Minimize Documentation Dilemma
A well-documented network is more than a list of all of its PCs, laptops, servers andhubs. It's the network's manual. The problem is that it's one of those projects for when"things slow [DEMO] bit." Fortunately, two companies have released new softwareto help get it done. Network Charter Pro by Micrografx, Inc. (Richardson, Texas) and VisioEnterprise 5.0 by Visio Corporation's (Seattle, Wash.) make documenting if not a pleasantexperience, at least a quicker and easier one.
Both packages feature auto discovery, which searches and automatically detectsnetworked devices and diagrams and documents network connections. While both packagesperform auto-discovery (even calling it the same thing), they do it differently.
MAGNA CHARTER
With Network Charter Pro you begin discovery by entering the IP address of your localsubnet or any SNMP community names you use. It pings each IP address on the subnet,records any devices that answer and performs a reverse DNS lookup to return the host name.It then tries to locate any SNMP-managed devices based on the community names and returnwhat information it can. Lastly, Network Charter Pro can query any Windows or NetWareserver and return information such as domain names and software versions.
Discovery on a 30 node, 10 Base-T network segment took about 2.5 minutes. A segmentwith 160 devices took about 20 minutes. The discovery was complete. Every device in mytest network was discovered.
The Visio Enterprise process is similar. But Visio adds functionality by allowing youto specify a seed router to query that in turn, is used to discover other network segmentsand routers, allowing the process to map an entire network in a single pass. NetworkCharter Pro offers no function to automatically cross segments. You must manually connectto each segment to perform discovery.
Visio relies almost completely on SNMP queries in its discovery process. Every deviceon the segment is pinged, but not all answers are recorded. Apparently, after a successfulping, an SNMP query is done.
If the device responds to that query, it's included in the discovery. Because not allthe devices in my test network used SNMP, the network was not completely discovered. Tocreate a diagram of your network, you'll have to manually add any devices without IPaddresses or those that are not SNMP-managed. This may include devices such as networkhubs or switches.
Both packages offer a library of realistic images and icons. For instance, if you wantto represent your Cisco router, select an icon from a list of Cisco models. They look justlike the real thing, right down to the logo.
You can also document the contents of individual network devices. Both packagesmaintain lists of properties for each item. Such things as the purchase date, servicecontract numbers, serial numbers and notes on Year 2000 compliance can be re-corded.
Which package to choose? I liked Network Charter Pro's auto discovery over Visio's.Because Micrografx doesn't solely rely on SNMP, they're able to discover more devices. Theinformation returned may not be as complete as the information an SNMP query can return,but at least they're included and can be updated manually.
NETWORKED CHASMS
Many network managers are now trying to close the gaping hole in their security thatpoorly implemented SNMP can present. By relying solely on SNMP, Visio may not be returninga complete picture of your network. But, if you have many segments in your network usingSNMP, Visio's ability to automatically cross network segments is a big time saver.
Visio offers a better library of diagramming images. The software CD is packed withproduct icons from not only the usual vendor suspects such as Cisco, Compaq and 3Com, butalso includes some, such as rack manufacturers and distributors, that are a surprise.Micrografx seems to be playing catch up in this area. Both vendors offer subscriptionservices to provide you with the latest sets of product images from various manufacturers.
Visio provides several other significant features in Enterprise 5.0. For instance,software and database modeling, which includes such things as relational databasemodeling, UML diagramming and connections to Microsoft's Visual Studio, allow you to modelcode.
You owe it to yourself and your co-workers to provide the best possible documentationand either package can offer significant help. Make the time to document your network.