---
sourceDocument: Australia Telecommunications Network Inventory
sourceDocumentLink: https://servicenow-prod.fluidtopics.net/r/telecom-network-inventory

 Release :

    - australia

ft:locale :

    - en-US

ft:publication_title :

    - Australia Telecommunications Network Inventory

ft:clusterId :

    - telninv

bundleId :

    - telninv

workflow :

    - Customer and Industry


---

# Bulk allocation limits for allocated IP addresses

# Bulk allocation limits for allocated IP addresses {#ariaid-title1}

Release version: Australia  
Updated September 10, 2026  
![](https://www.servicenow.com/docs/portal-asset/ico-clock) 1 minute to read  
When you trigger bulk creation of allocated IP records from an IP Subnetwork, the system applies size limits and reserved-address rules before generating the records. This topic describes those limits and the messages displayed
when they apply.

## Maximum allocation size {#bulk-allocation-limits-for-allocated-ip-addresses__maximum-allocation-size}

A single bulk allocation operation creates at most 64 allocated IP records. The minimum prefix length supported for bulk allocation is therefore /26 for IPv4 and /122 for IPv6 --- both equate to 64 addresses.

Attempting bulk allocation on a subnetwork with a shorter (less specific) prefix is rejected with the following error:

    Subnetwork {CIDR} contains {N} addresses, which exceeds the maximum of 64 ({/26 or /122}) permitted for bulk IP Address generation. Please subdivide into smaller subnetworks before generating allocated IPs.

The {/26 or /122} placeholder is replaced with /26 for IPv4 subnetworks and /122 for IPv6 subnetworks.

## Reserved addresses generated during allocation {#bulk-allocation-limits-for-allocated-ip-addresses__reserved-addresses-during-allocation}

Bulk allocation creates one record per address in the subnetwork's CIDR. Addresses that are structurally unassignable are flagged automatically with Is Reserved = True on the resulting allocated IP records. The rule depends
on the protocol and prefix.

IPv4 subnetworks:
{#bulk-allocation-limits-for-allocated-ip-addresses__ipv4-reserved__entry__3}

| Prefix range | Addresses reserved | Notes |
|-|-|-|
| /26 -- /30 | First address (network) and last address (broadcast) | Standard IPv4 convention |
| /31 | None | Both addresses usable (RFC 3021 --- point-to-point links) |
| /32 | None | Single-host network |
[ ]

{#bulk-allocation-limits-for-allocated-ip-addresses__ipv4-reserved}

IPv6 subnetworks:
{#bulk-allocation-limits-for-allocated-ip-addresses__ipv6-reserved__entry__3}

| Prefix range | Addresses reserved | Notes |
|-|-|-|
| /122 -- /127 | First address only (Subnet Router Any cast) | RFC 4291. IPv6 has no broadcast address. |
| /128 | None | Single-address network |
[ ]

{#bulk-allocation-limits-for-allocated-ip-addresses__ipv6-reserved}
**Related tasks**   

* [Allocate IP address slots in a subnetwork](https://servicenow-prod.fluidtopics.net/GNz3ONnBMKadJjPBuzh8ZQ "Allocate IP address slots to create one Allocated IP Address record for each address in a subnetwork CIDR. Reserved addresses (the first and last for IPv4, or the first for IPv6) are flagged automatically and can't be promoted to IP Address records.")  
**Related reference**   

* [Allocated IP Address form](https://servicenow-prod.fluidtopics.net/449ooShmk06nuxpkYNhflw "The Allocated IP Address form represents a single address slot within an IP Subnetwork. The fields on this form are listed below.")