---
title: "Understanding SPM Polling"
canonical: "https://docs.infoblox.com/space/netmri754/105942441/Understanding%20SPM%20Polling"
format: markdown
---
> ⚠️ Switch Port Management (and its polling functions) operates only with devices detected as Switches or Switch-Routers in NetMRI. For more information, see *[Performing On-Demand Switch Port Polling](https://infoblox-docs.atlassian.net/wiki/spaces/netmri754/pages/105942519)**[.](http://infoblox-docs.atlassian.net/wiki/pages/resumedraft.action?draftId=15698418#SwitchPortManagement-PerformingOn-DemandSwitchPortPolling)*

Network device polling is the key mechanism for building Switch Port Management (SPM)'s switching information, and the polling features provide considerable flexibility. You use polling at the Device Group level to check for changes to any active device in that group. You can define polling time periods for individual device groups so that administrators have near-real-time capabilities for monitoring large-scale switched networks, or specific parts thereof, and quickly detect and address problems.

In all cases, a polling schedule indicates the start of a polling cycle. Any given network device may not be polled at the specific time when the scheduled polling cycle begins. This is particularly likely when many devices are being polled during the cycle. The duration of a polling cycle may take some time.

> ⚠️ The **Settings** icon > **Setup** > **Collection** **and** **Groups** > **Global** tab provides the appliance-wide settings for polling all Switch and Switch-Router devices in the network.

NetMRI provides several polling and discovery optimizations under Advanced Settings. For more information, see *[Changing Advanced SPM Settings](https://infoblox-docs.atlassian.net/wiki/spaces/netmri754/pages/105942815)*.