okd/images/installer/README_INVENTORY_GENERATOR.md

Dynamic Inventory Generation

Script within the openshift-ansible image that can dynamically generate an Ansible inventory file from an existing cluster.

Configure

User configuration helps to provide additional details when creating an inventory file. The default location of this file is in /etc/inventory-generator-config.yaml. The following configuration values are either expected or default to the given values when omitted:

• master_config_path:

  • specifies where to look for the bind-mounted master-config.yaml file in the container
  • if omitted or a null value is given, its value is defaulted to /opt/app-root/src/master-config.yaml

• admin_kubeconfig_path:

  • specifies where to look for the bind-mounted admin.kubeconfig file in the container
  • if omitted or a null value is given, its value is defaulted to /opt/app-root/src/.kube/config

• ansible_ssh_user:

  • specifies the ssh user to be used by Ansible when running the specified PLAYBOOK_FILE (see README_CONTAINER_IMAGE.md for additional information on this environment variable).
  • if omitted, its value is defaulted to root

• ansible_become_user:

  • specifies a user to "become" on the remote host. Used for privilege escalation.
  • If a non-null value is specified, ansible_become is implicitly set to yes in the resulting inventory file.

See the supplied sample user configuration file in root/etc/inventory-generator-config.yaml for additional optional inventory variables that may be specified.

Build

See README_CONTAINER_IMAGE.md for information on building this image.

Run

Given a master node's master-config.yaml file, a user configuration file (see "Configure" section), and an admin.kubeconfig file, the command below will:

1. Use oc to query the host about additional node information (using the supplied kubeconfig file)
2. Generate an inventory file based on information retrieved from oc get nodes and the given master-config.yaml file.
3. run the specified openshift-ansible health.yml playbook using the generated inventory file from the previous step

docker run -u `id -u` \
       -v $HOME/.ssh/id_rsa:/opt/app-root/src/.ssh/id_rsa:Z,ro \
       -v /tmp/origin/master/admin.kubeconfig:/opt/app-root/src/.kube/config:Z \
       -v /tmp/origin/master/master-config.yaml:/opt/app-root/src/master-config.yaml:Z \
       -e OPTS="-v --become-user root" \
       -e PLAYBOOK_FILE=playbooks/openshift-checks/health.yml \
       -e GENERATE_INVENTORY=true \
       -e USER=`whoami` \
       openshift/origin-ansible

Note In the command above, specifying the GENERATE_INVENTORY environment variable will automatically generate the inventory file in an expected location. An INVENTORY_FILE variable (or any other inventory location) does not need to be supplied when generating an inventory.

Debug

To debug the generate script, run the above script interactively and manually execute /usr/local/bin/generate:

...
docker run -u `id -u` \
       -v ...
       ...
       -it openshift/origin-ansible /bin/bash

---

bash-4.2$ cd $HOME
bash-4.2$ ls
master-config.yaml
bash-4.2$ /usr/local/bin/generate $HOME/generated_hosts
bash-4.2$ ls
generated_hosts  master-config.yaml
bash-4.2$ less generated_hosts
...

Notes

See README_CONTAINER_IMAGE.md for additional information about this image.