`
Start? `1`
End? `2GB`
(parted) `print`
Model: ATA VBOX HARDDISK (scsi)
Disk /dev/sdb: 16.8GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags: 

Number  Start   End     Size    Type     File system  Flags
 1      1049kB  2000MB  1999MB  primary  ext2         lba

(parted) `mkpart`
Partition type?  primary/extended? `primary`
File system type?  [ext2]? `<Enter>`
Start? `2001`
End? `-0`
(parted) `print`
Model: ATA VBOX HARDDISK (scsi)
Disk /dev/sdb: 16.8GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags: 

Number  Start   End     Size    Type     File system  Flags
 1      1049kB  2000MB  1999MB  primary  ext2         lba
 2      2001MB  16.8GB  14.8GB  primary  ext2         lba

(parted) `quit`
```

--------------------------------

### Install Device Mapper Multipath

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/stordev/stordev-UsingMultipathingforEfficientStorage.html

Install the required package to enable multipathing functionality.

```bash
sudo dnf install device-mapper-multipath
```

--------------------------------

### Enable a service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/systemd/EnablingandDisablingServices.html

Enables a service to start at boot by creating a symbolic link.

```bash
sudo systemctl enable httpd
```

--------------------------------

### Install the sos package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/sos/about_the_sos_command.html

Use this command to install the necessary package for system diagnostics.

```bash
sudo dnf install sos
```

--------------------------------

### Starting fdisk for a Device

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/stordev/stordev-UsingDiskPartitions.html

Initiate the fdisk utility for a specific storage device to begin partition management.

```bash
sudo fdisk /dev/sdb
```

--------------------------------

### Install PHP 8.2 Module

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/relnotes8.10/ol8-features-DynamicProgramming.html

Command to install the PHP 8.2 module stream.

```bash
sudo dnf module install php:8.2
```

--------------------------------

### Install and Enable Watchdog Service

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/availability/availability-FencingConfigurationExamples.html

Install the watchdog service and deploy the fence_scsi_check script to enable storage-level fencing monitoring.

```bash
sudo dnf install watchdog
sudo cp /usr/share/cluster/fence_scsi_check /etc/watchdog.d/
sudo systemctl enable --now watchdog
```

--------------------------------

### Install dnsmasq

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/install/install-SettingUpanOracleLinuxNetworkInstallation.html

Installs the dnsmasq package to provide DHCP, DNS, and TFTP services.

```bash
sudo dnf install dnsmasq -y
```

--------------------------------

### Create a user-based service unit file

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/systemd/CreatingasystemdUserBasedService.html

Initialize the service unit file within the user's configuration directory.

```bash
touch $HOME/.config/systemd/user/myservice.service
```

--------------------------------

### Creating and Formatting a File System Image

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/fsadmin/fsadmin-common_mount_syntax_and_options.html

Commands to create an empty file, format it with a file system, and mount it.

```bash
sudo dd if=/dev/zero of=/fsfile bs=1M count=4096
```

```bash
sudo fallocate -l 4G /fsfile
```

```bash
sudo mkfs.ext4 -F /fsfile
```

```bash
sudo mount -o loop /fsfile /mnt
```

--------------------------------

### Install autofs package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/fsadmin/fsadmin-managing_on_demand_mounts_using_autofs.html

Installs the autofs package required for on-demand mounting functionality.

```bash
sudo dnf install autofs
```

--------------------------------

### Example udev rules syntax

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/udev/udev-AboutudevRules.html

Illustrates standard udev rule syntax for managing device attributes, permissions, and symlinks.

```udev
# do not edit this file, it will be overwritten on update

SUBSYSTEM=="block", SYMLINK{unique}+="block/%M:%m"
SUBSYSTEM!="block", SYMLINK{unique}+="char/%M:%m"

KERNEL=="pty[pqrstuvwxyzabcdef][0123456789abcdef]", GROUP="tty", MODE="0660"
KERNEL=="tty[pqrstuvwxyzabcdef][0123456789abcdef]", GROUP="tty", MODE="0660"
...
# mem
KERNEL=="null|zero|full|random|urandom", MODE="0666"
KERNEL=="mem|kmem|port|nvram",  GROUP="kmem", MODE="0640"
...
# block
SUBSYSTEM=="block", GROUP="disk"
...
# network
KERNEL=="tun",                  MODE="0666"
KERNEL=="rfkill",               MODE="0644"

# CPU
KERNEL=="cpu[0-9]*",            MODE="0444"
...
# do not delete static device nodes
ACTION=="remove", NAME=="", TEST=="/lib/udev/devices/%k", \
    OPTIONS+="ignore_remove"
ACTION=="remove", NAME=="?*", TEST=="/lib/udev/devices/$name", \
    OPTIONS+="ignore_remove"
```

--------------------------------

### Install fapolicyd package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/fapolicyd/fapolicyd-Install.html

Installs the fapolicyd package using the dnf package manager.

```bash
sudo dnf install fapolicyd
```

--------------------------------

### Install the quota package

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/ext/ext-EnablingDiskQuotasonFileSystems.html

Installs the necessary utilities for managing disk quotas on the system.

```bash
sudo dnf install -y quota
```

--------------------------------

### Configure and Verify Module Loading

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/boot/boot-SpecifyingModulesToBeLoadedatBootTime.html

Commands to create a configuration file for a module and verify its contents.

```bash
echo bnxt_en | sudo tee /etc/modules-load.d/bnxt_en.conf
```

```bash
cat /etc/modules-load.d/bnxt_en.conf
```

--------------------------------

### Install drgn for Python 3.12

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/drgn/using_the_drgn_library_with_python.html

Install the drgn package specifically for Python 3.12.

```bourne
sudo dnf install python3.12-drgn
```

--------------------------------

### Launch nm-connection-editor

Source: https://docs.oracle.com/en/operating-systems/oracle-linux/8/network/network-CreateKeyfileConnectionProfile-nm-connection-editor.html

Starts the graphical network connection editor application with root privileges.

```bash
sudo nm-connection-editor
```
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