Prepare a Red Hat-based virtual machine for Azure

1. In Hyper-V Manager, select the VM.

2. Select Connect to open a console window for the VM.

3. Create or edit the /etc/sysconfig/network file, and add the following text:

   NETWORKING=yes
   HOSTNAME=localhost.localdomain
   

4. Create or edit the /etc/sysconfig/network-scripts/ifcfg-eth0 file, and add the following text:

   DEVICE=eth0
   ONBOOT=yes
   BOOTPROTO=dhcp
   TYPE=Ethernet
   USERCTL=no
   PEERDNS=yes
   IPV6INIT=no
   PERSISTENT_DHCLIENT=yes
   NM_CONTROLLED=yes
   

   Note

   When you use Accelerated Networking, the synthetic interface that's created must be configured to be unmanaged by using a udev rule. This action prevents NetworkManager from assigning the same IP to it as the primary interface.
   

   To apply it:
   

   sudo tee <<EOF /etc/udev/rules.d/68-azure-sriov-nm-unmanaged.rules > /dev/null
   # Accelerated Networking on Azure exposes a new SRIOV interface to the VM.
   # This interface is transparently bonded to the synthetic interface,
   # so NetworkManager should just ignore any SRIOV interfaces.
   SUBSYSTEM=="net", DRIVERS=="hv_pci", ACTION!="remove", ENV{NM_UNMANAGED}="1"
   EOF
   

5. Ensure that the network service starts at boot time:

   sudo systemctl enable network
   

6. Register your Red Hat subscription to enable the installation of packages from the RHEL repository:

   sudo subscription-manager register --auto-attach --username=XXX --password=XXX
   

7. Modify the kernel boot line in your grub configuration to include more kernel parameters for Azure. To do this modification, open /etc/default/grub in a text editor and edit the GRUB_CMDLINE_LINUX parameter. For example:

   GRUB_CMDLINE_LINUX="console=tty1 console=ttyS0,115200n8 earlyprintk=ttyS0 net.ifnames=0"
   GRUB_TERMINAL_OUTPUT="serial console"
   GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1"
   ENABLE_BLSCFG=true
   

   Note

   If ENABLE_BLSCFG=false is present in /etc/default/grub instead of ENABLE_BLSCFG=true, tools such as grubedit or gubby, which rely on the Boot Loader Specification (BLS) for managing boot entries and configurations, might not function correctly in RHEL 8 and 9. If ENABLE_BLSCFG isn't present, the default behavior is false.

   This modification also ensures that all console messages are sent to the first serial port and enables interaction with the serial console, which can assist Azure support with debugging issues. This configuration also turns off the new naming conventions for network interface cards (NICs).

   rhgb quiet crashkernel=auto
   

   Graphical and quiet boots aren't useful in a cloud environment where you want all the logs to be sent to the serial port. You can leave the crashkernel option configured if you want. This parameter reduces the amount of available memory in the VM by 128 MB or more, which might be a problem for smaller VM sizes.

8. After you're finished editing /etc/default/grub, run the following command to rebuild the grub configuration:

   sudo grub2-mkconfig -o /boot/grub2/grub.cfg
   

   Note

   If you're uploading a UEFI-enabled VM, the command to update grub is grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg.

9. Ensure that the SSH server is installed and configured to start at boot time, which is usually the default. Modify /etc/ssh/sshd_config to include the following line:

   ClientAliveInterval 180
   

10. The WALinuxAgent package, WALinuxAgent-<version>, has been pushed to the Red Hat extras repository. Enable the extras repository:

    sudo subscription-manager repos --enable=rhel-7-server-extras-rpms
    

11. Install the Azure Linux agent, cloud-init, and other necessary utilities:

    sudo yum install -y WALinuxAgent cloud-init cloud-utils-growpart gdisk hyperv-daemons
    sudo systemctl enable waagent.service
    sudo systemctl enable cloud-init.service
    

12. Configure cloud-init to handle the provisioning:

    1. Configure waagent for cloud-init:

       sudo sed -i 's/Provisioning.Agent=auto/Provisioning.Agent=auto/g' /etc/waagent.conf
       sudo sed -i 's/ResourceDisk.Format=y/ResourceDisk.Format=n/g' /etc/waagent.conf
       sudo sed -i 's/ResourceDisk.EnableSwap=y/ResourceDisk.EnableSwap=n/g' /etc/waagent.conf
       

       Note

       If you're migrating a specific VM and don't want to create a generalized image, set Provisioning.Agent=disabled on the /etc/waagent.conf configuration.

    2. Configure mounts:

       sudo echo "Adding mounts and disk_setup to init stage"
       sudo sed -i '/ - mounts/d' /etc/cloud/cloud.cfg
       sudo sed -i '/ - disk_setup/d' /etc/cloud/cloud.cfg
       sudo sed -i '/cloud_init_modules/a\\ - mounts' /etc/cloud/cloud.cfg
       sudo sed -i '/cloud_init_modules/a\\ - disk_setup' /etc/cloud/cloud.cfg
       

    3. Configure the Azure data source:

       sudo echo "Allow only Azure datasource, disable fetching network setting via IMDS"
       sudo tee /etc/cloud/cloud.cfg.d/91-azure_datasource.cfg <<EOF
       datasource_list: [ Azure ]
       datasource:
           Azure:
               apply_network_config: False
       EOF
       

    4. If configured, remove the existing swap file:

       if [[ -f /mnt/resource/swapfile ]]; then
       echo "Removing swapfile" #RHEL uses a swapfile by default
       swapoff /mnt/resource/swapfile
       rm /mnt/resource/swapfile -f
       fi
       

    5. Configure cloud-init logging:

       sudo echo "Add console log file"
       sudo tee <<EOF /etc/cloud/cloud.cfg.d/05_logging.cfg > /dev/null
       
       # This tells cloud-init to redirect its stdout and stderr to
       # 'tee -a /var/log/cloud-init-output.log' so the user can see output
       # there without needing to look on the console.
       output: {all: '| tee -a /var/log/cloud-init-output.log'}
       EOF
       

13. Swap configuration:

    • Don't create swap space on the operating system disk.

      Previously, the Azure Linux agent was used to automatically configure swap space by using the local resource disk that's attached to the VM after the VM is provisioned on Azure. This action is now handled by cloud-init. You must not use the Linux agent to format the resource disk to create the swap file. Modify the following parameters in /etc/waagent.conf appropriately:

      ResourceDisk.Format=n
      ResourceDisk.EnableSwap=n
      

    • If you want to mount, format, and create the swap, you can either:

      • Pass this code in as a cloud-init configuration every time you create a VM through custom data. We recommend this method.

      • Use a cloud-init directive baked into the image that does this step every time the VM is created.

        sudo echo 'DefaultEnvironment="CLOUD_CFG=/etc/cloud/cloud.cfg.d/00-azure-swap.cfg"' >> /etc/systemd/system.conf
        sudo tee /etc/cloud/cloud.cfg.d/00-azure-swap.cfg <<EOF    
        #cloud-config
        # Generated by Azure cloud image build
        disk_setup:
          ephemeral0:
            table_type: mbr
            layout: [66, [33, 82]]
            overwrite: True
        fs_setup:
          - device: ephemeral0.1
            filesystem: ext4
          - device: ephemeral0.2
            filesystem: swap
        mounts:
          - ["ephemeral0.1", "/mnt/resource"]
          - ["ephemeral0.2", "none", "swap", "sw,nofail,x-systemd.requires=cloud-init.service,x-systemd.device-timeout=2", "0", "0"]
        EOF
        

14. Configure cloud-init telemetry to assist with troubleshooting for provisioning issues:

    sudo tee -a /etc/cloud/cloud.cfg.d/10-azure-kvp.cfg <<EOF
    # This config enables cloud-init to report provisioning telemetry to aid with troubleshooting
    Reporting:
      logging:
        type: log
      telemetry:
        type: hyperv
    EOF
    

15. If you want to unregister the subscription, run the following command:

    
    sudo subscription-manager unregister
    

16. Deprovision the VM and prepare it for provisioning on Azure:

    Caution

    If you're migrating a specific VM and don't want to create a generalized image, skip the deprovision step. Running the command waagent -force -deprovision+user renders the source machine unusable. This step is intended only to create a generalized image.

    sudo rm -f /var/log/waagent.log
    sudo cloud-init clean --logs --seed
    sudo waagent -force -deprovision+user
    sudo rm -f ~/.bash_history
    sudo export HISTSIZE=0
    

17. Select Action > Shut Down in Hyper-V Manager. Your Linux VHD is now ready to be uploaded to Azure.

1. In Hyper-V Manager, select the VM.

2. Select Connect to open a console window for the VM.

3. Ensure that the Network Manager service starts at boot time:

   sudo systemctl enable NetworkManager.service
   

4. Configure the network interface to automatically start at boot and use the Dynamic Host Configuration Protocol:

   sudo nmcli con mod eth0 connection.autoconnect yes ipv4.method auto
   

   Note

   When you use Accelerated Networking, the synthetic interface that's created must be configured to be unmanaged by using a udev rule. This action prevents NetworkManager from assigning the same IP to it as the primary interface.
   

   To apply it:
   

   sudo tee <<EOF /etc/udev/rules.d/68-azure-sriov-nm-unmanaged.rules > /dev/null
   # Accelerated Networking on Azure exposes a new SRIOV interface to the VM.
   # This interface is transparently bonded to the synthetic interface,
   # so NetworkManager should just ignore any SRIOV interfaces.
   SUBSYSTEM=="net", DRIVERS=="hv_pci", ACTION!="remove", ENV{NM_UNMANAGED}="1"
   EOF
   

5. Register your Red Hat subscription to enable the installation of packages from the RHEL repository:

   sudo subscription-manager register --auto-attach --username=XXX --password=XXX
   

6. Modify the kernel boot line in your grub configuration to include more kernel parameters for Azure and enable the serial console.

7. Remove current GRUB parameters:

   sudo grub2-editenv - unset kernelopts
   

8. Edit /etc/default/grub in a text editor, and add the following parameters:

   GRUB_CMDLINE_LINUX="console=tty1 console=ttyS0,115200n8 earlyprintk=ttyS0,115200 earlyprintk=ttyS0 net.ifnames=0"
   GRUB_TERMINAL_OUTPUT="serial console"
   GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1"
   

   This modification also ensures that all console messages are sent to the first serial port and enable interaction with the serial console, which can assist Azure support with debugging issues. This configuration also turns off the new naming conventions for NICs.

9. We recommend that you also remove the following parameters:

   rhgb quiet crashkernel=auto
   

   Graphical and quiet boots aren't useful in a cloud environment where you want all the logs to be sent to the serial port. You can leave the crashkernel option configured if you want. This parameter reduces the amount of available memory in the VM by 128 MB or more, which might be a problem for smaller VM sizes.

10. After you're finished editing /etc/default/grub, run the following command to rebuild the grub configuration:

    sudo grub2-mkconfig -o /boot/grub2/grub.cfg
    

    For a UEFI-enabled VM, run the following command:

    sudo grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg
    

11. Ensure that the SSH server is installed and configured to start at boot time, which is usually the default. Modify /etc/ssh/sshd_config to include the following line:

    ClientAliveInterval 180
    

12. Install the Azure Linux agent, cloud-init, and other necessary utilities:

    sudo yum install -y WALinuxAgent cloud-init cloud-utils-growpart gdisk hyperv-daemons
    sudo systemctl enable waagent.service
    sudo systemctl enable cloud-init.service
    

13. Configure cloud-init to handle the provisioning:

    1. Configure waagent for cloud-init:

       sudo sed -i 's/Provisioning.Agent=auto/Provisioning.Agent=cloud-init/g' /etc/waagent.conf 
       sudo sed -i 's/ResourceDisk.Format=y/ResourceDisk.Format=n/g' /etc/waagent.conf
       sudo sed -i 's/ResourceDisk.EnableSwap=y/ResourceDisk.EnableSwap=n/g' /etc/waagent.conf
       

       Note

       If you're migrating a specific VM and don't want to create a generalized image, set Provisioning.Agent=disabled on the /etc/waagent.conf configuration.

    2. Configure mounts:

       sudo echo "Adding mounts and disk_setup to init stage"
       sudo sed -i '/ - mounts/d' /etc/cloud/cloud.cfg
       sudo sed -i '/ - disk_setup/d' /etc/cloud/cloud.cfg
       sudo sed -i '/cloud_init_modules/a\\ - mounts' /etc/cloud/cloud.cfg
       sudo sed -i '/cloud_init_modules/a\\ - disk_setup' /etc/cloud/cloud.cfg
       

    3. Configure the Azure data source:

       sudo echo "Allow only Azure datasource, disable fetching network setting via IMDS"
       sudo tee /etc/cloud/cloud.cfg.d/91-azure_datasource.cfg <<EOF
       datasource_list: [ Azure ]
       datasource:
           Azure:
               apply_network_config: False
       EOF
       

    4. If configured, remove the existing swap file:

       if [[ -f /mnt/resource/swapfile ]]; then
       echo "Removing swapfile" #RHEL uses a swapfile by defaul
       swapoff /mnt/resource/swapfile
       rm /mnt/resource/swapfile -f
       fi
       

    5. Configure cloud-init logging:

       sudo echo "Add console log file"
       sudo tee <<EOF /etc/cloud/cloud.cfg.d/05_logging.cfg > /dev/null 
       
       # This tells cloud-init to redirect its stdout and stderr to
       # 'tee -a /var/log/cloud-init-output.log' so the user can see output
       # there without needing to look on the console.
       output: {all: '| tee -a /var/log/cloud-init-output.log'}
       EOF
       

14. Swap configuration:

    • Don't create swap space on the operating system disk.

      Previously, the Azure Linux agent was used to automatically configure swap space by using the local resource disk that's attached to the VM after the VM is provisioned on Azure. This action is now handled by cloud-init. You must not use the Linux agent to format the resource disk create the swap file. Modify the following parameters in /etc/waagent.conf appropriately:

      ResourceDisk.Format=n
      ResourceDisk.EnableSwap=n
      

      • Pass this code in as a cloud-init configuration every time you create a VM through custom data. We recommend this method.

      • Use a cloud-init directive baked into the image that does this step every time the VM is created.

        sudo echo 'DefaultEnvironment="CLOUD_CFG=/etc/cloud/cloud.cfg.d/00-azure-swap.cfg"' >> /etc/systemd/system.conf
        sudo tee  /etc/cloud/cloud.cfg.d/00-azure-swap.cfg <<EOF
        #cloud-config
        # Generated by Azure cloud image build
        disk_setup:
          ephemeral0:
            table_type: mbr
            layout: [66, [33, 82]]
            overwrite: True
        fs_setup:
          - device: ephemeral0.1
            filesystem: ext4
          - device: ephemeral0.2
            filesystem: swap
        mounts:
          - ["ephemeral0.1", "/mnt/resource"]
          - ["ephemeral0.2", "none", "swap", "sw,nofail,x-systemd.device-timeout=2,x-systemd.requires=cloud-init.service", "0", "0"]
        EOF
        

15. Configure cloud-init telemetry to assist with troubleshooting for provisioning issues:

    sudo tee -a /etc/cloud/cloud.cfg.d/10-azure-kvp.cfg <<EOF
    # This config enables cloud-init to report provisioning telemetry to aid with troubleshooting
    Reporting:
      logging:
        type: log
      telemetry:
        type: hyperv
    EOF
    

16. If you want to unregister the subscription, run the following command:

    sudo subscription-manager unregister
    

17. Run the following commands to deprovision the VM and prepare it for provisioning on Azure:

    sudo cloud-init  clean --logs --seed
    sudo waagent -force -deprovision+user
    sudo rm -f ~/.bash_history
    sudo sudo rm -f /var/log/waagent.log
    sudo export HISTSIZE=0
    

    Caution

    If you're migrating a specific VM and don't want to create a generalized image, skip the deprovision step. Running the command waagent -force -deprovision+user renders the source machine unusable. This step is intended only to create a generalized image.

18. Select Action > Shut Down in Hyper-V Manager. Your Linux VHD is now ready to be uploaded to Azure.

This section shows you how to use KVM to prepare RHEL 7 to upload to Azure.

1. Download the RHEL 7 KVM image of from the Red Hat website.

2. Set a root password.

   Generate an encrypted password, and copy the output of the command:

   sudo openssl passwd -1 changeme
   

   Set a root password with guestfish:

   sudo guestfish --rw -a <image-name>
   > <fs> run
   > <fs> list-filesystems
   > <fs> mount /dev/sda1 /
   > <fs> vi /etc/shadow
   > <fs> exit
   

   Change the second field for the root user from !! to the encrypted password.

3. Create a VM in KVM from the qcow2 image. Set the disk type to qcow2, and set the virtual network interface device model to virtio. Then, start the VM and sign in as root.

4. Create or edit the /etc/sysconfig/network file, and add the following text:

   NETWORKING=yes
   HOSTNAME=localhost.localdomain
   

5. Create or edit the /etc/sysconfig/network-scripts/ifcfg-eth0 file, and add the following text:

   DEVICE=eth0
   ONBOOT=yes
   BOOTPROTO=dhcp
   TYPE=Ethernet
   USERCTL=no
   PEERDNS=yes
   IPV6INIT=no
   PERSISTENT_DHCLIENT=yes
   NM_CONTROLLED=yes
   

   Note

   When you use Accelerated Networking, the synthetic interface that's created must be configured to be unmanaged by using a udev rule. This action prevents NetworkManager from assigning the same IP to it as the primary interface.
   

   To apply it:
   

   sudo tee <<EOF /etc/udev/rules.d/68-azure-sriov-nm-unmanaged.rules > /dev/null
   # Accelerated Networking on Azure exposes a new SRIOV interface to the VM.
   # This interface is transparently bonded to the synthetic interface,
   # so NetworkManager should just ignore any SRIOV interfaces.
   SUBSYSTEM=="net", DRIVERS=="hv_pci", ACTION!="remove", ENV{NM_UNMANAGED}="1"
   EOF
   

6. Ensure that the network service starts at boot time:

   sudo systemctl enable network
   

7. Register your Red Hat subscription to enable installation of packages from the RHEL 7 repository:

   sudo subscription-manager register --auto-attach --username=XXX --password=XXX
   

8. Modify the kernel boot line in your grub configuration to include more kernel parameters for Azure. To do this configuration, open /etc/default/grub in a text editor and edit the GRUB_CMDLINE_LINUX parameter. For example:

   GRUB_CMDLINE_LINUX="console=ttyS0 earlyprintk=ttyS0 net.ifnames=0"
   

   This command also ensures that all console messages are sent to the first serial port, which can assist Azure support with debugging issues. The command also turns off the new naming conventions for NICs. We also recommend that you remove the following parameters:

   rhgb quiet crashkernel=auto
   

   Graphical and quiet boots aren't useful in a cloud environment where you want all the logs to be sent to the serial port. You can leave the crashkernel option configured if you want. This parameter reduces the amount of available memory in the VM by 128 MB or more, which might be a problem for smaller VM sizes.

9. After you're finished editing /etc/default/grub, run the following command to rebuild the grub configuration:

   sudo grub2-mkconfig -o /boot/grub2/grub.cfg
   

10. Add Hyper-V modules into initramfs.

    Edit /etc/dracut.conf and add content:

    add_drivers+=" hv_vmbus hv_netvsc hv_storvsc "
    

    Rebuild initramfs:

    sudo dracut -f -v
    

11. Uninstall cloud-init:

    sudo yum remove cloud-init
    

12. Ensure that the SSH server is installed and configured to start at boot time:

    sudo systemctl enable sshd
    

    Modify /etc/ssh/sshd_config to include the following lines:

    PasswordAuthentication yes
    ClientAliveInterval 180
    

13. The WALinuxAgent package, WALinuxAgent-<version>, has been pushed to the Red Hat extras repository. Enable the extras repository:

    sudo subscription-manager repos --enable=rhel-7-server-extras-rpms
    

14. Install the Azure Linux agent:

    sudo yum install WALinuxAgent
    

    Enable the waagent service:

    sudo systemctl enable waagent.service
    

15. Install cloud-init.

    Follow the steps in "Prepare a RHEL 7 VM from Hyper-V Manager," step 12, "Install cloud-init to handle the provisioning."

16. Swap configuration:

    • Don't create swap space on the operating system disk.
    • Follow the steps in "Prepare a VM from Hyper-V Manager," step 13, "Swap configuration."

17. Unregister the subscription (if necessary):

    sudo subscription-manager unregister
    

18. Deprovision by following the steps in "Prepare a VM from Hyper-V Manager," step 15, "Deprovision."

19. Shut down the VM in KVM.

20. Convert the qcow2 image to the VHD format.

    Note

    There's a known bug in qemu-img versions >=2.2.1 that results in an improperly formatted VHD. The issue has been fixed in QEMU 2.6. We recommend that you use either qemu-img 2.2.0 or lower, or update to 2.6 or higher. For more information, see this website.

    First convert the image to raw format:

    sudo qemu-img convert -f qcow2 -O raw rhel-7.4.qcow2 rhel-7.4.raw
    

    Make sure that the size of the raw image is aligned with 1 MB. Otherwise, round up the size to align with 1 MB:

    MB=$((1024*1024))
    size=$(qemu-img info -f raw --output json "rhel-7.4.raw" | \
    gawk 'match($0, /"virtual-size": ([0-9]+),/, val) {print val[1]}')
    rounded_size=$((($size/$MB + 1)*$MB))
    sudo qemu-img resize rhel-7.4.raw $rounded_size
    

    Convert the raw disk to a fixed-size VHD:

    sudo qemu-img convert -f raw -o subformat=fixed -O vpc rhel-7.4.raw rhel-7.4.vhd
    

    Or, with qemu version 1.6+, include the force_size option:

    sudo qemu-img convert -f raw -o subformat=fixed,force_size -O vpc rhel-7.4.raw rhel-7.4.vhd
    

1. Ensure that the Network Manager service starts at boot time:

   sudo systemctl enable NetworkManager.service
   

2. Configure the network interface to automatically start at boot and use the Dynamic Host Configuration Protocol:

   sudo nmcli con mod eth0 connection.autoconnect yes ipv4.method auto
   

   Note

   When you use Accelerated Networking, the synthetic interface that's created must be configured to be unmanaged by using a udev rule. This action prevents NetworkManager from assigning the same IP to it as the primary interface.
   

   To apply it:
   

   sudo tee <<EOF /etc/udev/rules.d/68-azure-sriov-nm-unmanaged.rules >/dev/null
   # Accelerated Networking on Azure exposes a new SRIOV interface to the VM.
   # This interface is transparently bonded to the synthetic interface,
   # so NetworkManager should just ignore any SRIOV interfaces.
   SUBSYSTEM=="net", DRIVERS=="hv_pci", ACTION!="remove", ENV{NM_UNMANAGED}="1"
   EOF
   

3. Register your Red Hat subscription to enable the installation of packages from the RHEL repository:

   sudo subscription-manager register --auto-attach --username=XXX --password=XXX
   

4. Modify the kernel boot line in your grub configuration to include more kernel parameters for Azure and enable the serial console.

5. Remove current GRUB parameters:

   sudo grub2-editenv - unset kernelopts
   

6. Edit /etc/default/grub in a text editor, and add the following parameters:

   GRUB_CMDLINE_LINUX="console=tty1 console=ttyS0,115200n8 earlyprintk=ttyS0,115200 earlyprintk=ttyS0 net.ifnames=0"
   GRUB_TERMINAL_OUTPUT="serial console"
   GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1"
   

   This modification also ensures that all console messages are sent to the first serial port and enable interaction with the serial console, which can assist Azure support with debugging issues. This configuration also turns off the new naming conventions for NICs.

7. We recommend that you also remove the following parameters:

   rhgb quiet crashkernel=auto
   

   Graphical and quiet boots aren't useful in a cloud environment where you want all the logs to be sent to the serial port. You can leave the crashkernel option configured if you want. This parameter reduces the amount of available memory in the VM by 128 MB or more, which might be a problem for smaller VM sizes.

8. After you're finished editing /etc/default/grub, run the following command to rebuild the grub configuration:

   sudo grub2-mkconfig -o /boot/grub2/grub.cfg
   

9. Add Hyper-V modules into initramfs.

   Create /etc/dracut.conf.d/azure.conf and add content:

   add_drivers+=" hv_vmbus hv_netvsc hv_storvsc "
   

   Rebuild initramfs:

   sudo dracut -f -v
   

10. Ensure that the SSH server is installed and configured to start at boot time, which is usually the default. Modify /etc/ssh/sshd_config to include the following line:

    ClientAliveInterval 180
    

11. Install the Azure Linux agent, cloud-init, and other necessary utilities:

    sudo yum install -y WALinuxAgent cloud-init cloud-utils-growpart gdisk hyperv-daemons
    sudo systemctl enable waagent.service
    sudo systemctl enable cloud-init.service
    

12. Configure cloud-init to handle the provisioning:

    1. Configure waagent for cloud-init:

       sudo sed -i 's/Provisioning.Agent=auto/Provisioning.Agent=cloud-init/g' /etc/waagent.conf
       sudo sed -i 's/ResourceDisk.Format=y/ResourceDisk.Format=n/g' /etc/waagent.conf
       sudo sed -i 's/ResourceDisk.EnableSwap=y/ResourceDisk.EnableSwap=n/g' /etc/waagent.conf
       

       Note

       If you're migrating a specific VM and don't want to create a generalized image, set Provisioning.Agent=disabled on the /etc/waagent.conf configuration.

    2. Configure mounts:

       sudo echo "Adding mounts and disk_setup to init stage"
       sudo sed -i '/ - mounts/d' /etc/cloud/cloud.cfg
       sudo sed -i '/ - disk_setup/d' /etc/cloud/cloud.cfg
       sudo sed -i '/cloud_init_modules/a\\  - mounts' /etc/cloud/cloud.cfg
       sudo sed -i '/cloud_init_modules/a\\  - disk_setup' /etc/cloud/cloud.cfg
       

       Note

       The items for each section in the /etc/cloud/cloud.cfg file must use the same level of indentation

       Example of an incorrect setting:

       cloud_init_modules:
        - disk_setup
        - mounts 
         - migrators
       

       Example of a correct setting:

       cloud_init_modules:
         - disk_setup
         - mounts 
         - migrators
       

    3. Configure the Azure data source:

       sudo echo "Allow only Azure datasource, disable fetching network setting via IMDS"
       sudo tee /etc/cloud/cloud.cfg.d/91-azure_datasource.cfg <<EOF
       datasource_list: [ Azure ]
       datasource:
           Azure:
               apply_network_config: False
       EOF
       

    4. If configured, remove the existing swap file:

       if [[ -f /mnt/resource/swapfile ]]; then
       echo "Removing swapfile" #RHEL uses a swapfile by default
       swapoff /mnt/resource/swapfile
       rm /mnt/resource/swapfile -f
       fi
       

    5. Configure cloud-init logging:

       sudo echo "Add console log file"
       sudo tee <<EOF /etc/cloud/cloud.cfg.d/05_logging.cfg >/dev/null 
       
       # This tells cloud-init to redirect its stdout and stderr to
       # 'tee -a /var/log/cloud-init-output.log' so the user can see output
       # there without needing to look on the console.
       output: {all: '| tee -a /var/log/cloud-init-output.log'}
       EOF
       

13. Swap configuration:

    • Don't create swap space on the operating system disk.

      Previously, the Azure Linux agent was used to automatically configure swap space by using the local resource disk that's attached to the VM after the VM is provisioned on Azure. This action is now handled by cloud-init. You must not use the Linux agent to format the resource disk create the swap file. Modify the following parameters in /etc/waagent.conf appropriately:

      ResourceDisk.Format=n
      ResourceDisk.EnableSwap=n
      

      • Pass this code in as a cloud-init configuration every time you create a VM through custom data. We recommend this method.

      • Use a cloud-init directive baked into the image that does this step every time the VM is created.

        sudo echo 'DefaultEnvironment="CLOUD_CFG=/etc/cloud/cloud.cfg.d/00-azure-swap.cfg"' >> /etc/systemd/system.conf
        sudo tee /etc/cloud/cloud.cfg.d/00-azure-swap.cfg <<EOF
        #cloud-config
        # Generated by Azure cloud image build
        disk_setup:
          ephemeral0:
            table_type: mbr
            layout: [66, [33, 82]]
            overwrite: True
        fs_setup:
          - device: ephemeral0.1
            filesystem: ext4
          - device: ephemeral0.2
            filesystem: swap
        mounts:
          - ["ephemeral0.1", "/mnt/resource"]
          - ["ephemeral0.2", "none", "swap", "sw,nofail,x-systemd.device-timeout=2,x-systemd.requires=cloud-init.service", "0", "0"]
        EOF
        

14. Configure cloud-init telemetry to assist with troubleshooting for provisioning issues:

    sudo tee -a /etc/cloud/cloud.cfg.d/10-azure-kvp.cfg <<EOF
    # This config enables cloud-init to report provisioning telemetry to aid with troubleshooting
    Reporting:
      logging:
        type: log
      telemetry:
        type: hyperv
    EOF
    

15. If you want to unregister the subscription, run the following command:

    sudo subscription-manager unregister
    

16. Run the following commands to deprovision the VM and prepare it for provisioning on Azure:

    sudo cloud-init  clean --logs --seed
    sudo waagent -force -deprovision+user
    sudo rm -f ~/.bash_history
    sudo sudo rm -f /var/log/waagent.log
    sudo export HISTSIZE=0
    

    Caution

    If you're migrating a specific VM and don't want to create a generalized image, skip the deprovision step. Running the command waagent -force -deprovision+user renders the source machine unusable. This step is intended only to create a generalized image.

17. Select Action > Shut Down in Hyper-V Manager. Your Linux VHD is now ready to be uploaded to Azure.

18. Unregister the subscription (if necessary):

    sudo subscription-manager unregister
    

19. Deprovision by following the steps in "Prepare a VM from Hyper-V Manager," step 15, "Deprovision."

20. Shut down the VM in KVM.

21. Convert the qcow2 image to the VHD format.

    Note

    There's a known bug in qemu-img versions >=2.2.1 that results in an improperly formatted VHD. The issue has been fixed in QEMU 2.6. We recommend that you use either qemu-img 2.2.0 or lower, or update to 2.6 or higher. For more information, see this website.

    First convert the image to raw format:

    sudo qemu-img convert -f qcow2 -O raw rhel-[version].qcow2 rhel-[version].raw
    

    Make sure that the size of the raw image is aligned with 1 MB. Otherwise, round up the size to align with 1 MB:

    MB=$((1024*1024))
    size=$(qemu-img info -f raw --output json "rhel-[version].raw" | \
    gawk 'match($0, /"virtual-size": ([0-9]+),/, val) {print val[1]}')
    rounded_size=$((($size/$MB + 1)*$MB))
    sudo qemu-img resize rhel-[version].raw $rounded_size
    

    Convert the raw disk to a fixed-size VHD:

    sudo qemu-img convert -f raw -o subformat=fixed -O vpc rhel-[verion].raw rhel-[version].vhd
    

    Or, with qemu version 1.6+, include the force_size option:

    sudo qemu-img convert -f raw -o subformat=fixed,force_size -O vpc rhel-[version].raw rhel-[version].vhd
    

1. Create or edit the /etc/sysconfig/network file, and add the following text:

   NETWORKING=yes
   HOSTNAME=localhost.localdomain
   

2. Create or edit the /etc/sysconfig/network-scripts/ifcfg-eth0 file, and add the following text:

   DEVICE=eth0
   ONBOOT=yes
   BOOTPROTO=dhcp
   TYPE=Ethernet
   USERCTL=no
   PEERDNS=yes
   IPV6INIT=no
   PERSISTENT_DHCLIENT=yes
   NM_CONTROLLED=yes
   

   Note

   When you use Accelerated Networking, the synthetic interface that's created must be configured to be unmanaged by using a udev rule. This action prevents NetworkManager from assigning the same IP to it as the primary interface.
   

   To apply it:
   

   sudo tee <<EOF /etc/udev/rules.d/68-azure-sriov-nm-unmanaged.rules > /dev/null
   # Accelerated Networking on Azure exposes a new SRIOV interface to the VM.
   # This interface is transparently bonded to the synthetic interface,
   # so NetworkManager should just ignore any SRIOV interfaces.
   SUBSYSTEM=="net", DRIVERS=="hv_pci", ACTION!="remove", ENV{NM_UNMANAGED}="1"
   EOF
   

3. Ensure that the network service starts at boot time:

   sudo systemctl enable network
   

4. Register your Red Hat subscription to enable the installation of packages from the RHEL repository:

   sudo subscription-manager register --auto-attach --username=XXX --password=XXX
   

5. Modify the kernel boot line in your grub configuration to include more kernel parameters for Azure. To do this modification, open /etc/default/grub in a text editor and edit the GRUB_CMDLINE_LINUX parameter. For example:

   GRUB_CMDLINE_LINUX="console=ttyS0 earlyprintk=ttyS0 net.ifnames=0"
   

   This configuration ensures that all console messages are sent to the first serial port, which can assist Azure support with debugging issues. It also turns off the new RHEL 7 naming conventions for NICs. In addition, we recommend that you remove the following parameters:

   rhgb quiet crashkernel=auto
   

   Graphical and quiet boots aren't useful in a cloud environment where you want all the logs to be sent to the serial port. You can leave the crashkernel option configured if you want. This parameter reduces the amount of available memory in the VM by 128 MB or more, which might be a problem for smaller VM sizes.

6. After you're finished editing /etc/default/grub, run the following command to rebuild the grub configuration:

   sudo grub2-mkconfig -o /boot/grub2/grub.cfg
   

7. Add Hyper-V modules to initramfs:

   Edit /etc/dracut.conf, add content:

   add_drivers+=" hv_vmbus hv_netvsc hv_storvsc "
   

   Rebuild initramfs:

   sudo dracut -f -v
   

8. Ensure that the SSH server is installed and configured to start at boot time. This setting is usually the default. Modify /etc/ssh/sshd_config to include the following line:

   ClientAliveInterval 180
   

9. The WALinuxAgent package, WALinuxAgent-<version>, has been pushed to the Red Hat extras repository. Enable the extras repository:

   sudo subscription-manager repos --enable=rhel-7-server-extras-rpms
   

10. Install the Azure Linux agent:

    sudo yum install WALinuxAgent
    sudo systemctl enable waagent.service
    

11. Install cloud-init:

    Follow the steps in "Prepare a RHEL 7 VM from Hyper-V Manager," step 12, "Install cloud-init to handle the provisioning."

12. Swap configuration:

    • Don't create swap space on the operating system disk.
    • Follow the steps in "Prepare a RHEL 7 VM from Hyper-V Manager," step 13, "Swap configuration."

13. If you want to unregister the subscription, run the following command:

    sudo subscription-manager unregister
    

14. Deprovision by following the steps in "Prepare a RHEL 7 VM from Hyper-V Manager," step 15, "Deprovision."

15. Shut down the VM and convert the VMDK file to the VHD format.

    Note

    There's a known bug in qemu-img versions >=2.2.1 that results in an improperly formatted VHD. The issue has been fixed in QEMU 2.6. We recommend that you use either qemu-img 2.2.0 or lower, or update to 2.6 or higher. For more information, see this website.

    First convert the image to raw format:

    sudo qemu-img convert -f vmdk -O raw rhel-[version].vmdk rhel-[version].raw
    

    Make sure that the size of the raw image is aligned with 1 MB. Otherwise, round up the size to align with 1 MB:

    MB=$((1024*1024))
    size=$(qemu-img info -f raw --output json "rhel-[version].raw" | \
    gawk 'match($0, /"virtual-size": ([0-9]+),/, val) {print val[1]}')
    rounded_size=$((($size/$MB + 1)*$MB))
    sudo qemu-img resize rhel-[verion].raw $rounded_size
    

    Convert the raw disk to a fixed-size VHD:

    sudo qemu-img convert -f raw -o subformat=fixed -O vpc rhel-[version].raw rhel-[version].vhd
    

    Or, with qemu version 2.6+, include the force_size option:

    sudo qemu-img convert -f raw -o subformat=fixed,force_size -O vpc rhel-[version].raw rhel-[version].vhd
    
    
    

1. Ensure that the Network Manager service starts at boot time:

   sudo systemctl enable NetworkManager.service
   

2. Configure the network interface to automatically start at boot and use the Dynamic Host Configuration Protocol:

   sudo nmcli con mod eth0 connection.autoconnect yes ipv4.method auto
   

   Note

   When you use Accelerated Networking, the synthetic interface that's created must be configured to be unmanaged by using a udev rule. This action prevents NetworkManager from assigning the same IP to it as the primary interface.
   

   To apply it:
   

   sudo tee <<EOF /etc/udev/rules.d/68-azure-sriov-nm-unmanaged.rules >/dev/null
   # Accelerated Networking on Azure exposes a new SRIOV interface to the VM.
   # This interface is transparently bonded to the synthetic interface,
   # so NetworkManager should just ignore any SRIOV interfaces.
   SUBSYSTEM=="net", DRIVERS=="hv_pci", ACTION!="remove", ENV{NM_UNMANAGED}="1"
   EOF
   

3. Register your Red Hat subscription to enable the installation of packages from the RHEL repository:

   sudo subscription-manager register --auto-attach --username=XXX --password=XXX
   

4. Modify the kernel boot line in your grub configuration to include more kernel parameters for Azure and enable the serial console.

5. Remove current GRUB parameters:

   sudo grub2-editenv unset kernelopts
   

6. Edit /etc/default/grub in a text editor, and add the following parameters:

   GRUB_CMDLINE_LINUX="console=tty1 console=ttyS0,115200n8 earlyprintk=ttyS0,115200 earlyprintk=ttyS0 net.ifnames=0"
   GRUB_TERMINAL_OUTPUT="serial console"
   GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1"
   

   This modification also ensures that all console messages are sent to the first serial port and enable interaction with the serial console, which can assist Azure support with debugging issues. This configuration also turns off the new naming conventions for NICs.

7. We recommend that you also remove the following parameters:

   rhgb quiet crashkernel=auto
   

   Graphical and quiet boots aren't useful in a cloud environment where you want all the logs to be sent to the serial port. You can leave the crashkernel option configured if you want. This parameter reduces the amount of available memory in the VM by 128 MB or more, which might be a problem for smaller VM sizes.

8. After you're finished editing /etc/default/grub, run the following command to rebuild the grub configuration:

   sudo grub2-mkconfig -o /boot/grub2/grub.cfg
   

9. Add Hyper-V modules into initramfs.

   Create /etc/dracut.conf.d/azure.conf and add content:

   add_drivers+=" hv_vmbus hv_netvsc hv_storvsc "
   

   Rebuild initramfs:

   sudo dracut -f -v
   

10. Ensure that the SSH server is installed and configured to start at boot time, which is usually the default. Modify /etc/ssh/sshd_config to include the following line:

    ClientAliveInterval 180
    

11. Install the Azure Linux agent, cloud-init, and other necessary utilities:

    sudo dnf install -y WALinuxAgent cloud-init cloud-utils-growpart gdisk hyperv-daemons
    sudo systemctl enable waagent.service
    sudo systemctl enable cloud-init.service
    

12. Configure cloud-init to handle the provisioning:

    1. Configure waagent for cloud-init:

       sudo sed -i 's/Provisioning.Agent=auto/Provisioning.Agent=cloud-init/g' /etc/waagent.conf
       sudo sed -i 's/ResourceDisk.Format=y/ResourceDisk.Format=n/g' /etc/waagent.conf
       sudo sed -i 's/ResourceDisk.EnableSwap=y/ResourceDisk.EnableSwap=n/g' /etc/waagent.conf
       

       Note

       If you're migrating a specific VM and don't want to create a generalized image, set Provisioning.Agent=disabled on the /etc/waagent.conf configuration.

    2. Configure mounts:

       sudo echo "Adding mounts and disk_setup to init stage"
       sudo sed -i '/ - mounts/d' /etc/cloud/cloud.cfg
       sudo sed -i '/ - disk_setup/d' /etc/cloud/cloud.cfg
       sudo sed -i '/cloud_init_modules/a\\  - mounts' /etc/cloud/cloud.cfg
       sudo sed -i '/cloud_init_modules/a\\  - disk_setup' /etc/cloud/cloud.cfg
       

       Note

       The items for each section in the /etc/cloud/cloud.cfg file must use the same level of indentation

       Example of an incorrect setting:

       cloud_init_modules:
        - disk_setup
        - mounts 
         - migrators
       

       Example of a correct setting:

       cloud_init_modules:
         - disk_setup
         - mounts 
         - migrators
       

    3. Configure the Azure data source:

       sudo echo "Allow only Azure datasource, disable fetching network setting via IMDS"
       sudo tee /etc/cloud/cloud.cfg.d/91-azure_datasource.cfg <<EOF
       datasource_list: [ Azure ]
       datasource:
           Azure:
               apply_network_config: False
       EOF
       

    4. If configured, remove the existing swap file:

       if [[ -f /mnt/resource/swapfile ]]; then
       echo "Removing swapfile" #RHEL uses a swapfile by defaul
       swapoff /mnt/resource/swapfile
       rm /mnt/resource/swapfile -f
       fi
       

    5. Configure cloud-init logging:

       sudo echo "Add console log file"
       sudo tee <<EOF /etc/cloud/cloud.cfg.d/05_logging.cfg > /dev/null 
       
       # This tells cloud-init to redirect its stdout and stderr to
       # 'tee -a /var/log/cloud-init-output.log' so the user can see output
       # there without needing to look on the console.
       output: {all: '| tee -a /var/log/cloud-init-output.log'}
       EOF
       

13. Swap configuration:

    • Don't create swap space on the operating system disk.

      Previously, the Azure Linux agent was used to automatically configure swap space by using the local resource disk that's attached to the VM after the VM is provisioned on Azure. This action is now handled by cloud-init. You must not use the Linux agent to format the resource disk create the swap file. Modify the following parameters in /etc/waagent.conf appropriately:

      ResourceDisk.Format=n
      ResourceDisk.EnableSwap=n
      

      • Pass this code in as a cloud-init configuration every time you create a VM through custom data. We recommend this method.

      • Use a cloud-init directive baked into the image that does this step every time the VM is created.

        sudo echo 'DefaultEnvironment="CLOUD_CFG=/etc/cloud/cloud.cfg.d/00-azure-swap.cfg"' >> /etc/systemd/system.conf
        sudo tee /etc/cloud/cloud.cfg.d/00-azure-swap.cfg <<EOF
        #cloud-config
        # Generated by Azure cloud image build
        disk_setup:
          ephemeral0:
            table_type: mbr
            layout: [66, [33, 82]]
            overwrite: True
        fs_setup:
          - device: ephemeral0.1
            filesystem: ext4
          - device: ephemeral0.2
            filesystem: swap
        mounts:
          - ["ephemeral0.1", "/mnt/resource"]
          - ["ephemeral0.2", "none", "swap", "sw,nofail,x-systemd.device-timeout=2,x-systemd.requires=cloud-init.service", "0", "0"]
        EOF
        

14. Configure cloud-init telemetry to assist with troubleshooting for provisioning issues:

    sudo tee -a /etc/cloud/cloud.cfg.d/10-azure-kvp.cfg <<EOF
    # This config enables cloud-init to report provisioning telemetry to aid with troubleshooting
    Reporting:
      logging:
        type: log
      telemetry:
        type: hyperv
    EOF
    

15. If you want to unregister the subscription, run the following command:

    sudo subscription-manager unregister
    

16. Run the following commands to deprovision the VM and prepare it for provisioning on Azure:

    sudo cloud-init  clean --logs --seed
    sudo waagent -force -deprovision+user
    sudo rm -f ~/.bash_history
    sudo sudo rm -f /var/log/waagent.log
    sudo export HISTSIZE=0
    

    Caution

    If you're migrating a specific VM and don't want to create a generalized image, skip the deprovision step. Running the command waagent -force -deprovision+user renders the source machine unusable. This step is intended only to create a generalized image.

    Make sure that the size of the raw image is aligned with 1 MB. Otherwise, round up the size to align with 1 MB:

    First convert the image to raw format:

    sudo qemu-img convert -f qcow2 -O raw rhel-[version].qcow2 rhel-[version].raw
    

    Make sure that the size of the raw image is aligned with 1 MB. Otherwise, round up the size to align with 1 MB:

    MB=$((1024*1024))
    size=$(qemu-img info -f raw --output json "rhel-[version].raw" | \
    gawk 'match($0, /"virtual-size": ([0-9]+),/, val) {print val[1]}')
    rounded_size=$((($size/$MB + 1)*$MB))
    sudo qemu-img resize rhel-[version].raw $rounded_size
    

    or using jquery:

    MB=$((1024*1024))
    size=$(qemu-img info -f raw --output json "rhel-[version].raw" | jq '."virtual-size"')
    rounded_size=$((($size/$MB + 1)*$MB))
    sudo qemu-img resize -f raw rhel-[version].raw $rounded_size
    

    Convert the raw disk to a fixed-size VHD:

    sudo qemu-img convert -f raw -o subformat=fixed -O vpc rhel-[verion].raw rhel-[version].vhd
    

    Or, with qemu version 1.6+, include the force_size option:

    sudo qemu-img convert -f raw -o subformat=fixed,force_size -O vpc rhel-[version].raw rhel-[version].vhd
    

This section shows you how to prepare RHEL 7 from an ISO by using a kickstart file.

1. Create a kickstart file that includes the following content and save the file. For information about kickstart installation, see the Kickstart Installation Guide.

   # Kickstart for provisioning a  Azure VM
   
   # System authorization information
     auth --enableshadow --passalgo=sha512
   
   # Use graphical install
   text
   
   # Don't run the Setup Agent on first boot
   firstboot --disable
   
   # Keyboard layouts
   keyboard --vckeymap=us --xlayouts='us'
   
   # System language
   lang en_US.UTF-8
   
   # Network information
   network  --bootproto=dhcp
   
   # Root password
   rootpw --plaintext "to_be_disabled"
   
   # System services
   services --enabled="sshd,waagent,NetworkManager"
   
   # System timezone
   timezone Etc/UTC --isUtc --ntpservers 0.rhel.pool.ntp.org,1.rhel.pool.ntp.org,2.rhel.pool.ntp.org,3.rhel.pool.ntp.org
   
   # Partition clearing information
   clearpart --all --initlabel
   
   # Clear the MBR
   zerombr
   
   # Disk partitioning information
   part /boot --fstype="xfs" --size=500
   part / --fstyp="xfs" --size=1 --grow --asprimary
   
   # System bootloader configuration
   bootloader --location=mbr
   
   # Firewall configuration
   firewall --disabled
   
   # Enable SELinux
   selinux --enforcing
   
   # Don't configure X
   skipx
   
   # Power down the machine after install
   poweroff
   
   %packages
   @base
   @console-internet
   chrony
   sudo
   parted
   -dracut-config-rescue
   
   %end
   
   %post --log=/var/log/anaconda/post-install.log
   
   #!/bin/bash
   
   # Register Red Hat Subscription
   subscription-manager register --username=XXX --password=XXX --auto-attach --force
   
   # Install latest repo update
   yum update -y
   
   # Enable extras repo
   subscription-manager repos --enable=rhel-7-server-extras-rpms
   
   # Install WALinuxAgent
   yum install -y WALinuxAgent
   
   # Unregister Red Hat subscription
   subscription-manager unregister
   
   # Enable waaagent at boot-up
   systemctl enable waagent
   
   # Install cloud-init
   yum install -y cloud-init cloud-utils-growpart gdisk hyperv-daemons
   
   # Configure waagent for cloud-init
   sed -i 's/Provisioning.Agent=auto/Provisioning.Agent=cloud-init/g' /etc/waagent.conf
   sed -i 's/ResourceDisk.Format=y/ResourceDisk.Format=n/g' /etc/waagent.conf
   sed -i 's/ResourceDisk.EnableSwap=y/ResourceDisk.EnableSwap=n/g' /etc/waagent.conf
   
   echo "Adding mounts and disk_setup to init stage"
   sed -i '/ - mounts/d' /etc/cloud/cloud.cfg
   sed -i '/ - disk_setup/d' /etc/cloud/cloud.cfg
   sed -i '/cloud_init_modules/a\\ - mounts' /etc/cloud/cloud.cfg
   sed -i '/cloud_init_modules/a\\ - disk_setup' /etc/cloud/cloud.cfg
   
   # Disable the root account
   usermod root -p '!!'
   
   # Configure swap using cloud-init
   echo 'DefaultEnvironment="CLOUD_CFG=/etc/cloud/cloud.cfg.d/00-azure-swap.cfg"' >> /etc/systemd/system.conf
   sudo tee /etc/cloud/cloud.cfg.d/00-azure-swap.cfg <<EOF
   #cloud-config
   # Generated by Azure cloud image build
   disk_setup:
   ephemeral0:
       table_type: mbr
       layout: [66, [33, 82]]
       overwrite: True
   fs_setup:
   - device: ephemeral0.1
       filesystem: ext4
   - device: ephemeral0.2
       filesystem: swap
   mounts:
   - ["ephemeral0.1", "/mnt"]
   - ["ephemeral0.2", "none", "swap", "sw,nofail,x-systemd.device-timeout=2,x-systemd.requires=cloud-init.service", "0", "0"]
   EOF
   
   # Set the cmdline
   sed -i 's/^\(GRUB_CMDLINE_LINUX\)=".*"$/\1="console=tty1 console=ttyS0 earlyprintk=ttyS0"/g' /etc/default/grub
   
   # Enable SSH keepalive
   sed -i 's/^#\(ClientAliveInterval\).*$/\1 180/g' /etc/ssh/sshd_config
   
   # Build the grub cfg
   grub2-mkconfig -o /boot/grub2/grub.cfg
   
   # Configure network
   tee <<EOF /etc/sysconfig/network-scripts/ifcfg-eth0 > /dev/null
   DEVICE=eth0
   ONBOOT=yes
   BOOTPROTO=dhcp
   TYPE=Ethernet
   USERCTL=no
   PEERDNS=yes
   IPV6INIT=no
   PERSISTENT_DHCLIENT=yes
   NM_CONTROLLED=yes
   EOF
   
   sudo tee <<EOF /etc/udev/rules.d/68-azure-sriov-nm-unmanaged.rules >/dev/null
   # Accelerated Networking on Azure exposes a new SRIOV interface to the VM.
   # This interface is transparently bonded to the synthetic interface,
   # so NetworkManager should just ignore any SRIOV interfaces.
   SUBSYSTEM=="net", DRIVERS=="hv_pci", ACTION!="remove", ENV{NM_UNMANAGED}="1"
   EOF
   
   # Deprovision and prepare for Azure if you are creating a generalized image
   sudo cloud-init clean --logs --seed
   sudo rm -rf /var/lib/cloud/
   sudo rm -rf /var/lib/waagent/
   sudo rm -f /var/log/waagent.log
   
   sudo waagent -force -deprovision+user
   rm -f ~/.bash_history
   export HISTSIZE=0
   
   %end
   

2. Place the kickstart file where the installation system can access it.

3. In Hyper-V Manager, create a new VM. On the Connect Virtual Hard Disk page, select Attach a virtual hard disk later, and complete the New Virtual Machine wizard.

4. Open the VM settings:

   1. Attach a new VHD to the VM. Make sure to select VHD Format and Fixed Size.

   2. Attach the installation ISO to the DVD drive.

   3. Set the BIOS to boot from CD.

5. Start the VM. When the installation guide appears, select the Tab key to configure the boot options.

6. Enter inst.ks=<the location of the kickstart file> at the end of the boot options, and select the Enter key.

7. Wait for the installation to finish. When it's finished, the VM shuts down automatically. Your Linux VHD is now ready to be uploaded to Azure.

Known issues

The following issue is known.

The Hyper-V driver couldn't be included in the initial RAM disk when using a non-Hyper-V hypervisor

In some cases, Linux installers might not include the drivers for Hyper-V in the initial RAM disk (initrd or initramfs) unless Linux detects that it's running in a Hyper-V environment.

When you're using a different virtualization system (for example, VirtualBox or Xen) to prepare your Linux image, you might need to rebuild initrd to ensure that at least the hv_vmbus and hv_storvsc kernel modules are available on the initial RAM disk. This issue is known, at least on systems that are based on the upstream Red Hat distribution.

To resolve this issue, add Hyper-V modules to initramfs and rebuild it:

Edit /etc/dracut.conf, and add the following content:

add_drivers+=" hv_vmbus hv_netvsc hv_storvsc "

Rebuild initramfs:

sudo dracut -f -v

This section shows you how to prepare RHEL (8 OR 9) from an ISO by using a kickstart file.

1. Create a kickstart file that includes the following content and save the file. For information about kickstart installation, see the Kickstart Installation Guide.

   # Kickstart for provisioning a  Azure VM
   
   # System authorization information
     auth --enableshadow --passalgo=sha512
   
   # Use graphical install
   text
   
   # Don't run the Setup Agent on first boot
   firstboot --disable
   
   # Keyboard layouts
   keyboard --vckeymap=us --xlayouts='us'
   
   # System language
   lang en_US.UTF-8
   
   # Network information
   network  --bootproto=dhcp
   
   # Root password
   rootpw --plaintext "to_be_disabled"
   
   # System services
   services --enabled="sshd,waagent,NetworkManager"
   
   # System timezone
   timezone Etc/UTC --isUtc --ntpservers 0.rhel.pool.ntp.org,1.rhel.pool.ntp.org,2.rhel.pool.ntp.org,3.rhel.pool.ntp.org
   
   # Partition clearing information
   clearpart --all --initlabel
   
   # Clear the MBR
   zerombr
   
   # Disk partitioning information
   part /boot --fstype="xfs" --size=500
   part / --fstyp="xfs" --size=1 --grow --asprimary
   
   # System bootloader configuration
   bootloader --location=mbr
   
   # Firewall configuration
   firewall --disabled
   
   # Enable SELinux
   selinux --enforcing
   
   # Don't configure X
   skipx
   
   # Power down the machine after install
   poweroff
   
   %packages
   @base
   @console-internet
   chrony
   sudo
   parted
   -dracut-config-rescue
   
   %end
   
   %post --log=/var/log/anaconda/post-install.log
   
   #!/bin/bash
   
   # Register Red Hat Subscription
   subscription-manager register --username=XXX --password=XXX --auto-attach --force
   
   # Install latest repo update
   yum update -y
   
   # Enable extras repo
   subscription-manager repos --enable=rhel-[version]-server-extras-rpms
   
   # Install WALinuxAgent
   yum install -y WALinuxAgent
   
   # Unregister Red Hat subscription
   subscription-manager unregister
   
   # Enable waaagent at boot-up
   systemctl enable waagent
   
   # Install cloud-init
   yum install -y cloud-init cloud-utils-growpart gdisk hyperv-daemons
   
   # Configure waagent for cloud-init
   sed -i 's/Provisioning.Agent=auto/Provisioning.Agent=cloud-init/g' /etc/waagent.conf
   sed -i 's/ResourceDisk.Format=y/ResourceDisk.Format=n/g' /etc/waagent.conf
   sed -i 's/ResourceDisk.EnableSwap=y/ResourceDisk.EnableSwap=n/g' /etc/waagent.conf
   
   echo "Adding mounts and disk_setup to init stage"
   sed -i '/ - mounts/d' /etc/cloud/cloud.cfg
   sed -i '/ - disk_setup/d' /etc/cloud/cloud.cfg
   sed -i '/cloud_init_modules/a\\ - mounts' /etc/cloud/cloud.cfg
   sed -i '/cloud_init_modules/a\\ - disk_setup' /etc/cloud/cloud.cfg
   
   # Disable the root account
   usermod root -p '!!'
   
   # Configure swap using cloud-init
   sudo echo 'DefaultEnvironment="CLOUD_CFG=/etc/cloud/cloud.cfg.d/00-azure-swap.cfg"' >> /etc/systemd/system.conf
   sudo tee /etc/cloud/cloud.cfg.d/00-azure-swap.cfg <<EOF
   #cloud-config
   # Generated by Azure cloud image build
   disk_setup:
   ephemeral0:
       table_type: mbr
       layout: [66, [33, 82]]
       overwrite: True
   fs_setup:
   - device: ephemeral0.1
       filesystem: ext4
   - device: ephemeral0.2
       filesystem: swap
   mounts:
   - ["ephemeral0.1", "/mnt"]
   - ["ephemeral0.2", "none", "swap", "sw,nofail,x-systemd.device-timeout=2,x-systemd.requires=cloud-init.service", "0", "0"]
   EOF
   
   # Configure `cloud-init` telemetry to assist with troubleshooting for provisioning issues:
   
   sudo tee /etc/cloud/cloud.cfg.d/10-azure-kvp.cfg <<EOF
   # This config enables cloud-init to report provisioning telemetry to aid with troubleshooting
     Reporting:
       logging:
          type: log
       telemetry:
          type: hyperv
   EOF
   
   # Set the cmdline
   sed -i 's/^\(GRUB_CMDLINE_LINUX\)=".*"$/\1="console=tty1 console=ttyS0 earlyprintk=ttyS0"/g' /etc/default/grub
   
   # Enable SSH keepalive
   sed -i 's/^#\(ClientAliveInterval\).*$/\1 180/g' /etc/ssh/sshd_config
   
   # Build the grub cfg
   grub2-mkconfig -o /boot/grub2/grub.cfg
   
   # Configure network
   tee <<EOF /etc/sysconfig/network-scripts/ifcfg-eth0 > /dev/null
   DEVICE=eth0
   ONBOOT=yes
   BOOTPROTO=dhcp
   TYPE=Ethernet
   USERCTL=no
   PEERDNS=yes
   IPV6INIT=no
   PERSISTENT_DHCLIENT=yes
   NM_CONTROLLED=yes
   EOF
   
   sudo tee <<EOF /etc/udev/rules.d/68-azure-sriov-nm-unmanaged.rules >/dev/null
   # Accelerated Networking on Azure exposes a new SRIOV interface to the VM.
   # This interface is transparently bonded to the synthetic interface,
   # so NetworkManager should just ignore any SRIOV interfaces.
   SUBSYSTEM=="net", DRIVERS=="hv_pci", ACTION!="remove", ENV{NM_UNMANAGED}="1"
   EOF
   
   # Deprovision and prepare for Azure if you are creating a generalized image
   sudo cloud-init clean --logs --seed
   sudo rm -rf /var/lib/cloud/
   sudo rm -rf /var/lib/waagent/
   sudo rm -f /var/log/waagent.log
   
   sudo waagent -force -deprovision+user
   rm -f ~/.bash_history
   export HISTSIZE=0
   
   %end
   

2. Place the kickstart file where the installation system can access it.

3. In Hyper-V Manager, create a new VM. On the Connect Virtual Hard Disk page, select Attach a virtual hard disk later, and complete the New Virtual Machine wizard.

4. Open the VM settings:

   1. Attach a new VHD to the VM. Make sure to select VHD Format and Fixed Size.

   2. Attach the installation ISO to the DVD drive.

   3. Set the BIOS to boot from CD.

5. Start the VM. When the installation guide appears, select the Tab key to configure the boot options.

6. Enter inst.ks=<the location of the kickstart file> at the end of the boot options, and select the Enter key.

7. Wait for the installation to finish. When it's finished, the VM shuts down automatically. Your Linux VHD is now ready to be uploaded to Azure.

Known issues

The following issue is known.

The Hyper-V driver couldn't be included in the initial RAM disk when using a non-Hyper-V hypervisor

In some cases, Linux installers might not include the drivers for Hyper-V in the initial RAM disk (initrd or initramfs) unless Linux detects that it's running in a Hyper-V environment.

When you're using a different virtualization system (for example, VirtualBox or Xen) to prepare your Linux image, you might need to rebuild initrd to ensure that at least the hv_vmbus and hv_storvsc kernel modules are available on the initial RAM disk. This issue is known, at least on systems that are based on the upstream Red Hat distribution.

To resolve this issue, add Hyper-V modules to initramfs and rebuild it:

Edit /etc/dracut.conf, and add the following content:

add_drivers+=" hv_vmbus hv_netvsc hv_storvsc "

Rebuild initramfs:

sudo dracut -f -v