Installing and configuring cloud-init on RHEL

Before you capture a virtual machine, you need to install the cloud-init package. This topic provides you details about cloud-init installation procedure for RHEL.

1. Perform the following steps to configure cloud-init-19.1 packages for RHEL 7.x, and RHEL 8.0. For instructions to configure RHEL provided cloud-init for RHEL 8.1 and later, see step 2.

   1. Before you install cloud-init, you must install the dependencies for cloud-init from the operating system base and supplemental media, by using yum. Ensure that the dependencies are updated to the latest level. 

      Table 1. RHEL packages

      RHEL 7.x	RHEL 8.0
      e2fsprogs iproute libselinux-python net-tools policycoreutils-python procps python(abi) = 2.7 python-configobj python-jinja2 python-jsonpatch python-oauthlib python-PrettyTable python-requests python-six python-yaml python-jsonschema	e2fsprogs iproute net-tools procps python(abi) = 3.6 python3-configobj python3-jinja2 python3-jsonpatch python3-jsonschema python3-libselinux python3-oauthlib python3-policycoreutils python3-PrettyTable python3-requests python3-six python3-yaml

   2. Obtain the latest versions of cloud-init-19.1 packages for RHEL 7.x and RHEL 8.0 from respective locations. For RHEL 7, you must install additional package dependencies before installing cloud-init packages.
   3. Run yum install download_path/<cloud-init package> to install cloud-init. Make sure you provide complete RPM path during installation.
2. To enable cloud-init on RHEL 8.1 (cloud-init-18.5-7.el8_1.4 and above), RHEL 8.2 (cloud-init-18.5-12.el8_2.6 and above) and RHEL 8.4 system, perform the following steps. Ensure the guest OS is updated to the latest version before installing cloud-init (RHEL 8.1 or RHEL 8.2 March 2021 update or above).
   1. Install the RHEL provided cloud-init.

      yum install cloud-init

   2. Add following data to /etc/cloud/cloud.cfg file. Set ssh_pwauth to false if you want to disable password authentication.

      ssh_pwauth: true
      manage_resolv_conf: false
      
      datasource_list: [ ConfigDrive, NoCloud, None ]
      datasource:
        ConfigDrive:
          dsmode: local
      

      Add resolv_conf in cloud-init module section after update_etc_hosts.

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

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

      Note: Ensure that the cloud.cfg file has the reset_rmc module listed. If you do not see the module listed, then make sure you update OS to the latest version of cloud-init.

      In case the reset_rmc module is missing even after OS update, make sure you add the module in cloud_final_modules section of the /etc/cloud/cloud.cfg as follows:

      - reset_rmc

   3. Create a new file /etc/cloud/ds-identify.cfg and add following data.

      policy: search,found=all,maybe=all,notfound=disabled

   4. Update the NetworkManager package to the latest provided by RHEL.

      yum upgrade NetworkManager

   5. Make sure firewall is configured correctly to open up RMC port 657 for inbound and outbound traffic.