C H A P T E R  40

Network Hardware Test (nettest)

nettest Description

nettest checks all the networking hardware on the system CPU board and separate networking controllers (for example, a second SBus Ethernet controller). The machine under test must be attached to a network with at least one other system on the network.

Note - This version of nettest is used for all networking devices, including Ethernet (ie and le), token ring (tr, trp), quad Ethernet (QED), fiber optic (fddi, nf, bf, pf), SPARCclustertrademark 1 system (em), ATM (sa, ba), HiPPI, 100-Mbits per second Ethernet (be,hme), and GigaSwift Ethernet (ce) devices.

The nettest mainly uses the Internet Control Message Protocol (ICMP), and requires at least two machines on a network--the machine under test and another machine reliable enough to be a test target. Both machines must support the Transmission Control Protocol/Internet Protocol (TCP/IP) (ICMP is part of TCP/IP). The target machine must either be configured to respond to ICMP broadcast or to RPC broadcast.

First nettest determines the target machine(s) to test against. If no targets are specified, it sends an ICMP broadcast to find them. If the test fails to find all necessary nettest targets, it tries RPC broadcast to the RPC port mapper daemon. If you specify the targets, nettest uses the specified target(s) instead.

After finding the necessary targets, nettest performs the following tests:

Note - nettest is a scalable test. However, the maximum number of networked devices allowed on a system is 255, and the number of instances for each device is limited to 2. If you start the SunVTS exerciser using the -i option to specify a default number of instances for all tests, nettest cannot assign more than 2 instances per each networked device.

nettest Options

To reach the following dialog box, right-click on the test name in the System Map and select Test Parameter Options. If you do not see this test in the System Map, you might need to expand the collapsed groups, or your system might not include the device appropriate to this test. Refer to the SunVTS User's Guide for more details.

FIGURE 40-1 nettest Test Parameter Options Dialog Box

Screenshot of the nettest Test Parameter Options dialog box

The Configuration section specifies the host name, host ID, host address, and domain name of the system being tested.

TABLE 40-1 nettest Options

nettest Options


Target Host

Specifies one or more targets to be tested against. Target host entries can be either a host name or an Internet address. When no target host is specified, the test finds necessary targets through broadcasting. The default setting leaves this field empty.

Receive Timeout field

The default is 120 seconds, but can be changed. Use a range from 0 to 600 seconds.

Number of Retries field

The default number of retries before flagging an error is three, but can be changed. Use a range between 0 to 128 retries.

Print Warning

Disabled by default. Click Enable to see warning errors, such as retry on timeout.

nettest Test Modes

Both Connection and Functional test modes are supported by nettest. Different test schemes are performed on the network device based on the mode selected.

TABLE 40-2 nettest Supported Test Modes

Test Mode



Checks whether the device is connected. It searches through all the network interfaces for a specified device name. If nettest does not find the device connected, the test fails; otherwise it returns:
device is connected.


Performs all three tests (Random test, Incremental test, and Pattern test) sequentially. You may specify options that performs heavy stress testing.


Performs only the Random test.

nettest Command-Line Syntax

/opt/SUNWvts/bin/nettest standard_arguments -o target=h1+h2+..., dev=interface,test=type,packets=n,pattern=hex,timeout=seconds, retry=n,warn

TABLE 40-3 nettest Command-Line Syntax




A list of test targets by host name or Internet address.


Network interface name. The default value is le0 for Ethernet networks.


The test type Random, Increment, or Pattern for the desired test. The default value is Random+Increment+Pattern (all tests).


Number of random/pattern packets. The default is 256.


Specifies a data pattern, in hexadecimal form. The default is all patterns from 0 to 0xff.


Indicates the number of seconds to wait before a timeout. The default is 120 seconds.


Indicates the number of test timeout retries. The default is three retries.


When enabled, prints warning messages.