| <?xml version='1.0' encoding='utf-8' ?> |
| <!DOCTYPE section PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ |
| <!ENTITY % BOOK_ENTITIES SYSTEM "cloudstack.ent"> |
| %BOOK_ENTITIES; |
| ]> |
| |
| <!-- Licensed to the Apache Software Foundation (ASF) under one |
| or more contributor license agreements. See the NOTICE file |
| distributed with this work for additional information |
| regarding copyright ownership. The ASF licenses this file |
| to you under the Apache License, Version 2.0 (the |
| "License"); you may not use this file except in compliance |
| with the License. You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, |
| software distributed under the License is distributed on an |
| "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| KIND, either express or implied. See the License for the |
| specific language governing permissions and limitations |
| under the License. |
| --> |
| <section id="about-zones"> |
| <title>About Zones</title> |
| <para>A zone is the second largest organizational unit within a &PRODUCT; deployment. A zone |
| typically corresponds to a single datacenter, although it is permissible to have multiple |
| zones in a datacenter. The benefit of organizing infrastructure into zones is to provide |
| physical isolation and redundancy. For example, each zone can have its own power supply and |
| network uplink, and the zones can be widely separated geographically (though this is not |
| required).</para> |
| <para>A zone consists of:</para> |
| <itemizedlist> |
| <listitem><para>One or more pods. Each pod contains one or more clusters of hosts and one or more primary storage servers.</para></listitem> |
| <listitem><para>A zone may contain one or more primary storage servers, which are shared by all the pods in the zone.</para></listitem> |
| <listitem><para>Secondary storage, which is shared by all the pods in the zone.</para></listitem> |
| </itemizedlist> |
| <mediaobject> |
| <imageobject> |
| <imagedata fileref="./images/zone-overview.png" /> |
| </imageobject> |
| <textobject><phrase>zone-overview.png: Nested structure of a simple zone.</phrase></textobject> |
| </mediaobject> |
| <para>Zones are visible to the end user. When a user starts a guest VM, the user must select a zone for their guest. Users might also be required to copy their private templates to additional zones to enable creation of guest VMs using their templates in those zones.</para> |
| <para>Zones can be public or private. Public zones are visible to all users. This means that any user may create a guest in that zone. Private zones are reserved for a specific domain. Only users in that domain or its subdomains may create guests in that zone.</para> |
| <para>Hosts in the same zone are directly accessible to each other without having to go through a firewall. Hosts in different zones can access each other through statically configured VPN tunnels.</para> |
| <para>For each zone, the administrator must decide the following.</para> |
| <itemizedlist> |
| <listitem><para>How many pods to place in each zone.</para></listitem> |
| <listitem><para>How many clusters to place in each pod.</para></listitem> |
| <listitem><para>How many hosts to place in each cluster.</para></listitem> |
| <listitem><para>(Optional) How many primary storage servers to place in each zone and total capacity for these storage servers.</para></listitem> |
| <listitem><para>How many primary storage servers to place in each cluster and total capacity for these storage servers.</para></listitem> |
| <listitem><para>How much secondary storage to deploy in a zone.</para></listitem> |
| </itemizedlist> |
| <para>When you add a new zone using the &PRODUCT; UI, you will be prompted to configure the zone’s physical network |
| and add the first pod, cluster, host, primary storage, and secondary storage.</para> |
| <para>In order to support zone-wide functions for VMware, &PRODUCT; is aware of VMware Datacenters and can map each Datacenter to a |
| &PRODUCT; zone. To enable features like storage live migration and zone-wide |
| primary storage for VMware hosts, &PRODUCT; has to make sure that a zone |
| contains only a single VMware Datacenter. Therefore, when you are creating a new |
| &PRODUCT; zone, you can select a VMware Datacenter for the zone. If you |
| are provisioning multiple VMware Datacenters, each one will be set up as a single zone |
| in &PRODUCT;. </para> |
| <note> |
| <para>If you are upgrading from a previous &PRODUCT; version, and your existing |
| deployment contains a zone with clusters from multiple VMware Datacenters, that zone |
| will not be forcibly migrated to the new model. It will continue to function as |
| before. However, any new zone-wide operations, such as zone-wide primary storage |
| and live storage migration, will |
| not be available in that zone.</para> |
| </note> |
| <para/> |
| </section> |