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Sparse allocation evenly distributes assignments throughout an IPv6 range, using either a manually configured or automatically generated "Sparse Allocate" Numbering Authority domain algorithm to calculate the next block to assign.
Sparse Allocation Schemes
Admins may select a system default Sparse Allocation scheme to use for IPv6 Sparse Allocation. Available values are Leftmost, Center, and Rightmost. If not otherwise specified, Leftmost is the ProVision Default.
To edit the Sparse Allocation Scheme, select the desired scheme in IPAM Configuration, then enable sparse allocation for the desired IPv6 aggregate. The Sparse allocation scheme is applied to the aggregate when sparse allocation is enabled for the aggregate, thus, pre-existing sparse allocation schemes will not be altered by later changes.
If you wish to change the scheme for an existing sparse allocated-enabled aggregate, you must
1) Disable sparse allocation for the aggregate → 2) Edit the selected scheme → 3) re-enable sparse allocate for the aggregate.
To verify which scheme is applied to aggregates, you may view the aggregate and scheme details in the Numbering Authority → Sparse Allocate listings.
Enable/Disable Sparse Allocation
Sparse allocation options are accessed from the IPv6 Aggregate's Action Menu (gear icon). The top right corner of the Utilization module for the IPv6 aggregate will display whether sparse allocation is enabled or disabled for the particular aggregate.
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Enable or disable Sparse Allocation for the aggregate by clicking on the aggregate menu, and select to Enable / Disable Sparse Allocation for the aggregate. A "Sparse Allocate" Numbering Domain will automatically be generated for the aggregate in the Admin → IPAM Admin area of ProVision, using the currently set Sparse Allocation Scheme setting.
Once enabled, the "Sparse Allocate" option will be available for the aggregate.
Sparse Allocate
To Sparse Allocate assign the next IP generated, select "Sparse Allocate" from the aggregate action menu.
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