Global, Region, AZ, POD (cascaded OpenStack)
Global is a top-level logical concept in the FusionCloud solution. Only one Global can be deployed in one FusionCloud solution.
Region: a completely independent geographic region. A Region can be considered as a circle with the access latency as its radius.
Access latency
Users in a Region receive frontend services within a latency shorter than 100 ms.
Coverage area
Service quality cannot be guaranteed beyond the radius (latency). In this case, another Region is required to build new DCs for service provisioning.
Geographic redundancy
Regions are geographically diverse and allow geographical redundancy in different levels.
AZ：An available zone (AZ) is a logical zone of physical resources (computing, storage, and network resources).
The computing, storage, and network resources in an AZ are interconnected with each other. Users can bind VMs to disks and networks in the same AZ without restrictions. The cross-AZ binding is not supported.
A Region can contain multiple AZs. An AZ is included in a Region and cannot span across Regions. Multiple AZs within a Region are interconnected using high-speed optical fibers to meet requirements of building cross-AZ high-availability systems.
POD: A dedicated concept in Region Type I. One POD involves the cascaded OpenStack and all resources at the cascaded OpenStack.
Node Type
Basic management node (control node): hosts with the sys-server, controller, and measure roles deployed in the FusionSphere OpenStack system. Basic management nodes are used to deploy FusionSphere OpenStack, provide powerful virtualization functions and resource pool management capabilities, rich cloud basic service components and tools, and open and standardized APIs, helping customers horizontally integrate physical and virtual resources in DCs, and vertically optimizing service platforms.
Extended management node: indicates the FusionSphere OpenStack compute node. Extended management nodes are used to deploy cloud services and common components.
Network node: A dedicated concept in Region Type I. Network nodes are actually FusionSphere OpenStack compute nodes. A network node is a compute node with the vRouter role deployed in FusionSphere OpenStack. Network nodes are mainly used for network service deployment. Two network nodes are deployed at the network service zone of the cascading OpenStack to deploy components such as vRouter, L3NAT, L3_service, and VPN.
KVM compute node: In the FusionSphere OpenStack system, hosts that are non-management nodes and have the compute role deployed are compute nodes. The KVM compute nodes provide virtual computing functions for VMs and manage computing resources on KVM compute nodes.
