Network inventory management: A method to the madness

Tag : network switch router

Creating a network inventory report is a daunting task, in the faceof massive amounts of data to be collected and incorrectly reportedinformation to be cropped or corrected. In order to make sense ofthe madness, VARs and consultants need a sensible and efficientmethod. The ends, however, justify the means, as a successfulinventory will provide a complete picture and assist the discoveryof issues in need of resolution.

An inventory includes collecting host identificationinformation, such as IP address, network interface hardware (NIC)address and DNS entries, for all network nodes. While some of thisinformation will be on hand in most environments, often it willhave errors. In most cases, NIC information and MAC addresses willnot be recorded.
 
A good network inventory is the result of a well planned strategyand process. This involves understanding why information like IP,MAC and DNS are important. From there, a VAR is free to exploremethods for collecting the data, such as spreadsheets and notepads.
 
Taking the inventory tally also involves tools, such as scripts, toassist in the data collection. Some good tools include: vidump.sh arpextract.sh dnsdump.sh activehosts.sh ouiresolv.pl ouilookup.sh gen-net-inv.pl Learn more about taking a network inventory and host identification data collection .

The reporting aspect of the network inventory should yield threethings: A listing of all the active hosts on an IP subnet at the time theinventory was run Information on inconsistencies between ICMP collection and therouter/switch's visibility of the subnet Inconsistencies between what is active on the subnet and what is inDNS.