nodepool/doc/source/installation.rst
Ian Wienand 9517be8ca6 Remove statsd args to OpenStack API client call
Change If21a10c56f43a121d30aa802f2c89d31df97f121 modified nodepool to
not use the inbuilt TaskManager but use openstackapi's task handling
instead.

The statsd arguments added here don't actually do anything and are
ignored; an openstack.Connection() object doesn't setup the stats
configuration.  Things are somewhat working because of the
STATSD_<HOST|PORT> environment variables -- openstacksdk notices these
and turns on stats reporting.  However, it uses the default prefix
('openstack.api') which is a regression over the previous behaviour of
logging operations on a per-cloud basis.

I have proposed the dependent-change that will allow setting the
prefix for stats in the "metric" section of each cloud in the
openstacksdk config file.  This will allow users to return to the
previous behaviour by setting each cloud with an individual prefix in
the cloud configuration (or, indeed keep the current behaviour by not
setting that).  So along with removing the ineffective arguments, I've
updated the relevant documentation and added a release note detailing
this.

Depends-On: https://review.opendev.org/c/openstack/openstacksdk/+/786814

Change-Id: I30e57084489d822dd6152d3e5712e3cd201372ae
2021-04-20 10:19:37 +10:00

3.2 KiB

title

Installation

Installation

Nodepool consists of a long-running daemon which uses ZooKeeper for coordination with Zuul.

External Requirements

ZooKeeper

Nodepool uses ZooKeeper to coordinate image builds with its separate image builder component. A single ZooKeeper instance running on the Nodepool server is fine. Larger installations may wish to use a multi-node ZooKeeper installation, in which case three nodes are usually recommended.

Nodepool only needs to be told how to contact the ZooKeeper cluster; it will automatically populate the ZNode structure as needed.

Statsd and Graphite

If you have a Graphite system with statsd, Nodepool can be configured to send information to it. Set the environment variable STATSD_HOST to the statsd hostname (and optionally STATSD_PORT if this should be different to the default 8125) for the Nodepool daemon to enable this support.

If using the OpenStack driver, setting these variables will enable openstacksdk reporting. By default, openstacksdk will report OpenStack API statistics prefixed with openstack.api. To override this, for example to report API statistics on a per-cloud basis, see the OpenStack SDK configuration documentation on metrics.

Install Nodepool

Install Nodepool prerequisites.

Nodepool requires Python 3.6 or newer.

RHEL 7 / CentOS 7:

yum install libffi libffi-devel @development python python-devel

You may install Nodepool directly from PyPI with pip:

pip install nodepool

Or install directly from a git checkout with:

pip install .

Configuration

Nodepool has one required configuration file, which defaults to /etc/nodepool/nodepool.yaml. This can be changed with the -c option. The Nodepool configuration file is described in configuration.

There is support for a secure file that is used to store nodepool configurations that contain sensitive data. It currently only supports specifying ZooKeeper credentials and diskimage env-vars. If ZooKeeper credentials or diskimage env-vars are defined in both configuration files, the data in the secure file takes precedence. The secure file location can be changed with the -s option and follows the same file format as the Nodepool configuration file.

Warning

Secrets stored in diskimage env-vars may be leaked by the elements or in the image build logs. Before using sensitive information in env-vars, please carefully audit the elements that are enabled and ensure they are handling the environment safely.

There is an optional logging configuration file, specified with the -l option. The logging configuration file can accept either:

The Nodepool configuration file is described in configuration.