openstack-ansible/doc/source/developer-docs/installation-hosts-limited-connectivity.rst

Installation on hosts with limited connectivity

Many playbooks and roles in OpenStack-Ansible retrieve dependencies from the public Internet by default. Many deployers block direct outbound connectivity to the Internet when implementing network security measures. We recommend a set of practices and configuration overrides deployers can use when running OpenStack-Ansible in network environments that block Internet connectivity.

The options below are not mutually exclusive and may be combined if desired.

Example internet dependencies

• Software packages
• LXC container images
• Source code repositories
• GPG keys for package validation

Install pip through deployment host

You may install pip via the deployment host in environments where the deployment host has internet connectivity, but the containers do not.

Configure the pip_offline_install variable to enable the deployment host to fetch pip along with its dependencies, then transfer them to the remote container for installation.

Configuration changes are made in /etc/openstack_deploy/user_variables.yml.

# Install pip via deployment host
pip_offline_install: true

Practice A: Mirror internet resources locally

You may choose to operate and maintain mirrors of OpenStack-Ansible and OpenStack dependencies. Mirrors often provide a great deal of risk mitigation by reducing dependencies on resources and systems outside of your direct control. Mirrors can also provide greater stability, performance and security.

Software package repositories

Many packages used to run OpenStack are installed using pip. We advise mirroring the PyPi package index used by pip.

Many software packages are installed on the target hosts using .deb packages. We advise mirroring the repositories that host these packages.

Ubuntu repositories to mirror:

• trusty
• trusty-updates
• trusty-backports

Galera-related repositories to mirror:

• https://mirror.rackspace.com/mariadb/repo/10.0/ubuntu
• https://repo.percona.com/apt

These lists are intentionally not exhaustive. Consult the OpenStack-Ansible playbooks and role documentation for further repositories and the variables that may be used to override the repository location.

LXC container images

OpenStack-Ansible relies upon community built LXC images when building containers for OpenStack services. Deployers may choose to create, maintain, and host their own container images. Consult the openstack-ansible-lxc_container_create role for details on configuration overrides for this scenario.

Source code repositories

OpenStack-Ansible relies upon Ansible Galaxy to download Ansible roles when bootstrapping a deployment host. Deployers may wish to mirror the dependencies that are downloaded by the bootstrap-ansible.sh script.

Deployers can configure the script to source Ansible from an alternate Git repository by setting the environment variable ANSIBLE_GIT_REPO.

Deployers can configure the script to source Ansible role dependencies from alternate locations by providing a custom role requirements file and specifying the path to that file using the environment variable ANSIBLE_ROLE_FILE.

Practice B: Proxy access to internet resources

Configure target and deployment hosts to reach public internet resources via HTTP or SOCKS proxy server(s). OpenStack-Ansible may be used to configure target hosts to use the proxy server(s). OpenStack-Ansible does not provide automation for creating the proxy server(s).

Note

We recommend you set your /etc/environment variables with proxy settings before launching scripts/run-playbooks.sh to avoid failure.

Basic proxy configuration

The following configuration configures most network clients on the target hosts to connect via the specified proxy. For example, these settings affect:

• Most Python network modules
• curl
• wget
• openstack

Use the no_proxy environment variable to specify hosts that you cannot reach through the proxy. These often are the hosts in the management network. In the example below, no_proxy is set to localhost only, but the default configuration file suggests using variables to list all the hosts/containers' management addresses as well as the load balancer internal/external addresses.

Configuration changes are made in /etc/openstack_deploy/user_variables.yml.

# Used to populate /etc/environment
global_environment_variables:
   HTTP_PROXY: "http://proxy.example.com:3128"
   HTTPS_PROXY: "http://proxy.example.com:3128"
   NO_PROXY: "localhost,127.0.0.1"
   http_proxy: "http://proxy.example.com:3128"
   https_proxy: "http://proxy.example.com:3128"
   no_proxy: "localhost,127.0.0.1"

apt-get proxy configuration

See Setting up apt-get to use a http-proxy

Deployment host proxy configuration for bootstrapping Ansible

Configure the bootstrap-ansible.sh script used to install Ansible and Ansible role dependencies on the deployment host to use a proxy by setting the environment variables HTTPS_PROXY or HTTP_PROXY.

Considerations when proxying TLS traffic

Proxying TLS traffic often interferes with the clients ability to perform successful validation of the certificate chain. Various configuration variables exist within the OpenStack-Ansible playbooks and roles that allow a deployer to ignore these validation failures. Find an example /etc/openstack_deploy/user_variables.yml configuration below:

pip_validate_certs: false
galera_package_download_validate_certs: false

The list above is intentionally not exhaustive. Additional variables may exist within the project and will be named using the *_validate_certs pattern. Disable certificate chain validation on a case by case basis and only after encountering failures that are known to only be caused by the proxy server(s).

Ansible support for proxy servers

The get_url and uri modules in Ansible 1.9.x have inconsistent and buggy behavior when used in concert with many popular proxy servers and configurations. An example Launchpad bug can be found here. The comments contain a workaround that has been effective for some deployers.

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