---
title: "Creating a Child Device Group"
canonical: "https://docs.infoblox.com/space/netmri760/357174570/Creating%20a%20Child%20Device%20Group"
format: markdown
---
Child device groups should only contain devices belonging to their parent group. Creating a child device group of the top-level group “Routing” and using a device group criteria regular expression to filter other devices (e.g., firewalls) will result in an empty device group.

The group membership criteria statements built into each device group, respectively:

`$Assurance > 75 and $vendor eq "Cisco" and $type in ["Router","Switch-Router"]`

`$Assurance > 75 and $vendor eq "Juniper" and $type in ["Router","Switch-Router"]`

> ⚠️ **Note**
> ⚠️ 
> ⚠️ When you create a child device group for an existing device group, the existing group changes its icon to a folder icon. That folder icon does not change the essential properties of the parent device group–the parent keeps all of its qualifying devices.

To create a new child device group, complete the following:

1. Click the** Settings** icon > **Setup** > **Collection** **and** **Groups** > **Groups**.
2. Right-click a device group and select **Add** > **Child** from the shortcut menu.   
The **Add** **Device** **Group** dialog appears.
3. Select either **Basic** or **Extended**. By default, **Basic** is selected. For more information about extended device groups, see [*Creating Extended Device Groups*](https://infoblox-docs.atlassian.net/wiki/spaces/netmri760/pages/357535200).
4. In the **Parent ID** field, NetMRI automatically sets the ID of the parent group.
5. Enter a **Name** for the new child group. The group name is shown in all group-related displays and reports, so the group name should be meaningful without being too long.
6. Enter a **Membership** **Criteria** regular expression. For more information, see [*Understanding Device Group Membership Criteria*](https://infoblox-docs.atlassian.net/wiki/spaces/netmri760/pages/357467839).
7. Click **Save** **&** **Close** or **Save** **&** **New**.

> ⚠️ **Note**
> ⚠️ 
> ⚠️ Nested device groups also operate with Issue Analysis. For information, see [* Issue Analysis in NetMRI *](https://infoblox-docs.atlassian.net/wiki/spaces/netmri760/pages/357566268) and its subsections. Nested device groups inherit their Issue settings from their parent device groups, and may need editing to suppress Issues that are not relevant to them.