diff --git a/docs/en-US/about-clusters.xml b/docs/en-US/about-clusters.xml index e328cbaa169..a39cf716168 100644 --- a/docs/en-US/about-clusters.xml +++ b/docs/en-US/about-clusters.xml @@ -24,9 +24,25 @@
About Clusters - A cluster provides a way to group hosts. To be precise, a cluster is a XenServer server pool, a set of KVM servers, a set of OVM hosts, or a VMware cluster preconfigured in vCenter. The hosts in a cluster all have identical hardware, run the same hypervisor, are on the same subnet, and access the same shared primary storage. Virtual machine instances (VMs) can be live-migrated from one host to another within the same cluster, without interrupting service to the user. - A cluster is the third-largest organizational unit within a &PRODUCT; deployment. Clusters are contained within pods, and pods are contained within zones. Size of the cluster is limited by the underlying hypervisor, although the &PRODUCT; recommends less in most cases; see Best Practices. - A cluster consists of one or more hosts and one or more primary storage servers. + + A cluster provides a way to group hosts. To be precise, a cluster is a + XenServer server pool, a set of KVM servers, a set of OVM hosts, or a + VMware cluster preconfigured in vCenter. The hosts in a cluster all + have identical hardware, run the same hypervisor, are on the same subnet, + and access the same shared primary storage. Virtual machine instances + (VMs) can be live-migrated from one host to another within the same + cluster, without interrupting service to the user. + + + A cluster is the third-largest organizational unit within a &PRODUCT; + deployment. Clusters are contained within pods, and pods are contained + within zones. Size of the cluster is limited by the underlying hypervisor, + although the &PRODUCT; recommends less in most cases; see Best Practices. + + + A cluster consists of one or more hosts and one or more primary storage + servers. + @@ -34,6 +50,14 @@ cluster-overview.png: Structure of a simple cluster &PRODUCT; allows multiple clusters in a cloud deployment. - Even when local storage is used, clusters are still required. In this case, there is just one host per cluster. - When VMware is used, every VMware cluster is managed by a vCenter server. Administrator must register the vCenter server with &PRODUCT;. There may be multiple vCenter servers per zone. Each vCenter server may manage multiple VMware clusters. + + Even when local storage is used exclusively, clusters are still required + organizationally, even if there is just one host per cluster. + + + When VMware is used, every VMware cluster is managed by a vCenter server. + Administrator must register the vCenter server with &PRODUCT;. There may + be multiple vCenter servers per zone. Each vCenter server may manage + multiple VMware clusters. +