NetTool Connectivity Tester, Inline Version

It lacks only a corkscrew and a nail clipper

Network management can involve endless trial and error to identify short circuits, broken connections, mysteriously intermittent or inactive NICs, and incorrect resource allocation. What network manager wouldn’t like the ability to look at a cable and see the points where data bits leak onto the floor or where they collide against insurmountable impasses? What network manager wouldn’t like to own Fluke Networks’ NetTool Connectivity Tester (Inline Version)? This handheld version of a Swiss Army Knife for networks identifies the problems you once spent hours hunting down and verifies workstation, server, and Ethernet network topology operating parameters.

The NetTool tester, which Figure 1 shows, is the size of a fat cell phone and has a pair of RJ-45 jacks; a 7-line LCD screen; Link, Utilization, Collision, and Error status LEDs; and six buttons: up, down, right, left, select, and power. The device is compatible with 10Base-T and 100Base-TX media. NetTool can also recognize telephone company and ISDN ports; however, it can’t diagnose them.

The vendor offers two tester models: NetTool Standard and NetTool Inline. I tested NetTool Inline. Both models perform single-ended tests of network devices, including workstations, servers, cables, network jacks, and network-enabled printers. For example, these single-ended tests can verify active network jacks, show speed and duplex settings, and locate short circuits in your cable lines. Both models have flash memory upgrade capabilities.

If you purchase NetTool Standard, your first 50 uses offer NetTool Inline functionality to lure you into purchasing the upgrade. NetTool Inline lets you connect the tester to a PC and a network jack simultaneously to test desktop-to-network connectivity. NetTool Inline offers useful displays of rated and actual speeds, duplex capabilities, final link configurations, and PC resource usage.

The device’s most complex meters and monitoring functions are straightforward. The vendor provides a CD-ROM that contains both a NetTool Quick Reference Guide and a NetTool Users Manual in PDF formats. However, NetTool Inline is one of the rare intuitive products for which you might not need the manual. Nevertheless, I recommend printing a copy of the NetTool Quick Reference Guide and keeping it handy until you’re familiar with the product. Although the vendor makes the reasonable assumption that you understand how a network functions, the NetTool Users Manual explains well each type of NetTool Inline test and the test reports well.

You need to load four AA batteries into the back of the tester to bring it into service. The NetTool Inline package includes an RJ-45 patch cable that lets you connect the tester to a network jack or a PC. However, if Fluke Networks intends to get me off my knees and out from behind a PC, this 1-foot cable needs to be at least 2 feet longer.

I retrieved from my junk box a cable of suitable length and used it to test NetTool Inline’s most basic functionality: testing cables. I plugged the cable into one of the tester’s RJ-45 jacks, then hit the tester’s power button. A NetTool Inline setup icon and the AutoTest option appear on screen at startup. AutoTest is automatically highlighted. However, I highlighted and selected the NetTool Inline setup icon. Setup options govern firmware configurations (e.g., screen brightness and contrast, display of metric or English measurements, Auto Off activation). You can use the Unwanted Protocols option to configure NetTool to alert you if it detects specific protocols on a PC.

I highlighted the X in the upper-right corner of the tester’s screen, pressed the select button, and backed out of NetTool Inline Setup. I then selected AutoTest. The test immediately informed me that the attached cable was 3 feet long. I used the navigation buttons to highlight the icon that resembles a spool of cable, and the tester detected that all pairs were open―that is, my cable had no short circuits.

Having verified that my cable was in full form, I tackled a desktop-to-network connectivity test. I connected a PC’s NIC to one of NetTool Inline’s RJ-45 ports and a cable line from a network jack to the tester’s other port. The tester’s documentation calls for you to power down your PC before you connect it to the tester. You then power up the tester before the PC.

Again, I selected NetTool Inline’s AutoTest option, and NetTool exercised the connection. A network connectivity pictogram appeared, which Figure 2 shows. The underlined 100 above each connection indicates a 100Base-TX connection. An underlined 10 indicates a 10Base-T connection. An icon of two arrows pointing in opposite directions indicates duplex transmission. A sine icon indicates that the polarity is correct and the signal is strong. (To indicate reverse polarity, the sine icon appears inverted; a small sine icon indicates a weak signal.) The feature-rich pictogram also displays connected pairs. The tester’s small screen wastes no space.

You can select Problems, Protocols, Key Devices, and Health from a menu below the pictogram. These options give you even more information about the connection. If you select the PC icon from the pictogram, NetTool Inline produces a secondary menu from which you can find information about the PC’s link configurations and the IP addresses and servers it uses. You can select the network icon for information about network link configurations and IP address segment IDs.

NetTool Inline is a savvy tester, helpful for detecting network problems or mix-ups. I tested a workstation that was communicating at less than optimal speed―or so I thought. NetTool Inline easily informed me that I was mistaken; the PC had a 10Base-T adapter and not the 100Base-TX adapter I was expecting the tester to detect. NetTool Inline also detected a weak signal through a cable over which I occasionally, accidentally roll my chair. I purposely shorted out an RJ-45 connector, and the tester picked up on the short as well.

Although NetTool Inline has a steep price, don’t purchase NetTool Standard to save $600. Analyzing network problems is rarely a one-sided job, and only NetTool Inline gives you the complete picture. I admit I’m somewhat techno-glazed over NetTool Inline. However, I don’t recommend rushing out to buy NetTool Inline before you carefully consider how much labor and downtime the tester will save you. If you have two workstations and a server, the tester is a waste of money. If you’re responsible for a building full of network gear, NetTool Inline will pay for itself over a short time.