system-config/doc/source/systems.rst

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Infrastructure Systems

Infrastructure Systems

The OpenStack Infrastructure team maintains a number of systems that are critical to the operation of the OpenStack project, such as gerrit, jenkins, mailman, meetbot, etherpad, paste, and others.

Additionally the team maintains the project sites on Launchpad and GitHub. The following policies have been adopted to ensure the continued and secure operation of the project.

SSH Access

For any of the systems managed by the OpenStack Infrastructure team, the following practices must be observed for SSH access:

  • SSH access is only permitted with SSH public/private key authentication.
  • Users must use a strong passphrase to protect their private key. A passphrase of several words, at least one of which is not in a dictionary is advised, or a random string of at least 16 characters.
  • To mitigate the inconvenience of using a long passphrase, users may want to use an SSH agent so that the passphrase is only requested once per desktop session.
  • Users private keys must never be stored anywhere except their own workstation(s). In particular, they must never be stored on any remote server.
  • If users need to 'hop' from a server or bastion host to another machine, they must not copy a private key to the intermediate machine (see above). Instead SSH agent forwarding may be used. However due to the potential for a compromised intermediate machine to ask the agent to sign requests without the users knowledge, in this case only an SSH agent that interactively prompts the user each time a signing request (ie, ssh-agent, but not gnome-keyring) is received should be used, and the SSH keys should be added with the confirmation constraint ('ssh-add -c').
  • The number of SSH keys that are configured to permit access to OpenStack machines should be kept to a minimum.
  • OpenStack Infrastructure machines must use puppet to centrally manage and configure user accounts, and the SSH authorized_keys files from the openstack-infra/config repository.
  • SSH keys should be periodically rotated (at least once per year). During rotation, a new key can be added to puppet for a time, and then the old one removed. Be sure to run puppet on the backup servers to make sure they are updated.

Servers

Because the configuration of servers is managed in puppet, anyone may propose changes to existing servers, or propose that new servers be created by editing the puppet configuration and uploading a change for review in Gerrit. The installation and maintenance of software on project infrastructure servers should be carried out entirely through puppet so that anyone can contribute.

The Git repository with the puppet configuration may be cloned from https://github.com/openstack-infra/config and changes submitted with git-review.

In order to ensure that it is easy for both the OpenStack project as well as others to re-use the configuration in that repository, server definitions are split into two levels of abstraction: first, a class is created that defines the configuration of the server, but without specifics such as hostnames and passwords. Then a node definition is created that uses that class, passing in any specific information needed for that node.

For instance, modules/openstack_project/manifests/gerrit.pp defines a class which specifies how the OpenStack project configures a gerrit server, and then manifests/site.pp defines a node that uses that class, passing in passwords and other information specific to that node obtained from puppet's hiera.

To create a new server, do the following:

  • Add a file in modules/openstack_project/manifests/ that defines a class which specifies the configuration of the server.

  • Add a node entry in manifests/site.pp for the server that uses that class.

  • If your server needs private information such as password,s use hiera calls in the site manifest, and ask an infra-core team member to manually add the private information to hiera.

  • You should be able to install and configure most software only with puppet. Nonetheless, if you need SSH access to the host, add your public key to modules/openstack_project/manifests/users.pp and include a stanza like this in your server class:

    realize (
       User::Virtual::Localuser['USERNAME'],
    )
  • Add an RST file with documentation about the server in doc/source and add it to the index in that directory.

Backups

Off-site backups are made to two servers:

  • ci-backup-rs-ord.openstack.org
  • ci-backup-hp-az1.openstack.org

Puppet is used to perform the initial configuration of those machines, but to protect them from unauthorized access in case access to the puppet git repo is compromised, it is not run in agent or in cron mode on them. Instead, it should be manually run when changes are made that should be applied to the backup servers.

To start backing up a server, some commands need to be run manually on both the backup server, and the server to be backed up. On the server to be backed up:

ssh-keygen -t rsa -f /root/.ssh/id_rsa -N ""

And then ''cat /root/.ssh/id_rsa.pub'' for use later.

On the backup servers:

sudo su -
BUPUSER=bup-<short-servername>  # eg, bup-jenkins-dev
useradd -r $BUPUSER -s /bin/bash -m
cd /home/$BUPUSER
mkdir .ssh
cat >.ssh/authorized_keys

and add this to the authorized_keys file:

command="BUP_DEBUG=0 BUP_FORCE_TTY=3 bup server",no-port-forwarding,no-agent-forwarding,no-X11-forwarding,no-pty <ssh key from earlier>

Switching back to the server to be backed up, run:

ssh $BUPUSER@ci-backup-rs-ord.openstack.org
ssh $BUPUSER@ci-backup-hp-az1.openstack.org

And verify the host key. Add the "backup" class in puppet to the server to be backed up.

GitHub Access

To ensure that code review and testing are not bypassed in the public Git repositories, only Gerrit will be permitted to commit code to OpenStack repositories. Because GitHub always allows project administrators to commit code, accounts that have access to manage the GitHub projects necessarily will have commit access to the repositories. Therefore, to avoid inadvertent commits to the public repositories, unique administrative-only accounts must be used to manage the OpenStack GitHub organization and projects. These accounts will not be used to check out or commit code for any project.

Launchpad Teams

Each OpenStack project should have the following teams on Launchpad:

  • foo -- contributors to project 'foo'
  • foo-core -- core developers
  • foo-bugs -- people interested in receieving bug reports
  • foo-drivers -- people who may approve and target blueprints

The openstack-admins team should be a member of each of those teams.