bifrost/README.rst
2015-08-19 18:22:53 +00:00

16 KiB

Bifrost

Bifrost is a set of Ansible playbooks that automates the task of deploying a base image onto a set of known hardware using Ironic. It provides modular utility for one-off operating system deployment with as few operational requirements as reasonably possible.

This is split into roughly three steps:

  • install: prepare the local environment by downloading and/or building machine images, and installing and configuring the necessary services.
  • enroll-dynamic: take as input a customizable hardware inventory file and enroll the listed hardware with Ironic, configuring each appropriately for deployment with the previously-downloaded images.
  • deploy-dynamic: instruct Ironic to deploy the operating system onto each machine.

Supported Operating Systems:

  • Ubuntu 14.04, 14.10
  • Red Hat Enterprise Linux (RHEL) 7
  • CentOS 7

Pre-install steps

Installing bifrost on RHEL or CentOS requires a few extra pre-install steps.

Enable additional repositories (RHEL only)

The extras and optional yum repositories must be enabled to satisfy bifrost's dependencies. To check:

sudo yum repolist | grep 'optional\|extras'

To add the repositories:

sudo yum repolist all | grep 'optional\|extras'

The output will look like this:

!rhui-REGION-rhel-server-debug-extras/7Server/x86_64        Red H disabled
rhui-REGION-rhel-server-debug-optional/7Server/x86_64       Red H disabled
rhui-REGION-rhel-server-extras/7Server/x86_64               Red H disabled
rhui-REGION-rhel-server-optional/7Server/x86_64             Red H disabled
rhui-REGION-rhel-server-source-extras/7Server/x86_64        Red H disabled
rhui-REGION-rhel-server-source-optional/7Server/x86_64      Red H disabled

Use the names of the repositories (minus the version and architecture) to enable them:

sudo yum-config-manager --enable rhui-REGION-rhel-server-optional
sudo yum-config-manager --enable rhui-REGION-rhel-server-extras

Enable the EPEL repository (RHEL)

The Extra Packages for Enterprise Linux (EPEL) repository contains some of bifrost's dependencies. To enable it, install the epel-release package as follows:

sudo yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm

Enable the EPEL repository (CentOS)

To enable EPEL on CentOS, run:

sudo yum install epel-release

Installation

The installation is split into two parts.

The first part is a bash script which lays the basic groundwork of installing Ansible itself.

Edit ./playbooks/inventory/group_vars/* to match your environment. The localhost file is intended for steps executed upon the localhost, such as installation, or image generation. The baremetal file is geared for steps performed on baremetal nodes, such as enrollment, deployment, or any other custom playbooks that a user may bolt on to this toolkit.

  • If MySQL is already installed, update mysql_password to match your local installation.
  • Change network_interface to match the interface that will need to service DHCP requests.
  • Change the ironic_db_password which is set by Ansible in MySQL and in Ironic's configuration file.

The install process builds or modifies a disk image to deploy. The following two settings (which are mutually exclusive) allow you to choose if a partition image is used or an image is created with diskimage-builder.

create_image_via_dib: true transform_boot_image: false

Proxy:

if running behind the proxy. export environment variables http_proxy and https_proxy So that ansible lookup plugin checks for proxy set and uses as environment variables.

Then run:

bash ./scripts/env-setup.sh
source /opt/stack/ansible/hacking/env-setup
cd playbooks

The second part is an Ansible playbook that installs and configures Ironic in a stand-alone fashion.

  • Keystone is NOT installed, and Ironic's API is accessible without authentication. It is possible to put basic password auth on Ironic's API by changing the nginx configuration accordingly.
  • Neutron is NOT installed. Ironic performs static IP injection via config-drive.
  • dnsmasq is configured statically and responds to all PXE boot requests by chain-loading to iPXE, which then fetches the ironic-python-agent ramdisk from Nginx.
  • Deployments are performed by the Ironic Python Agent, which as configured supports IPMI, iLO, and UCS drivers. AMT driver support is also enabled, however it should only be use for testing as due to a known bug which can be read about at https://bugs.launchpad.net/ironic/+bug/1454492.
  • By default, installation will build an Ubuntu based image for deployment to nodes. This image can be easily customized if so desired.

The re-execution of the playbook will cause states to be re-asserted. If not already present, a number of software packages including MySQL and RabbitMQ will be installed on the host. Python code will be re-installed regardless if it has changed, RabbitMQ user passwords will be reset, and services will be restarted.

Run:

If you have password-less sudo enabled, run:
   ansible-playbook -vvvv -i inventory/localhost install.yaml
Otherwise, add -K option to let Ansible prompting for the sudo  password:
   ansible-playbook -K -vvvv -i inventory/localhost install.yaml

With regards to testing, ironic's node cleaning capability is disabled by default as it can be an unexpected surprise for a new user that their test node is unusable for however long it takes for the disks to be wiped.

If you wish to enable cleaning, you can achieve this by passing the option "-e cleaning=true" to the command line or executing the command below.:

ansible-playbook -K -vvvv -i inventory/localhost install.yaml -e cleaning=true

After you have performed an installation, you can edit /etc/ironic/ironic.conf to enable or disable cleaning as desired, however it is highly encouraged to utilize cleaning in any production environment.

Manual CLI Use

If you wish to utilize Ironic's CLI in no-auth mode, you must set two environment variables:

  • IRONIC_URL - A URL to the Ironic API, such as http://localhost:6385/
  • OS_AUTH_TOKEN - Any value, such as an empty space, is required to cause the client library to send requests directly to the API.

For your ease of use, env-vars can be sourced to allow the CLI to connect to a local Ironic installation operating in noauth mode.

Hardware Enrollment

The following requirements are installed during the Install step above:

  • openstack-infra/shade library
  • openstack-infra/os-client-config

In order to enroll hardware, you will naturally need an inventory of your hardware. When utilizing the dynamic inventory module and accompanying roles this can be supplied in one of three ways, all of which ultimately translate to JSON data that Ansible parses.

The original method is to utilize a CSV file. This format is covered below in the Legacy CSV File Format section. This has a number of limitations, but does allow a user to bulk load hardware from an inventory list with minimal data transformations.

The newer method is to utilize a JSON or YAML document which the inventory parser will convert and provide to Ansible.

In order to use, you will need to define the environment variable BIFROST_INVENTORY_SOURCE to equal a file, which then allows you to execute Ansible utilizing the bifrost_inventory.py file as the data source.

Conversion from CSV to JSON formats

The inventory/bifrost_inventory.py program additionally features a mode that allows a user to convert a CSV file to the JSON data format utilizing a --convertcsv command line setting when directly invoked.

Example:

export BIFROST_INVENTORY_SOURCE=/tmp/baremetal.csv
inventory/bifrost_inventory.py --convertcsv >/tmp/baremetal.json

JSON file format

The JSON format closely resembles the data structure that Ironic utilizes internally. The name, driver_info, nics, driver, and properties fields are directly mapped through to Ironic. This means that the data contained within can vary from host to host, such as drivers and their parameters thus allowing a mixed hardware environment to be defined in a single file.

Example:

{
    "testvm1": {
      "uuid": "00000000-0000-0000-0000-000000000001",
      "driver_info": {
        "power": {
          "ssh_port": 22,
          "ssh_username": "ironic",
          "ssh_virt_type": "virsh",
          "ssh_address": "192.168.122.1",
          "ssh_key_filename": "/home/ironic/.ssh/id_rsa"
        }
      },
      "nics": [
        {
          "mac": "52:54:00:f9:32:f6"
        }
      ],
      "driver": "agent_ssh",
      "ansible_ssh_host": "192.168.122.2",
      "ipv4_address": "192.168.122.2",
      "properties": {
        "cpu_arch": "x86_64",
        "ram": "3072",
        "disk_size": "10",
        "cpus": "1"
      },
      "name": "testvm1"
    }
}

The additional power of this format is easy configuration parameter injection, which could potentially allow a user to provision different operating system images onto different hardware chassis by defining the appropriate settings in an "instance_info" variable.

Examples utilizing JSON and YAML formatting, along host specific variable injection can be found in the playbooks/inventory/ folder.

Legacy CSV File Format

The CSV file has the following columns:

  1. MAC Address
  2. Management username
  3. Management password
  4. Management Address
  5. CPU Count
  6. Memory size in MB
  7. Disk Storage in GB
  8. Flavor (Not Used)
  9. Type (Not Used)
  10. Host UUID
  11. Host or Node name
  12. Host IP Address to be set
  13. ipmi_target_channel - Requires: ipmi_bridging set to single
  14. ipmi_target_address - Requires: ipmi_bridging set to single
  15. ipmi_transit_channel - Requires: ipmi_bridging set to dual
  16. ipmi_transit_address - Requires: ipmi_bridging set to dual
  17. ironic driver

Example definition:

00:11:22:33:44:55,root,undefined,192.168.122.1,1,8192,512,NA,NA,aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee,hostname_100,192.168.2.100,,,,agent_ipmitool

This file format is fairly flexible and can be easily modified although the enrollment and deployment playbooks utilize the model of a host per line model in order to process through the entire list, as well as reference the specific field items.

An example file can be found at: playbooks/inventory/baremetal.csv.example

How this works?

Utilizing the dynamic inventory module, enrollment is as simple as setting the BIFROST_INVENTORY_SOURCE environment variable to your inventory data source, and then executing the enrollment playbook.:

export BIFROST_INVENTORY_SOURCE=/tmp/baremetal.json
ansible-playbook -vvvv -i inventory/bifrost_inventory.py enroll-dynamic.yaml

Note that enrollment is a one-time operation. The Ansible module does not synchronize data for existing nodes. You should use the Ironic CLI to do this manually at the moment.

Additionally, it is important to note that the playbooks for enrollment are split into three separate playbooks based up the setting of ipmi_bridging.

Hardware Deployment

How this works?

After the nodes are enrolled, they can be deployed upon. Bifrost is geared to utilize configuration drives to convey basic configuration information to the each host. This configuration information includes an SSH key to allow a user to login to the system.

To utilize the newer dynamic inventory based deployment:

export BIFROST_INVENTORY_SOURCE=/tmp/baremetal.json
ansible-playbook -vvvv -i inventory/bifrost_inventory.py deploy-dynamic.yaml

Testing with a single command

A simple scripts/test-bifrost.sh script can be utilized to install pre-requisite software packages, Ansible, and then execute the test-bifrost.yaml playbook in order to provide a single step testing mechanism.

The playbook utilized by the script, playbooks/test-bifrost-dynamic.yaml, is a single playbook that will create a local virtual machine, save a baremetal.csv file out, and then utilize it to execute the remaining roles. Two additional roles are invoked by this playbook which enables Ansible to connect to the new nodes by adding them to the inventory, and then logging into the remote machine via the user's ssh host key. Once that has successfully occurred, additional roles will unprovision the host(s) and delete them from Ironic.

Command:

scripts/test-bifrost.sh

Note:

  • Cleaning mode is explicitly disabled in the test-bifrost.yaml playbook due to the fact that is an IO intensive operation that can take a great deal of time.

Legacy - Testing with Virtual Machines

Bifrost supports using virtual machines to emulate the hardware. All of the steps mentioned above are mostly the same.

It is assumed you have an SSH server running on the host machine. The agent_ssh driver, used by Ironic with VM testing, will need to use SSH to control the virtual machines.

An SSH key is generated for the ironic user when testing. The ironic conductor will use this key to connect to the host machine and run virsh commands.

  1. Set testing to true in the playbooks/inventory/group_vars/localhost file.
  2. You may need to adjust the value for ssh_public_key_path.
  3. Run the install step, as documented above, however adding "-e testing=true" to the Ansible command line.
  4. Execute the ansible-playbook -vvvv -i inventory/localhost test-bifrost-create-vm.yaml command to create a test virtual machine.
  5. Set the environment variable of BIFROST_INVENTORY_SOURCE to the path to the csv file, which by default has been written to /tmp/baremetal.csv.
  6. Run the enrollment step, as documented above, using the CSV file you created in the previous step.
  7. Run the deployment step, as documented above.

Deployment and configuration of Operating Systems

By default, Bifrost deploys a configuration drive which includes the user SSH public key, hostname, and the network configuration in the form of network_info.json that can be read/parsed by the glean <https://github.com/openstack-infra/glean> utility. This allows for the deployment of Ubuntu, CentOS, Fedora "tenants" on baremetal. This file format is not yet supported by Cloud-Init, however it is on track for inclusion in cloud-init 2.0.

By default, Bifrost utilizes a utility called simple-init which leverages the previously noted glean utility to apply network configuration. This means that by default, root file systems may not be automatically expanded to consume the entire disk, which may, or may not be desirable depending upon operational needs. This is dependent upon what base OS image you utilize, and if the support is included in that image or not. At present, the standard ubuntu cloud image includes cloud-init which will grow the root partition, however the ubuntu-minimal image does not include cloud-init and thus will not automatically grow the root partition.

Due to the nature of the design, it would be relatively easy for a user to import automatic growth or reconfiguration steps either in the image to be deployed, or in post-deployment steps via custom Ansible playbooks.

Custom IPA Images

Bifrost supports the ability for a user to build a custom IPA ramdisk utilizing the diskimage-builder element "ironic-agent". In order to utilize this feature, the download_ipa setting must be set to "false" and the create_ipa_image must be set to "true". By default, the playbook will build a Debian based IPA image, if a pre-existing IPA image is not present on disk.

If you wish to include an extra element into the IPA disk image, such as a custom hardware manager, you can pass the variable "ipa_extra_dib_elements" as a space separated list of elements. This defaults to an emtpy string.