---
title: "Configuring Next Available Network"
canonical: "https://docs.infoblox.com/space/BloxOneDDI/186617449/Configuring%20Next%20Available%20Network"
format: markdown
---
When you create certain objects through 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. 

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, Universal DDI searches for the next available network within the specified address block. Similarly, when you create a subnet, 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](https://infoblox-docs.atlassian.net/wiki/spaces/BloxOneDDI/pages/186714670)* and *[Creating Subnets](https://infoblox-docs.atlassian.net/wiki/spaces/BloxOneDDI/pages/186877118)*. 

> ⚠️ ### Note
> ⚠️ 
> ⚠️ The **Get Next Available** check box is displayed only when you create a parent address block. After creating the parent address block, the **Get Next Available** check box is displayed when creating an address block or subnet within the parent address block.

<span style="color: #000000">The following diagram explains the next available network:</span>

![t_Next_Available_Network_Final.drawio.png](media://169247ba-b5dd-4562-99d7-acf8e150733b)


> Macro (excerpt)
> 
> > Macro (drawio)


<span style="color: #000000">Select the </span><span style="color: #000000">**Get Next Available**</span><span style="color: #000000"> check box when creating a subnet within an address block. In this example, subnet A already exists. Selecting the </span><span style="color: #000000">**Get Next Available **</span><span style="color: #000000">check box creates subnet automatically and assigns the available IP address. There are N number of subnets that can be created automatically depending upon the availability of leases. The maximum number of subnets that can be created (N) is 20.</span>



# <span style="color: #000000">Guidelines for the Next Available Network </span>

<span style="color: #000000">In a network, Universal DDI searches for the next IP address that meets all of the following criteria:</span>

- <span style="color: #000000">It does not match any DNS resource record, such as an A or PTR record, that is associated with an IP address.</span>
- <span style="color: #000000">It is not assigned to a DHCP fixed address or a NIOS-X Server address record.</span>
- <span style="color: #000000">It is not part of any DNS bulk NIOS-X Server record.</span>
- <span style="color: #000000">It is not within any DHCP range in this network.</span>
- <span style="color: #000000">It is not within an exclusion range.</span>

<span style="color: #000000">In a DHCP range, Universal DDI searches for the next IP address that meets all of the following criteria:</span>

- <span style="color: #000000">It is not assigned to a fixed address or NIOS-X Server record.</span>
- <span style="color: #000000">It does not match any unmanaged IP address.</span>
- <span style="color: #000000">It is not part of an exclusion range within the DHCP range.</span>
- <span style="color: #000000">It is not part of a scheduled task that involves a fixed address.</span>
- <span style="color: #000000">It does not match any active DHCP lease.</span>

> ⚠️ ### Note
> ⚠️ 
> ⚠️ <span style="color: #000000">When you select the </span><span style="color: #000000">**Get Next Available**</span><span style="color: #000000"> check box, the </span><span style="color: #000000">**Tags**</span><span style="color: #000000"> and </span><span style="color: #000000">**DHCP Options**</span><span style="color: #000000"> are disabled. You cannot assign tags or configure DHCP options when creating networks with the </span><span style="color: #000000">**Get Next Available**</span><span style="color: #000000"> option. You can edit the network once it is created and assign tags or configure DHCP options. The </span><span style="color: #000000">**Get Next Available **</span><span style="color: #000000">check box is only available when creating an address block or subnet. It is not available while editing an existing address block or subnet. </span>


> ⚠️ ### Note
> ⚠️ 
> ⚠️ <span style="color: #000000">Universal DDI does not search the Recycle Bin when creating the next available network.</span>


<span style="color: #000000">When multiple users simultaneously request for the next available network or IP address, the appliance returns the same unused network or IP address to all users. The user who first saves the task gets the next available network or IP address. In some cases, other users get an error message telling them that the network or IP address is not available when they save their tasks. They can then request another unused network or IP address or enter a new one.</span>