From e18dc43aae8b06652ac04f46cf452cdfd5e199a0 Mon Sep 17 00:00:00 2001
From: jeremystretch <jstretch@ns1.com>
Date: Mon, 3 Jan 2022 09:17:15 -0500
Subject: [PATCH] Fixes #8196: Fix IndexError exception when viewing large IPv6
 prefixes in UI

---
 docs/release-notes/version-3.1.md |  3 ++-
 netbox/templates/ipam/prefix.html | 12 +++++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/docs/release-notes/version-3.1.md b/docs/release-notes/version-3.1.md
index 90c7520e2..c994d8305 100644
--- a/docs/release-notes/version-3.1.md
+++ b/docs/release-notes/version-3.1.md
@@ -9,8 +9,9 @@
 
 ### Bug Fixes
 
-* [#8191](https://github.com/netbox-community/netbox/issues/8191) - Fix return URL when adding IP addresses to VM interfaces
 * [#8187](https://github.com/netbox-community/netbox/issues/8187) - Fix rendering of tags column in object tables
+* [#8191](https://github.com/netbox-community/netbox/issues/8191) - Fix return URL when adding IP addresses to VM interfaces
+* [#8196](https://github.com/netbox-community/netbox/issues/8196) - Fix IndexError exception when viewing large IPv6 prefixes in UI
 
 ---
 
diff --git a/netbox/templates/ipam/prefix.html b/netbox/templates/ipam/prefix.html
index c3d3bdedd..cb62e56ae 100644
--- a/netbox/templates/ipam/prefix.html
+++ b/netbox/templates/ipam/prefix.html
@@ -1,4 +1,5 @@
 {% extends 'ipam/prefix/base.html' %}
+{% load humanize %}
 {% load helpers %}
 {% load plugins %}
 
@@ -124,9 +125,18 @@
                 <a href="{% url 'ipam:prefix_ipaddresses' pk=object.pk %}">{{ child_ip_count }}</a>
               </td>
             </tr>
+          {% endwith %}
+          {% with available_count=object.get_available_ips.size %}
             <tr>
               <th scope="row">Available IPs</th>
-              <td>{{ object.get_available_ips|length }}</td>
+              <td>
+                {# Use human-friendly words for counts greater than one million #}
+                {% if available_count > 1000000 %}
+                  {{ available_count|intword }}
+                {% else %}
+                  {{ available_count|intcomma }}
+                {% endif %}
+              </td>
             </tr>
           {% endwith %}
           <tr>