Things has to be done after installing RHEL 9

 -Cockpit Enablement
    systemctl enable --now cockpit.socket
-RedHat 9.x
    subscription check: https://access.redhat.com/management
    subscription-manager register
    username/password
    subscription-manager status  
    subscription-manager list --consumed
    subscription-manager repos --list
    dnf update
-Set Hostname
    hostnamectl set-hostname porulagam.redhat
-Unregister and reregister
    sudo subscription-manager remove --all
    sudo subscription-manager unregister
    sudo subscription-manager clean
    sudo subscription-manager register
    sudo subscription-manager refresh
    sudo subscription-manager attach --auto
-Xtreme Download Manager
    Download from internet and run the install.sh script
-Gnome-tweaks
    dnf install gnome-tweaks
-Ansible
    dnf install ansible-core
-Virtualbox
    Download the rpm from https://www.virtualbox.org/wiki/Linux_Downloads
    dnf install *.rpm
    usermod -a -G vboxusers $USER
    groups $USER
    #systemctl status vboxdrv
-Kernel related modules for virtualbox    
    dnf install make time perl gcc dkms kernel-devel kernel-headers
    /sbin/vboxconfig
-Libre Office Latest
    Download the latest office from https://www.libreoffice.org/download/download/
    Extract the compressed file 
    dnf install *.rpm
-Libre Office uninstallaion
    dnf remove libreoffice*
    dnf clean all
-VLC
    sudo dnf install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
    sudo dnf upgrade
    sudo rpm -ivh https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
    sudo subscription-manager repos --enable "rhel-*-optional-rpms" --enable "rhel-*-extras-rpms"
    sudo yum update
    sudo yum install snapd
    sudo systemctl enable --now snapd.socket
    sudo ln -s /var/lib/snapd/snap /snap
    sudo snap install vlc
-Remove Totem player
    dnf remove totem
-Grub update and scan other installed OSes
    grub2-mkconfig -o /boot/grub2/grub.cfg
-To repair the corrupted xfs partition 
    Run the below command in the rescue mode
    xfs_repair -v -L /dev/dm-0
-VS Codium Installation
    Download the latest rpm package from this link
    https://github.com/VSCodium/vscodium/releases
    yum localinstall codium-1.84.2.23319-el7.x86_64.rpm
-To disable selinux fully
    grubby --update-kernel ALL --args selinux=0 
-To back to enable
    grubby --update-kernel ALL --remove-args selinux