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Deploying SLE Micro using Raw Disk Images on IBM Z DASD Disks

Publication Date: 28 Sep 2024
WHAT?

SUSE Linux Enterprise Micro provides raw images (also referred to as pre-built images) that can be deployed directly to your device storage.

WHY?

This article provides you with step-by-step instructions on deploying SUSE Linux Enterprise Micro on an IBM Z machine.

EFFORT

It takes approximately 20 minutes to read the article.

GOAL

SUSE Linux Enterprise Micro is successfully deployed on your system.

REQUIREMENTS
  • A disk with running Linux.

  • A disk where you deploy the raw image and where SUSE Linux Enterprise Micro will run.

  • A disk that serves as a configuration medium.

1 About pre-built images

Pre-built images are ready-to-use representations of a running operating system. They are not installed in a traditional way using an installer, but copied to the hard disk of the target host. The topic covers basic information about these pre-built images.

The pre-built images are intended to be configured on the first boot by using tools delivered in the images. The boot loader detects the first boot as described in Section 1.1, “First boot detection”.

1.1 First boot detection

The deployment configuration runs on the first boot only. To distinguish between the first and subsequent boots, the file /etc/machine-id is created after the first boot finishes. If the file is not present in the file system, the system assumes that this is a first boot and triggers the configuration process. After completing the first boot, the /etc/machine-id file is created.

Note
Note: The /etc/machine-id file is always created

Even though the configuration may not be successful because of improper or missing configuration files, the /etc/machine-id file is created.

1.1.1 Force system reconfiguration on a subsequent boot

If you need to reconfigure your system after the first boot happened, you can force the reconfiguration on the subsequent boot. Here you have two options.

  • You can pass the ignition.firstboot or combustion.firstboot attribute to the kernel command line.

  • You can delete the file /etc/machine-id and reboot the system.

2 Deployment of SLE Micro

The deployment procedure of SLE Micro comprises three phases. Do not skip any of the phases and follow the order as stated below.

  1. DASD disks activation—before you start the deployment, you need to ensure that all disks to be used are available and active. For details, refer to Section 3, “Preparing the machine”.

  2. Preparing a configuration device—to configure the network, add users and register the system, prepare the configuration according to the instructions provided in Section 4, “Preparing the configuration disk”.

  3. Downloading the SLE Micro image and deploying it on the disk. For details, refer to Section 5, “Deploying the raw disk image on the DASD disk”.

3 Preparing the machine

Before you start deploying SLE Micro, you need to check if all the three needed DASD disks are active. To check the disks' state, run the command:

# lsdasd

Bus-ID    Status    Name      Device  Type         BlkSz  Size      Blocks 
================================================================================ 
0.0.0100  active    dasda     94:0    ECKD         4096   30720MB   7864380 
0.0.0101  active    dasdc     94:8    ECKD         4096   20480MB   5243040
0.0.0102  active    dasdb     94:4    ECKD         4096   5120MB    1310760

The 5 GB disk will be used as a configuration device, and the 20 GB disk is the disk where SUSE Linux Enterprise Micro will be deployed.

If you do not see the disks in the command output, you need to activate the disks. To do so, proceed as follows:

  1. Run the lszdev dasd to display a full list of devices:

    # lszdev dasd
    
    TYPE       ID        ON   PERS  NAMES 
    dasd-eckd  0.0.0100  yes  no    dasda 
    dasd-eckd  0.0.0101  no   no    
    dasd-eckd  0.0.0102  no   no   
    dasd-eckd  0.0.0190  no   no     
    dasd-eckd  0.0.019d  no   no     
    dasd-eckd  0.0.019e  no   no     
    dasd-eckd  0.0.0592  no   no
  2. Activate the disks by using the command:

    # chzdev -e DISK_ID

    For example, to activate the disk 0.0.0101:

    # chzdev -e 0.0.0101
  3. Verify that the disks are active in the output of the lsdasd command.

4 Preparing the configuration disk

Tip
Tip: Virtual versus physical disk

A virtual disk may be more suitable for production deployments, while a physical disk is better suited for development.

During the installation process, you can pass a complex configuration to define users, directories, or to provide SSH keys. To do so, create a configuration device that stores a complete configuration. The following example procedure describes how to create such a device:

  1. Identify the 5 GB disk:

    # lsdasd
    
    Bus-ID    Status    Name      Device  Type         BlkSz  Size      Blocks 
    ================================================================================ 
    0.0.0100  active    dasda     94:0    ECKD         4096   30720MB   7864380 
    0.0.0101  active    dasdc     94:8    ECKD         4096   20480MB   5243040
    0.0.0102  active    dasdb     94:4    ECKD         4096   5120MB    1310760

    In the output above, the Bus-ID value of the disk to be used as a configuration device is 0.0.0102. Use the value of Bus-ID or the disk size to identify the disk, as the device name (/dev/dasdX) can change after each reboot.

  2. Format the disk. Keep in mind that formatting removes all data on that disk.

    # dasdfmt -b 4096 -y -p /dev/dasdb
  3. Create a partition:

    # parted /dev/dasdb mkpart ext2 0% 100%
  4. Format the partition:

    # mkfs.ext4 /dev/dasdb1
  5. Label the partition as ignition:

    # e2label /dev/dasdb1 ignition
  6. Verify the file system:

    # blkid
  7. Mount the partition:

    # mount /dev/dasdb1 /mnt
  8. Prepare the directory structure for Ignition and/or Combustion. For Ignition:

    # mkdir -p  /mnt/ignition

    For Combustion:

    # mkdir -p /mnt/combustion
  9. Copy your public SSH key to /mnt/combustion as ssh_key.pub.

  10. Prepare the configuration as described further.

4.1 Configuring SLE Micro deployment with Combustion

Combustion is a dracut module that enables you to configure your system on the first boot. You can use Combustion, for example, to change the default partitions, set user passwords, create files, or install packages.

4.1.1 How does Combustion work?

Combustion is invoked after the ignition.firstboot argument is passed to the kernel command line. Combustion reads a provided file named script, executes included commands, and thus performs changes to the file system. If script includes the network flag, Combustion tries to configure the network. After /sysroot is mounted, Combustion tries to activate all mount points in /etc/fstab and then calls transactional-update to apply other changes, for example, setting root password or installing packages.

The configuration file script must reside in the combustion subdirectory on the configuration media labeled combustion. The directory structure must look as follows:

<root directory>
└── combustion
    └── script
    └── other files
Tip
Tip: Using Combustion together with Ignition

Combustion can be used along with Ignition. If you intend to do so, label your configuration medium ignition and include the ignition directory with the config.ign to your directory structure as shown below:

<root directory>
└── combustion
    └── script
    └── other files
└── ignition
    └── config.ign

In this scenario, Ignition runs before Combustion.

4.1.2 Combustion configuration examples

4.1.2.1 The script configuration file

The script configuration file is a set of commands that are parsed and executed by Combustion in a transactional-update shell. This article provides examples of configuration tasks performed by Combustion.

Important
Important: Include interpreter declaration

As the script file is interpreted by the shell, always start the file with the interpreter declaration on its first line. For example, in case of Bash:

#!/bin/bash

To log in to your system, include at least the root password. However, it is recommended to establish the authentication using SSH keys. If you need to use a root password, make sure to configure a secure password. For a randomly generated password, use at least 10 characters. If you create your password manually, use even more than 10 characters and combine uppercase and lowercase letters and numbers.

4.1.2.1.1 Default partitioning

Each image has the following subvolumes:

/home
/root
/opt
/srv
/usr/local
/var

The /etc directory is mounted as overlayFS, where the upper directory is mounted to /var/lib/overlay/1/etc/.

You can recognize the subvolumes mounted by default by the option x-initrd.mount in /etc/fstab. Other subvolumes or partitions must be configured either by Ignition or Combustion.

If you want to add a new user or modify any of the files on a subvolume that is not mounted by default, you need to declare such subvolume first so that it is mounted as well.

4.1.2.1.2 Network configuration

To configure and use the network connection during the first boot, add the following statement to script:

# combustion: network

Using this statement passes the rd.neednet=1 argument to dracut. The network configuration defaults to using DHCP. If a different network configuration is needed, proceed as described in Section 4.1.2.1.3, “Performing modifications in the initramfs”.

If you do not use the statement, the system remains configured without any network connection.

4.1.2.1.3 Performing modifications in the initramfs

You may need to perform changes to the initramfs environment, for example, to write a custom network configuration for NetworkManager into /etc/NetworkManager/system-connections/. To do so, use the prepare statement.

For example, to create a connection with a static IP address and configure DNS:

#!/bin/bash
# combustion: network prepare
set -euxo pipefail
          
nm_config() {
  umask 077 # Required for NM config
  mkdir -p /etc/NetworkManager/system-connections/
  cat >/etc/NetworkManager/system-connections/static.nmconnection <<-EOF
  [connection]
  id=static
  type=ethernet
  autoconnect=true
          
  [ipv4]
  method=manual
  dns=192.168.100.1
  address1=192.168.100.42/24,192.168.100.1
EOF
}
          
if [ "${1-}" = "--prepare" ]; then
  nm_config # Configure NM in the initrd
  exit 0
fi
          
# Redirect output to the console
exec > >(exec tee -a /dev/tty0) 2>&1
          
  nm_config # Configure NM in the system
  curl example.com

# Close outputs and wait for tee to finish
exec 1>&- 2>&-; wait;

# Leave a marker
echo "Configured with combustion" > /etc/issue.d/combustion
4.1.2.1.4 Waiting for the task to complete

Some processes may be run in background, for example, the tee process that redirects output to the terminal. To ensure that all running processes are completed before the script execution finishes, add the following line:

exec 1>&- 2>&-; wait;
4.1.2.1.5 Partitioning

SLE Micro raw images are delivered with a default partitioning scheme. You might want to use a different partitioning. The following set of example snippets moves the /home to a different partition.

Note
Note: Performing changes outside of directories included in snapshots

The following script performs changes that are not included in snapshots. If the script fails and the snapshot is discarded, certain changes remain visible and cannot be reverted, for example, the changes to the /dev/vdb device.

The following snippet creates a GPT partitioning schema with a single partition on the /dev/vdb device:

sfdisk /dev/vdb <<EOF
sleep 1
label: gpt
type=linux
EOF

partition=/dev/vdb1

As the sfdisk command may take longer time to complete, postpone label by using the sleep command after sfdisk.

The partition is formatted to Btrfs:

wipefs --all ${partition}
mkfs.btrfs ${partition}

Possible content of /home is moved to the new /home folder location by the following snippet:

mount /home
mount ${partition} /mnt
rsync -aAXP /home/ /mnt/
umount /home /mnt

The snippet below removes an old entry in /etc/fstab and creates a new entry:

awk -i inplace '$2 != "/home"' /etc/fstab
echo "$(blkid -o export ${partition} | grep ^UUID=) /home btrfs defaults 0 0" >>/etc/fstab
4.1.2.1.6 Creating new users

As some services, such as Cockpit, require login using a non-root user, define at least one unprivileged user here. Alternatively, you can create such a user from a running system as described in Section 6.2, “Adding users”.

To add a new user account, first create a hash string that represents the user's password. Use the openssl passwd -6 command.

After you obtain the password hash, add the following lines to the script:

mount /home
useradd -m EXAMPLE_USER
echo 'EXAMPLE_USER:PASSWORD_HASH' | chpasswd -e
4.1.2.1.7 Setting a password for root

Before you set the root password, generate a hash of the password, for example, by using the openssl passwd -6. To set the password, add the following line to the script:

echo 'root:PASSWORD_HASH' | chpasswd -e
4.1.2.1.8 Adding SSH keys

The following snippet creates a directory to store the root's SSH key and then copies the public SSH key located on the configuration device to the authorized_keys file.

mkdir -pm700 /root/.ssh/
cat id_rsa_new.pub >> /root/.ssh/authorized_keys
Note
Note

The SSH service must be enabled in case you need to use remote login via SSH. For details, refer to Section 4.1.2.1.9, “Enabling services”.

4.1.2.1.9 Enabling services

To enable system services, for example, the SSH service, add the following line to script:

systemctl enable sshd.service
4.1.2.1.10 Installing packages
Important
Important: Network connection and registering your system may be necessary

As certain packages may require additional subscription, you may need to register your system beforehand. An available network connection may also be needed to install additional packages.

During the first boot configuration, you can install additional packages to your system. For example, you can install the vim editor by adding:

zypper --non-interactive install vim-small
Note
Note

Bear in mind that you will not be able to use zypper after the configuration is complete and you boot to the configured system. To perform changes later, you must use the transactional-update command to create a changed snapshot.

4.1.2.2 A complete example of the script file

The following script provides complete settings that may serve you as a guide on how to write your own Combustion configuration. The example does not require any further Ignition configuration.

    #!/bin/bash
    # combustion: network prepare
    
    
    set -euxo pipefail
    
    ## The OSA subchannels to enable
    ZNET_SUBCHANNELS=0.0.1000,0.0.1001,0.0.1002
    
    ## Network information to configure
    IPADDRESS="10.144.64.155/24" ## Formet is ipaddress/cidr
    GATEWAY="10.144.64.254"
    NAMESERVERS="10.144.53.53;10.144.53.54" ## A semicolon-separated list of name servers
    
    ## Hostname information
    NODE_HOSTNAME="micro6"
    
    ## Add password for root user
    ## Use either 'openssl passwd -6' or 'mkpasswd --method=sha-512' to encrypt the password.
    ROOT_USER_PASSWORD='PASSWORD_HASH'
    SSH_ROOT_PUBLIC_KEY=ssh_key.pub
    
    ## Add a regular user, because root login may be disallowed in some services.
    CREATE_NORMAL_USER=user ## Replace the "user" with a desired username here.
    NORMAL_USER_PASSWORD='PASSWORD_HASH'
    SSH_USER_PUBLIC_KEY=ssh_key.pub
    
    ## Register to SUSE Customer Center and install additional packages
    REG_EMAIL='tux@suse.com' ## Email address for product registration
    SLMICRO_REGCODE='REGISTRATIONCODE' ## A registration code required to install additional packages
    ADDITIONAL_PACKAGES='' ## A space separated list of additional packages to install
    
    
    nm_config() {
      umask 077 # Required for Network Manager configuration
      mkdir -p /etc/NetworkManager/system-connections/
      cat >'/etc/NetworkManager/system-connections/Wired connection 1.nmconnection' <<EOF
      [connection]
      id=static
      type=ethernet
      autoconnect=true
    
      [ipv4]
      method=manual
      address1=$IPADDRESS
      gateway=$GATEWAY
      dns=$NAMESERVERS
    EOF
    }
    
    if [ "${1-}" = "--prepare" ]; then
      # Configure Network Manager in the initrd
      nm_config
      # Enable OSA network devices
      chzdev qeth $ZNET_SUBCHANNELS -ep
      chzdev qeth $ZNET_SUBCHANNELS -e    
      exit 0
    fi
    
    
    
    ## Post output on stdout
    exec > >(exec tee -a /dev/ttyS0) 2>&1
    
    ## Set hostname
    echo $NODE_HOSTNAME > /etc/hostname
    
    ## Set root password
    echo root:$ROOT_USER_PASSWORD | chpasswd -e
    ## Add ssh public key as authorized key for the root user
    mkdir -pm700 /root/.ssh/
    cat $SSH_ROOT_PUBLIC_KEY >> /root/.ssh/authorized_keys
    
    ## Mount /var and /home so user can be created smoothly
    if [ "$CREATE_NORMAL_USER" ]
    then
      mount /var && mount /home
    fi
    ## User creation
    if [ "$CREATE_NORMAL_USER" ]
    then
      echo "User creation is requested, creating user."
      useradd -m $CREATE_NORMAL_USER -s /bin/bash -g users
      echo $CREATE_NORMAL_USER:$NORMAL_USER_PASSWORD | chpasswd -e
      echo $CREATE_NORMAL_USER "ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers.d/adminusers
      mkdir -pm700 /home/$CREATE_NORMAL_USER/.ssh/
      chown -R $CREATE_NORMAL_USER:users /home/$CREATE_NORMAL_USER/.ssh/
      cat $SSH_USER_PUBLIC_KEY >> /home/$CREATE_NORMAL_USER/.ssh/authorized_keys
      echo "Requested user has been created, requested password has been set."
    else
      echo "No user will be created"
    fi
    
    # Configure NM in the system
    nm_config
    # Enable OSA network device
    chzdev qeth $ZNET_SUBCHANNELS -ep
    chzdev qeth $ZNET_SUBCHANNELS -e
    
    ## Enable services
    echo "Enabling services."
    systemctl enable cockpit.socket
    systemctl enable sshd
    
    ## Unmount var and home
    if [ "$CREATE_NORMAL_USER" ]
    then
      umount /var && umount /home
    fi  
    
    # Close outputs and wait for tee to finish
    exec 1>&- 2>&-; wait;
    
    echo "Configured with Combustion at $(date)" > /etc/issue.d/combustion

4.2 Configuring SLE Micro deployment with Ignition

Ignition is a provisioning tool that enables you to configure a system according to your specification on the first boot.

4.2.1 How does Ignition work?

When the system is booted for the first time, Ignition is loaded as part of an initramfs and searches for a configuration file within a specific directory (on a USB flash disk, or you can provide a URL). All changes are performed before the kernel switches from the temporary file system to the real root file system (before the switch_root command is issued).

Ignition uses a configuration file in the JSON format named config.ign. You can either write the configuration manually or use the Fuel Ignition Web application at https://ignite.opensuse.org to generate it.

Important
Important

Fuel Ignition does not cover the complete Ignition vocabulary yet, and the resulting JSON file may need additional manual tweaking.

4.2.1.1 config.ign

The configuration file config.ign must reside in the ignition subdirectory on the configuration media, for example, a USB stick labeled ignition. The directory structure must look as follows:

<root directory>
└── ignition
    └── config.ign
Tip
Tip

To create a disk image with the Ignition configuration, you can use the Fuel Ignition Web application at https://ignite.opensuse.org.

The config.ign contains multiple data types: objects, strings, integers, booleans and lists of objects. For a complete specification, refer to Ignition specification v3.3.0.

The version attribute is mandatory and in case of SLE Micro, its value must be set either to 3.4.0 or to any lower version. Otherwise, Ignition will fail.

To log in to your system as root, you must at least include a password for root. However, it is recommended to establish access via SSH keys. To configure a password, make sure to use a secure one. If you use a randomly generated password, use at least 10 characters. If you create your password manually, use even more than 10 characters and combine uppercase and lowercase letters and numbers.

4.2.2 Ignition configuration examples

This section provides several examples of the Ignition configuration in the built-in JSON format.

Note
Note: The version attribute is mandatory

Each config.ign must include version 3.4.0 or lower that is then converted to the corresponding Ignition specification.

4.2.2.1 Default partitioning

Each image has the following subvolumes:

/home
/root
/opt
/srv
/usr/local
/var

The /etc directory is mounted as overlayFS, where the upper directory is mounted to /var/lib/overlay/1/etc/.

You can recognize the subvolumes mounted by default by the option x-initrd.mount in /etc/fstab. Other subvolumes or partitions must be configured either by Ignition or Combustion.

If you want to add a new user or modify any of the files on a subvolume that is not mounted by default, you need to declare such subvolume first so that it is mounted as well.

4.2.2.2 Storage configuration

The storage attribute is used to configure partitions, RAID, define file systems, create files, etc. To define partitions, use the disks attribute. The filesystems attribute is used to format partitions. The files attribute can be used to create files in the file system. Each of the mentioned attributes is described in the following sections.

4.2.2.2.1 The disks attribute

The disks attribute is a list of devices that enables you to define partitions on these devices. The disks attribute must contain at least one device, other attributes are optional. The following example uses a single virtual device and divides the disk into four partitions:

{
  "ignition": {
    "version": "3.0.0"
  },
  "storage": {
    "disks": [
      {
        "device": "/dev/vda",
        "partitions": [
          {
            "label": "root",
            "number": 1,
            "typeGuid": "4F68BCE3-E8CD-4DB1-96E7-FBCAF984B709"
          },
          {
            "label": "boot",
            "number": 2,
            "typeGuid": "BC13C2FF-59E6-4262-A352-B275FD6F7172"
          },
          {
            "label": "swap",
            "number": 3,
            "typeGuid": "0657FD6D-A4AB-43C4-84E5-0933C84B4F4F"
          },
          {
            "label": "home",
            "number": 4,
            "typeGuid": "933AC7E1-2EB4-4F13-B844-0E14E2AEF915"
          }
        ],
        "wipeTable": true
      }
    ]
  }
}
4.2.2.2.2 The raid attribute

The raid is a list of RAID arrays. The following attributes of raid are mandatory:

level

a level of the particular RAID array (linear, raid0, raid1, raid2, raid3, raid4, raid5, raid6)

devices

a list of devices in the array referenced by their absolute paths

name

a name that will be used for the md device

For example:

{
  "ignition": {
    "version": "3.0.0"
  },
  "storage": {
    "raid": [
      {
        "devices": [
          "/dev/sda",
          "/dev/sdb"
        ],
        "level": "raid1",
        "name": "system"
      }
    ]
  }
}
4.2.2.2.3 The filesystems attribute
Note
Note: Ignition does not perform modifications to mount units

The file system attribute does not modify mount units. If you add a new partition or remove an existing partition, you must manually adjust the mount units.

filesystems must contain the following attributes:

device

the absolute path to the device, typically /dev/sda in case of physical disk

format

the file system format (Btrfs, Ext4, xfs, vfat or swap)

Note
Note

In case of SLE Micro, the root file system must be formatted to Btrfs.

The following example demonstrates using the filesystems attribute. The /opt directory will be mounted to the /dev/sda1 partition, which is formatted to Btrfs. The device will not be erased.

For example:

{
  "ignition": {
    "version": "3.0.0"
  },
  "storage": {
    "filesystems": [
      {
        "device": "/dev/sda1",
        "format": "btrfs",
        "path": "/opt",
        "wipeFilesystem": false
      }
    ]
  }
}

Normally, a regular user's home directory is located in the /home/USER_NAME directory. Since /home is not mounted by default in the initrd, the mount has to be explicitly defined for the user creation to succeed:

{
  "ignition": {
    "version": "3.1.0"
  },
  "passwd": {
    "users": [
      {
        "name": "root",
        "passwordHash": "PASSWORD_HASH",
        "sshAuthorizedKeys": [
          "ssh-rsa SSH_KEY_HASH"
        ]
      }
    ]
  },
  "storage": {
    "filesystems": [
      {
        "device": "/dev/sda3",
        "format": "btrfs",
        "mountOptions": [
          "subvol=/@/home"
        ],
        "path": "/home",
        "wipeFilesystem": false
      }
    ]
  }
}
4.2.2.2.4 The files attribute

You can use the files attribute to create any files on your machine. Bear in mind that to create files outside the default partitioning schema, you need to define the directories by using the filesystems attribute.

In the following example, a host name is created by using the files attribute. The file /etc/hostname will be created with the sl-micro1 host name:

Important
Important

Keep in mind that JSON accepts file modes in decimal numbers, for example, 420.

JSON:

{
  "ignition": {
    "version": "3.0.0"
  },
  "storage": {
    "files": [
      {
        "overwrite": true,
        "path": "/etc/hostname",
        "contents": {
          "source": "data:,sl-micro1"
        },
        "mode": 420
      }
    ]
  }
}
4.2.2.2.5 The directories attribute

The directories attribute is a list of directories that will be created in the file system. The directories attribute must contain at least one path attribute.

For example:

{
  "ignition": {
    "version": "3.0.0"
  },
  "storage": {
    "directories": [
      {
        "path": "/home/tux",
        "user": {
          "name": "tux"
        }
      }
    ]
  }
}
4.2.2.3 Users administration

The passwd attribute is used to add users. As some services, such as Cockpit, require login using a non-root user, define at least one unprivileged user here. Alternatively, you can create such a user from a running system as described in Section 6.2, “Adding users”.

To log in to your system, create root and a regular user and set their passwords. You need to hash the passwords, for example, by using the openssl command:

 openssl passwd -6

The command creates a hash of the password you chose. Use this hash as the value of the password_hash attribute.

For example:

{
  "ignition": {
    "version": "3.0.0"
  },
  "passwd": {
    "users": [
      {
        "name": "root",
        "passwordHash": "PASSWORD_HASH",
        "sshAuthorizedKeys": [
          "ssh-rsa SSH_KEY_HASH USER@HOST"
        ]
      }
    ]
  }
}

The users attribute must contain at least one name attribute. ssh_authorized_keys is a list of ssh keys for the user.

4.2.2.4 Enabling systemd services

You can enable systemd services by specifying them in the systemd attribute.

For example:

{
  "ignition": {
    "version": "3.0.0"
  },
  "systemd": {
    "units": [
      {
        "enabled": true,
        "name": "sshd.service"
      }
    ]
  }
}
4.2.2.5 Converting YAML formatted files into JSON

JSON is a universal file format for storing structured data. Applications, for example, Ignition, use it to store and retrieve their configuration. Because JSON's syntax is complex and hard to read for human beings, you can write the configuration in a more friendly format called YAML and then convert it into JSON.

4.2.2.5.1 Converting YAML files into JSON format

The tool that converts Ignition-specific vocabularies in YAML files into JSON format is butane. It also verifies the syntax of the YAML file to catch potential errors in the structure. For the latest version of butane, add the following repository:

> sudo  zypper ar -f \
  https://download.opensuse.org/repositories/devel:/kubic:/ignition/openSUSE_Tumbleweed/ \
  devel_kubic_ignition

Replace openSUSE_Tumbleweed with one of the following (depending on your distribution):

  • 'openSUSE_Leap_$releasever'

  • 15.5

Now you can install the butane tool:

> sudo  zypper ref && zypper in butane

After the installation is complete, you can invoke butane by running:

>  butane -p -o config.ign config.fcc
  • config.fcc is the path to the YAML configuration file.

  • config.ign is the path to the output JSON configuration file.

  • The -p command option adds line breaks to the output file and thus makes it more readable.

5 Deploying the raw disk image on the DASD disk

To deploy the SUSE Linux Enterprise Micro to the 20 GB DASD disk, proceed as follows:

  1. Download the raw disk image using wget or curl. For example:

    > curl -L0kO
  2. Extract the image:

    > unpack xz -d BUILD_IDENTIFICATION.raw.xz
  3. Export a variable that finds and stores the 20 GB device name.

    # export SMDASD=$(lsdasd -s | grep 20480MB | tr -s [:blank:] | cut -d' ' -f3)
  4. Format the disk:

    • If the disk is formatted for the first time:

      # dasdfmt -b 4096 -y -p /dev/$SMDASD
    • If the disk was previously formatted:

      # dasdfmt -b 4096 -M quick -y -p /dev/$SMDASD
  5. Copy the raw disk image to the disk (the device name is /dev/dasdc in our case):

    dd if=IMAGE_NAME.raw status=progress  of=/dev/dasdc bs=4k
  6. Shut down the running Linux:

    # init 0
  7. Start SUSE Linux Enterprise Micro by booting the second DASD minidisk in an x3270 terminal:

    # ipl 101

6 Post-deployment steps

6.1 Registering SLE Micro from CLI

If your system was not registered during the deployment process by using the Combustion script, you can register from the running system.

To register SUSE Linux Enterprise Micro with SUSE Customer Center, proceed as follows:

  1. Run transactional-update register as follows:

    # transactional-update register -r REGISTRATION_CODE -e EMAIL_ADDRESS

    To register with a local registration server, additionally provide the URL to the server:

    # transactional-update register -r REGISTRATION_CODE -e EMAIL_ADDRESS \
     --url "https://suse_register.example.com/"

    Replace REGISTRATION_CODE with the registration code you received with your copy of SUSE Linux Enterprise Micro. Replace EMAIL_ADDRESS with the e-mail address associated with the SUSE account you or your organization uses to manage subscriptions.

  2. Reboot your system to switch to the latest snapshot.

  3. SUSE Linux Enterprise Micro is now registered.

Note
Note: Other registration options

For information that goes beyond the scope of this section, refer to the inline documentation with SUSEConnect --help.

6.2 Adding users

As SUSE Linux Enterprise Micro requires having a non-privileged user to log in via SSH or to access Cockpit, you need to create such an account.

This step is optional if you have defined an unprivileged user in the Combustion.

  1. Run the useradd command as follows:

    # useradd -m USER_NAME
  2. Set a password for that account:

    # passwd USER_NAME
  3. If needed, add the user to the wheel group:

    # usermod -aG wheel USER_NAME