nova/doc/source/user/availability-zones.rst
Stephen Finucane 5c5927a3d2 docs: Rewrite host aggregate, availability zone docs
These closely related features are the source of a disproportionate
number of bugs and a large amount of confusion among users. The spread
of information around multiple docs probably doesn't help matters.

Do what we've already done for the metadata service and remote consoles
and clean these docs up. There are a number of important changes:

- All documentation related to host aggregates and availability zones is
  placed in one of three documents, '/user/availability-zones',
  '/admin/aggregates' and '/admin/availability-zones'. (note that there
  is no '/user/aggregates' document since this is not user-facing)

- References to these features are updated to point to the new location

- A glossary is added. Currently this only contains definitions for host
  aggregates and availability zones

- nova CLI commands are replaced with their openstack CLI counterparts

- Some gaps in related documentation are closed

Change-Id: If847b0085dbfb4c813d4a8d14d99346f8252bc19
Signed-off-by: Stephen Finucane <sfinucan@redhat.com>
2019-10-07 17:26:35 +01:00

1.3 KiB

Availability zones

Availability Zones are an end-user visible logical abstraction for partitioning a cloud without knowing the physical infrastructure. Availability zones can be used to partition a cloud on arbitrary factors, such as location (country, datacenter, rack), network layout and/or power source. Because of the flexibility, the names and purposes of availability zones can vary massively between clouds.

In addition, other services, such as the networking service <> and the block storage service <>, also provide an availability zone feature. However, the implementation of these features differs vastly between these different services. Consult the documentation for these other services for more information on their implementation of this feature.

Usage

Availability zones can only be created and configured by an admin but they can be used by an end-user when creating an instance. For example:

$ openstack server create --availability-zone ZONE ... SERVER

It is also possible to specify a destination host and/or node using this command; however, this is an admin-only operation by default. For more information, see using-availability-zones-to-select-hosts.