Racktables is a nifty and robust solution for datacenter and server room asset management. It helps document hardware assets, network addresses, space in racks, networks configuration and much much more!
HaCi is an IP Address / Network Administration Tool with IPv6 Support. It stores its data efficiently in a relational Database and uses a treelike Strukture to illustrate supernets and subnets. Additional (template) data can be linked to each network