KernelCI Builder Configuration

This reposotiry contains the Ansible-based configuration for KernelCI builder VMs. They is used for building rootfs images, running bisections and run jobs in Kubernetes with dedicated credentials.

Prerequisites

First, install the Ansible tools. On Debian systems:

sudo apt install ansible

Then some necessary files are missing from this repository since they contain secrets. In order to make the Ansible commands work, those files are necessary and need to be linked in the repository. They are included in the builder-config-data encrypted repository, which only the KernelCI SysAdmin team have access to. When deploying your own instance of KernelCI, you may create a similar repository for your own use-case.

The encrypted files for main KernelCI instance are set up this way:

cd ..
git clone https://github.com/kernelci/builder-config-data.git
git-crypt unlock
cd ../builder-config2
ln -s ../builder-config-data/host_vars
ln -s ../builder-config-data/group_vars

The host names in the hosts file are defined and used only internally for the Ansible configurations. The real host names and/or their IP addresses are stored in either the group_vars/ or host_vars/ directory which are linked from the encrypted repository.

Run the Configuration

To just go through all the tasks, useful to setup a new builder:

ansible-playbook -i hosts site.yml

This assumes that you have configured the host_vars/ and group_vars/ directories with all the necessary parameters from the builder-config-data repository.

Run only some specific tasks

If you need to run only a subset of all the tasks, you can limit the ones to run using the available tags:

ansible-playbook -i hosts site.yml --tags=$TAG,$TAG

For example:

ansible-playbook -i hosts site.yml --tags=mips,mirror

Run only on some builders

If you want to run the tasks only on a subset of the builders, you can limit which one ansible will access:

ansible-playbook -i hosts site.yml -l $HOST_NAME

For example:

ansible-playbook -i hosts site.yml -l kbuilder6,kbuilder7

Other Useful Commands

To check the facts on a host:

ansible -m setup -i hosts $HOST_GROUP_NAME

Running a simple command remotely

If you need to run a simple one-time command on the managed hosts:

ansible -i hosts -m raw -a "$SHELL_COMMAND" $HOST_GROUP_NAME

For example:

ansible -i hosts -m raw -a "rm -rf /srv/mirrors" linaro
ansible -i hosts -m raw -a "rm -rf /srv/mirrors" linaro -l kbuilder6,kbuilder7

The latter is limited to kbuilder6 and kbuilder7 only.

Other examples:

ansible -i hosts -m apt -a "name=$PACKAGE_NAME" linaro # Installs a single package across all "linaro" hosts

The -m switch enables to use a single ansible module from all the available ones.

Notes

• The $HOST_GROUP_NAME name is the name given, between square brackets, in the hosts file to a group of hosts (i.e. [linaro]).