RackTables - Racktables is a nifty and robust solution for datacenter and server room asset management.
DCImanager - DCImanager is a platform for managing physical equipment. Connect any physical equipment to a single platform. Use the platform to manage your servers, switches, PDU as well as physical and virtual networks.
Opendcim - a free, web based Data Center Infrastructure Management application.
NetBox - NetBox is an open source web application designed to help manage and document computer networks. NetBox was developed specifically to address the needs of network and infrastructure engineers.
RackMonkey - RackMonkey is a tool for managing racks of equipment such as servers and switches.
Device42 - Automatically maintain an up-to-date inventory of your physical, virtual, and cloud servers and containers, network components, software/services/applications, and their inter-relationships and inter-dependencies.