When you create certain objects through BloxOne Universal DDI, it can automatically obtain the next available IPv4 network from a specific address space or subnet. This feature automates the allocation of networks and IP addresses, so you can manage your network space more efficiently. 

BloxOne Universal DDI searches for the next available network or IP address based on the context you define when you create an object. For example, when you create a network within a specific address block, BloxOne Universal DDI searches for the next available network within the specified address block. Similarly, when you create a subnet, BloxOne Universal DDI looks up the next available IP address for that parent address block when you click on the Get next available check box. For information about creating IPv4 networks using the next available feature, see Creating Address Blocks and Creating Subnets. 

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Guidelines for theNext Available Network 

In a network, BloxOne Universal DDI searches for the next IP address that meets all of the following criteria:

• It does not match any DNS resource record, such as an A or PTR record, that is associated with an IP address.

• It is not assigned to a DHCP fixed address or a host NIOS-X Server address record.
• It is not part of any DNS bulk host NIOS-X Server record.
• It is not within any DHCP range in this network.
• It is not within an exclusion range.

In a DHCP range, BloxOne Universal DDI searches for the next IP address that meets all of the following criteria:

• It is not assigned to a fixed address or host NIOS-X Server record.
• It does not match any unmanaged IP address.
• It is not part of an exclusion range within the DHCP range.
• It is not part of a scheduled task that involves a fixed address.
• It does not match any active DHCP lease.

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