Availability Zones are defined to aid fault tolerance. This enables you to arrange OpenStack compute hosts into logical groups and provides a form of physical isolation and redundancy from other availability zones, such as by using a separate power supply or network equipment.
The Availability Zones tab under Cloud OpenStack displays information for all availability zones for the selected cloud. You can access the Availability Zones tab in one of the following ways:
This tab contains the Availability Zones table that displays the following information for each availability zone in the selected cloud:
Availability Zones table: Description of columns
|Name||Hyperlinked name of the host aggregate in the Availability Zone. For more information, see Host Aggregates.||Last Value||NAME|
|CPU Capacity [GHz]||Total CPU capacity available in the selected zone, measured in GHz.||Last Value||TOTAL_CPU_MHZ|
|CPU Used [GHz]||Total CPU used by all the host aggregates in the selected zone, measured in GHz.||95th percentile|
|CPU Utilization [%]||Percentage of total CPU utilized by the selected zone.||95th percentile||CPU_UTIL|
|CPU Trend [%]||The daily growth rate of CPU utilization of the zone.||Trend||Trend based on CPU_UTIL|
|Memory Capacity [GB]||Total physical memory capacity in the selected zone, measured in GB.||Last value||TOTAL_REAL_MEM|
|Memory Used [GB]||Total physical memory used by the host aggregates in the selected zone, measured in GB.||95th percentile|
|Memory Utilization [%]||Percentage of total physical memory utilized by the host aggregates in the selected zone.||95th percentile||MEM_UTIL|
|Memory Trend [%]||Daily growth rate of memory utilization of the zone.||Trend||Trend based on MEM_UTIL|
|Ephemeral Storage Size [GB]||Total capacity of ephemeral storage, measured in GB.||Last value||TOTAL_EPHEMERAL_DISK_SIZE|
|Ephemeral Provisioned Storage [GB]||Total ephemeral storage provisioned to the virtual machines in OpenStack measured in GB.||95th percentile||TOTAL_EPHEMERAL_DISK_PROVISIONED|
|Datastore Capacity [GB]||Total capacity of the datastore, measured in GB.||Last value||TOTAL_DSTORE_SIZE|
|Datastore Used [GB]||Total used space in the datastore, measured in GB.||95th percentile|
|Datastore Utilization [%]||Percentage of total datastore capacity used by the host aggregates in the selected zone.||95th percentile|
|Datastore Trend [%]||Daily growth rate of datastore utilization of the zone.||Trend||Trend based on DSTORE_UTIL|
|CPU Overcommit Ratio|
Ratio of vCPUs allocated to the virtual machines to total physical CPUs available in the hypervisors in the Availability Zone.
|Computed based on last values||VCPU_ON_NUM, CPU_NUM|
|Memory Overcommit Ratio|
Ratio of memory allocated to the VMs to the total physical memory available in the hypervisors in the Availability Zone.
|Computed based on last values||SUM (VM.TOTAL_REAL_MEM), TOTAL_REAL_MEM|
|Ephemeral Storage Overcommit Ratio||Ratio of ephemeral storage provisioned to the total capacity of ephemeral storage.||Computed metric||TOTAL_EPHEMERAL_DISK_SIZE, TOTAL_EPHEMERAL_DISK_PROVISIONED|
|Hypervisor Count||The number of hypervisors on the host aggregate for a selected zone.||Last value||HOST_NUM|
|Powered On VMs||Number of virtual machines that are powered on.||95th percentile||GM_ON_NUM|
|Spare VMs||Estimated number of additional virtual machines that can be placed in the host aggregate, calculated based on the remaining CPU, Memory and Storage capacity. For more information, see Spare VM calculation in Recalculating the spare VM basis.||Computed by AFS using total capacity and 95th utilization of CPU, Memory and Storage||IND_SPARE_VM|
|Spare VM Basis|
Specifies the basis for calculating the number of additional VMs that can be placed in the Zone: TYPICAL or CUSTOM.
For more information, see Spare VM calculation in !in Recalculating the spare VM basis.
|NA||TYPICAL or CUSTOM|
|Days to Saturation||The projected amount of time before one of the resources (CPU, MEMORY, STORAGE) in the Zone runs out of available capacity. Number of days to saturation for the least available resource is reported here.|
Computed by AFS using total capacity and 95th utilization of CPU, Memory and Storage
|Bottleneck Resource||Name of the resource that has either saturated or will saturate in the next 30 days. Bottleneck resource can be CPU, MEMORY or STORAGE. The field is blank if none of the resources has saturated, or will saturate.||Computed by AFS using total capacity and 95th utilization of CPU, Memory and Storage||IND_BNECK_RESOURCE|