gnocchi/doc/source/install.rst
Mehdi Abaakouk 5403db73c4 ceph: make requirements clearer
This improves documentation about ceph requirements.

And this creates two new extra requirements to inform packagers
about rados libs requirements, even this is not really usefull for
our virtualenv setup.

* ceph-pre-jewel: For when Ceph version is < jewel (10.1.0)
* ceph-jewel-and-later: For when Ceph version is >= jewel

Change-Id: I75bb096d8ede2e1e0076d22eaeac5eabc1c03ded
2016-04-04 13:07:07 +02:00

3.6 KiB
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Installation

Installation Using Devstack

To enable Gnocchi in devstack, add the following to local.conf:

enable_plugin gnocchi https://github.com/openstack/gnocchi master
enable_service gnocchi-api,gnocchi-metricd

To enable Grafana support in devstack, you can also enable `gnocchi-grafana`:

enable_service gnocchi-grafana

Then, you can start devstack:

./stack.sh

Installation

To install Gnocchi using pip, just type:

pip install gnocchi

Depending on the drivers and features you want to use, you need to install extra variants using, for example:

pip install gnocchi[postgresql,ceph,keystone]

This would install PostgreSQL support for the indexer, Ceph support for storage, and Keystone support for authentication and authorization.

The list of variants available is:

  • keystone provides Keystone authentication support
  • mysql - provides MySQL indexer support
  • postgresql provides PostgreSQL indexer support
  • swift provides OpenStack Swift storage support
  • ceph provides common part of Ceph storage support
  • ceph-pre-jewel provides Ceph (<10.1.0) storage support
  • ceph-jewel-and-later provides Ceph (>=10.1.0) storage support
  • file provides file driver support
  • doc documentation building support
  • test unit and functional tests support

To install Gnocchi from source, run the standard Python installation procedure:

pip install -e .

Again, depending on the drivers and features you want to use, you need to install extra variants using, for example:

pip install -e .[postgresql,ceph,ceph-pre-jewel]

Ceph requirements

Gnocchi leverages omap API of librados, but this is available in python binding only since python-rados >= 9.1.0. To handle this, Gnocchi uses 'cradox' python library which has exactly the same API but works with Ceph >= 0.80.0.

If Ceph and python-rados are >= 9.1.0, cradox python library becomes optional but is still recommended until 10.1.0.

Initialization

Once you have configured Gnocchi properly (see configuration), you need to initialize the indexer and storage:

gnocchi-upgrade

Upgrading

In order to upgrade from a previous version of Gnocchi, you need to make sure that your indexer and storage are properly upgraded. Run the following:

  1. Stop the old version of Gnocchi API server and metric daemon
  2. Install the new version of Gnocchi
  3. Run gnocchi-upgrade This can take several hours depending on the size of your index and storage.
  4. Start the new Gnocchi API server and metric daemon

Minimal interruption upgrade

Gnocchi supports online upgrade of its storage system, which avoids interrupting Gnocchi for a long time. In order to upgrade from previous versions, you need to follow the following steps:

  1. Stop the old Gnocchi API server and metric daemon
  2. Run gnocchi-upgrade --skip-storage with the new version of Gnocchi. This can take several minutes depending on the size of your index.
  3. Start the new Gnocchi API server.
  4. Run gnocchi-upgrade with the new version of Gnocchi This can take several hours depending on the size of your storage.
  5. Start the new Gnocchi metric daemon.

This will upgrade the indexer and storage in two passes. While a new version of Gnocchi API cannot run with an old version of the indexer, it can run with an old version of its storage back-end. For performance reasons, _metricd needs to run an upgraded storage back-end, otherwise it would spend too much time checking for upgrade pattern on each run.