GUESSNET-SCAN(8) System Manager's Manual GUESSNET-SCAN(8)NAME
guessnet-scan - guess network configuration data by looking at network traffic
SYNOPSIS
guessnet-scan [options] [ethernet_interface]
DESCRIPTION
Guessnet-scan tries to deduce network configuration data by watching network traffic at a given Ethernet interface.
After scanning network traffic for some time, guessnet-scan prints a configuration string suitable for inclusion in /etc/network/inter-
faces.
Note that guessnet-scan uses heuristics and wild guesses and that the resulting data is not guaranteed to be accurate. The program is
intended to be used as a first try at getting network configuration data without bothering anyone.
OPTIONS
Options follow the usual GNU conventions,
--debug
Print debugging messages.
--help Show a brief summary of commandline options.
--init-time=int
Time in seconds to wait for the interface to initialize when it is not found already up at program startup. Default: 3 seconds.
-t, --timeout=int
Time in seconds to watch for network traffic. Default: 5 seconds.
-v, --verbose
Operate verbosely.
--version
Show the version number of the program.
SCANNING REQUIREMENTS
To correctly identify all data of the local network, guessnet-scan needs to see traffic related to a host in the local network and to the
local gateway, if any.
To be able to identify the network gateway, guessnet-scan also needs to see some traffic directed to the external network: you can help the
detection by generating some outbound IP traffic during the scan, for example by browsing a web page (without proxy) or using telnet to
open a connection to some remote host.
Note that if you are connected to a switch, guessnet-scan won't probably be able to work, since the switch will isolate it from the network
traffic that the other machines are generating.
SEE ALSO guessnet(8), interfaces(5).
AUTHOR
Guessnet-scan was written by Enrico Zini <enrico@debian.org>.
10 October 2004 GUESSNET-SCAN(8)
Check Out this Related Man Page
niffconfig(8) System Manager's Manual niffconfig(8)NAME
niffconfig - Configuration program for the Network Interface Failure Finder (NIFF)
SYNOPSIS
/usr/sbin/niffconfig [-a] [-m] [-r] [-s] [-u] [-v] [-d num] [-o num] [-t num] [interface1 interface2...]
OPTIONS
Adds an interface or interfaces, specified by the interface parameter. You cannot specify the -a option with the -m, -s, -r, or -u options.
Specifies the time period, in seconds, that the traffic monitor thread uses between reads of the interface counters when it suspects there
is a connectivity problem. This number must be smaller than the number given for the -t option. The default time period is 5 seconds. If
num is not specified, niffconfig uses the default. Specifies the total number of traffic-free seconds that must elapse before the traffic
monitor thread determines that a network interface has failed. This number must be at least the sum of the -d option and two times the -t
option. That is, given the default time period for -d and -t, the -o option must be at least 20 seconds. The default time period for this
option is 60 seconds. If num is not specified, niffconfig uses the default. Modifies the timing parameters of an interface that is already
being monitored. Typically, this option is specified along with one or more of -t num, -d num, or -o num options. If none of these parame-
ters are specified, the default value is used. You cannot specify the -m option with the -a, -s, -r, or -u options. Stops monitoring the
specified interface. Obtains the status of the specified interface. Specifies the time period, in seconds, that the traffic monitor
thread delays between reads of the interface counters when the network is running normally. The default time period is 20 seconds. If num
is not specified, niffconfig uses the default. Displays the status of all interfaces currently being monitored to standard out (stdout).
Displays the status, timer values, and description (verbose mode) of all interfaces currently being monitored to standard out (stdout).
DESCRIPTION
The niffconfig command arranges for one or more network interfaces to be monitored for possible loss of connectivity. Timing parameters
that govern how quickly an interface can be declared suspect or dead may be manipulated with this command. You can specify multiple inter-
faces, separated by a space, on the command line. Note, you must be superuser to use the niffconfig command.
Except for the -u and -u options, all niffconfig options require one or more network interfaces to be specified.
EXAMPLES
To add the tu0 and tu1 interfaces to the list of monitored interfaces, enter: # niffconfig -a tu0 tu1 To change the time it takes to
declare failure on the tu1 interface to 90 seconds, enter: # niffconfig -o 90 tu1 To display the status of all interfaces that are being
monitored: # niffconfig -u To stop monitoring the tu0 interface: # niffconfig -r tu0
SEE ALSO
Daemons: niffd(8)
Information: EVM(5), nifftmt(7)niffconfig(8)