Everyone who backpacks can rattle off the 10 essentials by rote - map, compass, torch, extra food and clothes, sunglasses, first-aid kit, knife, waterproof matches, fire-starter. They are the critical and essential tools needed as insurance against the unexpected.
Likewise, network managers rely on must-have troubleshooting tools for diagnosing problems with the network, servers and desktop PCs. What follows are the 10 tools network managers deem essential to their network management arsenals.
1. Configuration inventory: An inventory of the configuration of workstations and servers on the network is instrumental in being able to suss out the source of trouble, according to Mark Moroses, senior director of technical services and security officer at Maimonides Medical Centre in New York. "This can be on paper, but it cannot become suspect - the data has to be maintained and trusted," he says. "It is priceless to know the exact configuration of equipment inside the problem domain."
Moroses uses Bindview's NETinventory for this purpose. Another popular option is Tally Systems TS Census, a product that Novell recently acquired and added to its ZENworks Asset Management.
2. Network diagramming software: "You cannot troubleshoot a network issue without an accurate, complete understanding of the equipment involved, and for that you must be sure of the communication path," Moroses says.
Network diagramming software is key to establishing the critical links between network gear. Microsoft's Visio 2003 is the market leader for diagramming the physical configuration of the network. Users can download a trial version here.
3. A device polling system: A simple piece of software that automatically polls network devices - servers, switches, printers and routers - to see if they are connected also is important. When a device doesn't respond to a poll, it is usually the first signal of trouble.
"Polling is an accurate, clear method for assessing the scope of the problem," Moroses says. "For example, multiple devices in multiple locations may be affected at the same time."
He adds that relying on users to complain that a printer isn't working or that they can't connect to the network is usually misleading and results in IT staff taking longer to diagnose the problem. While SNMP traps can be useful, simple ping polling is worth its weight in gold.
Ronald Godine, manager of IS operations for Royal Appliance in Ohio, recommends SolarWind's Network Management Toolset. "A copy of SolarWinds will let you interact with a variety of devices and map ports on a switch," he says.
Many devices such as Cisco routers and switches also ship with a device polling configuration option. Fidelia's NetVigil also provides for device polling of any SNMP-enabled device.
4. Application logs: Each application such as Oracle provides a log file of error codes. Moroses says that he has found that by reviewing the logs early in the troubleshooting process he can reduce the size of the fault domain. He says application logs are especially effective when used in combination with network device logs. Most applications generate logs of errors that will tell the IT manager that a process terminated and for what reason.
5. Network device logs: Reviewing network device logs for switches, routers and other network gear also can help define and diagnose a problem quickly. When a network manager configures the system so that all logs are sent to a central source - a syslog on the server - they can be particularly helpful. A freely downloadable syslog server is available from Kiwi Enterprises.
6. Microsoft Excel: Some tools such as Excel come already installed in a network manager's kit. Using Excel to compare log entries for multiple network devices can help identify patterns. Since most logs are time-stamped, Excel spreadsheets represent a good way to see "an entire forensic picture," Moroses says. Users in open source environments might be interested in the OpenOffice Calc spreadsheet available for free download.
7. Remote control software: As with any organisation spread out over a wide area, a remote control tool is extremely useful in checking theories, or patching or reconfiguring remote devices or workstations. Both Moroses and Godine say it reduces problem resolution time significantly. Popular tools include Symantec's PCAnywhere, Funk Software's Proxy, VNC (Virtual Network Computing) and CrossTec's NetOp Remote Control. Godine favours Funk's Proxy for his remote control needs.
Shane Wilson, co-ordinator of network services for Centre College in Kentucky, uses the open source tool Putty to remotely access servers and devices. "Putty is the best client I've found for remote access to servers and devices that provide SSH [Secure Shell] remote access," he says.
8. A protocol analyser or cable tester: For complicated connectivity issues, a hardware- or software-based protocol analyser is essential. There are some issues that cannot be diagnosed without packet-level inspection.
Finisar's XGig Analyser Suite, the Ethereal protocol analyser and Flukes OptiView Protocol Expert are popular choices. Tripplet Fox & Hound wire tracing kit also can be used to troubleshoot wiring problems. "If you build the network right, you don't often need to go to that level," Godine says. "We've used analysers in the past when we needed to find out where the bad cable was. Today, we are running into wireless problems; a packet analyser would be helpful"
"You need to be able to rule our physical layer problems," says Wilson, who uses cable testers from Fluke or Microtest. He also uses Ethereal's freely downloadable open source protocol analyser. "Sometimes you just have to get down and see what data is being passed back and forth on your network to solve a networking issue," he adds.
9. The Internet: Another tool of daily use, it can be invaluable for researching complicated problems, device configurations or finding patches, Moroses says. HP's site has a wealth of patches available and Novell's NetWare and other fora offer a fair degree of accurate advice. Wilson says the Internet also gives him a plethora of information. "The ability to get help, download drivers and find documentation on the Internet make all of the difference," says Wilson. "I don't know how I would do my job with out all of the informational resources of the Net."
10. Imaging software: Moroses uses Symantec's Norton Ghost to reconfigure and re-provision workstations. "The issue is being able to reload any device to a known good copy, virus free," he says. "Not only is it nice for building new machine, but by making it a 10-minute process, it can also be used to take possible theories 'off the table' by making sure the live configuration is valid."
Other imaging software includes Altiris' Client Management Suite and Microsoft's Remote Installation Services.