Open-AudIT has a great feature list that is designed to make the task of tracking your devices simple and easy.

Features

CommunityProfessionalEnterprise
Network Discovery
Device and Software Auditing (including Device Port and Storage Appliances)
Configuration Changes Detection and Reporting
Hardware Warranty Status
Inventory Management
Custom Fields
Interactive Dashboard
Geographical Maps
Devices Export
Scheduling - discovery and reporting
Enhanced Reports including Time based, Historical and Multi Reporting
Cloud Discovery and Auditing
Customisable Options per Discovery
Rack Management
High Scale
High Availability
File Auditing
Baselines
Configurable Role Based Access Control including Active Directory and LDAP
Integration with agents and CMDB
Commercial Support
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