Management on the cheap

Here are 10 network and systems management tools that are free (or awfully close to it).

By Jeff Caruso
Network World, 05/10/99

Consider the simple, nearly ubiquitous utility called ping. It's a network manager's first reflex, the first tool in the toolbox.

Need to know if a server is reachable over a network? Ping it.

Ping, however, is just one of many useful and free management utilities readily available to network managers. In a large enterprise, such tools can be used to supplement commercial management tools and platforms. In a small environment, they may be all you have.

It's surprising how much free stuff is available. In addition to utilities such as ping and traceroute that ship with Unix and other operating systems, shareware and freeware management tools abound. Many network managers have grown frustrated with management software on the market; some have written their own quick tools to solve a problem and thrust them into the public domain.

Should an organization trust its network to free tools? Strategies differ. Some managers use the tools in conjunction with major network management software. Others use them as a backup system if the management platform fails. Still others depend on the tools everyday.

"In the old days, telnet, File Transfer Protocol, ping and traceroute were about all you needed to keep a small IP network running smoothly," says Mike Myrick, manager of network development and engineering services at the University of Mississippi. Over the past 20 years, the school has grown from a few hundred nodes to 13,400 connections.

"Contrary to what you might think, I still rely heavily on these simple tools," Myrick says. He combines them with other free tools, such as Scotty and Multi Router Traffic Grapher (MRTG).

"Using public domain and home-grown management tools is cheap and easy on a small scale," says Deke Kassabian, technical director at the University of Pennsylvania. "But once the scale gets large enough, there is a tendency to develop frameworks to use the tools together and to design common databases to help correlate their data. Real network management for large networks probably can never be done cheaply."

Kassabian prefers to use a combination of free utilities and commercial software. He combines vendor tools such as Cabletron's Spectrum, Concord's Network Health and Network Associates' Distributed Sniffer with ping, traceroute, mon and swatch.

Here are 10 management tools that can get you started managing on the cheap, in no particular order.

This is not an all-inclusive list - in fact, if there are other tools you swear by, let us know by e-mailing us at jcaruso@nww.com.

1. Ping (of course)

Ping, which some say stands for Packet InterNet Groper, has been around since 1983.

The program lets you know if one device can reach another over a network. Ping does this by sending an echo request using Internet Control Message Protocol.

This free utility has been ported to major operating systems, including Unix variants, and Windows NT and 95.

2. Traceroute

Another common utility is traceroute. It's similar to ping, in that traceroute demonstrates if a packet can make it from one device to another.

But traceroute also displays the route the packet takes through the Internet and the time it takes to get from one hop to the next. By demonstrating these things, traceroute can show where delays are the greatest and where trouble spots may exist.

3. MRTG

MRTG monitors the traffic load on network links. The software collects traffic data from routers via SNMP and displays the data in a graph on a Web page.

MRTG keeps data over long periods of time, showing traffic trends for the past week, month or year. Network managers can configure MRTG to collect and display trends on any SNMP variable.

Many managers use MRTG to graph network trends, says Scott Parker, chief technology officer at Southernview Technologies, a consultancy based in Atlanta.

"Who wants to go buy SAS [Institute software] just to do graphs?" he asks.

4. Scotty

This utility is a network management platform based on the Tool Command Language. With it, network managers can write scripts to automate network tasks. Scotty discovers what devices are connected to a network, filters events, provides for troubleshooting and includes a browser to look at an SNMP management information base.

"Scotty is not as extensible as Hewlett-Packard's OpenView or SunNet Manager, but it performs the basic functions I really need, at no cost," the University of Mississippi's Myrick says.

5. QueSO

Que Sistema Operativo (QueSO) is a utility that can tell you what operating systems are running on remote hosts by sending TCP packets that don't make sense to the host.

Standards don't define how operating systems should respond to nonsensical packets, so each operating system has a distinctive response. QueSO compares the response against a list of known operating systems and lets you know if it finds a match.

6. Nmap

Like QueSO, nmap scans the network for hosts, revealing what operating system and services those hosts are running.

Nmap sends out parallel pings to all servers on a network to see which ones are up, and it scans for TCP ports to see what services - such as e-mail and Web pages - are available on the server.

7. Tcpdump

The Unix utility tcpdump prints out the headers of packets that go through the computer's network interface.

Network managers can filter out the specific packets for which they're looking. They can look at packets using a particular protocol, check for those bound for a specific destination or find packets by using a certain TCP port number.

8. Mon

Mon is software that can monitor network resources, watching for server problems and ensuring that services such as Web pages and e-mail stay available. Network managers can configure mon to watch the service of their choice and generate an alert if that service goes down.

9. Swatch

No relation to the manufacturer of precision timepieces, swatch, or Simple Watchdog, is another Unix utility. It monitors messages written to the Unix system message log. Based on what messages are written there, swatch can take actions to notify a network administrator. For instance, if the file system is full, swatch could notify the administrator by sending an e-mail message.

10. WhatsUp Gold

The product can tell network managers when a device or service fails. Ipswitch this month is shipping Version 4.0 of the utility, which adds reporting capabilities.

The software keeps a running tab of how often and for how long devices go down, and generates reports on the information. Network managers often use the product as a backup to other commercial network management systems.

There are plenty of other free utilities available, including some on the security side. Even if you use commercial management products, your toolbox is not complete without at least a few of these free tools in it. o