Installation and configuration of cloud-init on the Linux server

The IBM® Cloud Infrastructure Center uses cloud-init as its activation engine. It works well with：

cloud-init 18.5 for RHEL 7.9 and RHEL 8.4
cloud-init 18.4 for SLES 15 SP1
cloud-init 19.4 for SLES 15 SP2
cloud-init 20.1 for UBUNTU 20.04
cloud-init 20.2 for SLES 15 SP3
cloud-init 21.1 for RHEL8.6, RHEL8.8 and RHEL9.0
cloud-init 22.2 for UBUNTU 22.04

If you are using a different version of cloud-init, specify the following commands as required for your version of cloud-init.

During cloud-init installation, some dependency packages might be required. You can use yum, zypper or apt-get to easily resolve these dependencies.

Follow these steps to install and configure the cloud-init service:

Installing and configuring cloud-init on RHEL
Installing and configuring cloud-init on SLES 15
Installing and configuring cloud-init on Ubuntu 20.04/Ubuntu 22.04

Installing and configuring cloud-init on RHEL

ssh to the Linux server, then run the following to install cloud-init:
```
yum install cloud-init
```
IBM Cloud Infrastructure Center uses ConfigDrive as the data source for cloud-init. Remember to disable network configure module of cloud-init because the virtual machine network is configured by zvmguestconfigure service in IBM Cloud Infrastructure Center.
- Add the following lines to the default configuration file /etc/cloud/cloud.cfg:
```
datasource_list: [ ConfigDrive, None ]
datasource:
    ConfigDrive:
        dsmode: local
network: {config: disabled}
```
- If the image is for booting a virtual machine from volume, you must disable the mounts module from the cloud-init by removing the - mounts line. When using images to boot a virtual machine from a volume, disable the mounts module in cloud-init:
  - For OS versions lower than RHEL 8.10 (RHEL7 and RHEL8.1 ~ RHEL8.9), remove the - mounts line from the cloud_config_modules section.
```
cloud_config_modules:
- locale
- mounts       <-- remove the line
- set-passwords
```
  - For OS versions RHEL 8.10 and RHEL 9, remove the - mounts line from the cloud_init_modules section.
```
cloud_init_modules:
...
- disk_setup
- mounts       <-- remove the line
- set_hostname
...
```
Note: Pay attention to the indentation, otherwise cloud-init might not work as expected.
Optionally, the default /etc/cloud/cloud.cfg file supports login by ssh key. If you want to log in by username and password via ssh, configure the /etc/cloud/cloud.cfg file:
```
ssh_pwauth: 1
```
Optionally, to enable root login, you can configure the /etc/cloud/cloud.cfg file:
```
disable_root: false
```

Enable and start the cloud-init related services by running the following commands:

systemctl enable cloud-init-local.service
systemctl start cloud-init-local.service
systemctl enable cloud-init.service
systemctl start cloud-init.service
systemctl enable cloud-config.service
systemctl start cloud-config.service
systemctl enable cloud-final.service
systemctl start cloud-final.service

If you experience problems the first time you start cloud-config.service and cloud-final.service, try to restart them.

Ensure all cloud-init services have an active status by running the following commands:

systemctl status cloud-init-local.service
systemctl status cloud-init.service
systemctl status cloud-config.service
systemctl status cloud-final.service

To verify the cloud-init configuration, issue the following command. If no errors occur, cloud-init is installed correctly:
```
cloud-init init --local
```
Remove the /var/lib/cloud directory (if it exists) so that cloud-init does not run after a restart:
```
rm -rf /var/lib/cloud
```

Installing and configuring cloud-init on SLES 15

ssh to the Linux server, then run the following to install cloud-init:
```
zypper install cloud-init    
```
Note: For SLES 15 SP1 server, the cloud-init package and required dependencies are included in the Basesystem-Module 15.1-0, Public-Cloud-Module 15.1-0 and Server-Applications-Module 15.1-0, make sure you can access these modules to install cloud-init.
IBM Cloud Infrastructure Center uses ConfigDrive as the data source for cloud-init. Remember to disable network configure module of cloud-init because the virtual machine network is configured by zvmguestconfigure service in IBM Cloud Infrastructure Center.
- Add the following lines to the default configuration file /etc/cloud/cloud.cfg:
```
datasource_list: [ ConfigDrive, None ]
datasource:
    ConfigDrive:
        dsmode: local
network: {config: disabled}
```
Note: Pay attention to the indentation, otherwise cloud-init might not work as expected.

Enable and start the cloud-init related services by running the following commands:

systemctl enable cloud-init-local.service
systemctl start cloud-init-local.service
systemctl enable cloud-init.service
systemctl start cloud-init.service
systemctl enable cloud-config.service
systemctl start cloud-config.service
systemctl enable cloud-final.service
systemctl start cloud-final.service

If you experience problems the first time you start cloud-config.service and cloud-final.service, try to restart them.

Ensure all cloud-init services have an active status by running the following commands:

systemctl status cloud-init-local.service
systemctl status cloud-init.service
systemctl status cloud-config.service
systemctl status cloud-final.service

To verify the cloud-init configuration, issue the following command. If no errors occur, cloud-init is installed correctly:
```
cloud-init init --local
```
Remove the /var/lib/cloud directory (if it exists) so that cloud-init does not run after a restart:
```
rm -rf /var/lib/cloud
```

Installing and configuring cloud-init on Ubuntu 20.04 and Ubuntu 22.04

If you do not install cloud-init during the installation, after the installation complete, ssh to the Linux server, then run the following to install cloud-init:
```
apt-get install cloud-init
```
IBM Cloud Infrastructure Center uses ConfigDrive as the data source for cloud-init. Remember to disable network configure module of cloud-init because the virtual machine network is configured by zvmguestconfigure service in IBM Cloud Infrastructure Center
- Add the following lines to the default configuration file /etc/cloud/cloud.cfg:
```
datasource_list: [ ConfigDrive, None ]
datasource:
    ConfigDrive:
        dsmode: local
network: {config: disabled}
```
Note: Pay attention to the indentation, otherwise cloud-init might not work as expected.

Optionally, when install Ubuntu, if username created same within the default_user in file /etc/cloud/cloud.cfg, set lock_passwd item value is False to enable login with password.
Check whether the file /etc/cloud/ds-identity.cfg with following content exists, if not, create this file with upcoming content.
```
policy: enabled
```
Delete file 99-installer.cfg if the file existed in path /etc/cloud/cloud.cfg.d/.

Enable and start the cloud-init related services by running the following commands:

systemctl enable cloud-init-local.service
systemctl start cloud-init-local.service
systemctl enable cloud-init.service
systemctl start cloud-init.service
systemctl enable cloud-config.service
systemctl start cloud-config.service
systemctl enable cloud-final.service
systemctl start cloud-final.service

If you experience problems the first time you start cloud-config.service and cloud-final.service, try to restart them.

Ensure all cloud-init services have an active status by running the following commands:

systemctl status cloud-init-local.service
systemctl status cloud-init.service
systemctl status cloud-config.service
systemctl status cloud-final.service

To verify the cloud-init configuration, issue the following command. If no errors occur, cloud-init is installed correctly:
```
cloud-init init --local
```
Remove the /var/lib/cloud directory (if it exists) so that cloud-init does not run after a restart:
```
rm -rf /var/lib/cloud
```