4 Ethereal - Interactively browse network traffic
9 S<[ B<-B> byte view height ]>
10 S<[ B<-b> bold font ]>
13 S<[ B<-f> filter expression ]>
16 S<[ B<-i> interface ]>
20 S<[ B<-P> packet list height ]>
25 S<[ B<-T> tree view height ]>
26 S<[ B<-t> time stamp format ]>
32 B<Ethereal> is a network protocol analyzer based on the B<GTK+> GUI toolkit. It lets
33 you interactively browse packet data from a live network or from a previously saved
34 capture file. Ethereal knows how to read B<pcap> / B<tcpdump> formatted capture files,
35 as well as those of B<snoop>, B<LanAlyzer>, uncompressed B<Sniffer>,
36 Microsoft B<Network Monitor>, AIX's B<iptrace>, B<NetXray>, and B<Sniffer Pro>.
44 Sets the initial height of the byte view (bottom) pane.
48 Sets the name of the bold font used for the data in the byte view
49 pane that corresponds to the field selected in the protocol tree pane.
53 Sets the default number of packets to read when capturing live
58 Specifies that the live packet capture will be performed in a separate
59 process. It is then possible to open/reload the file to display the
60 packets actually captured.
64 Sets the capture filter expression.
68 Dumps a glossary of display filter keywords to stdout and exits.
72 Prints the version and options and exits.
76 Sets the name of the interface to use for live packet capture. It
77 should match one of the names listed in "B<netstat -i>" or "B<ifconfig -a>".
81 Starts the capture session immediately; this option requires
82 the B<-i> and B<-w> parameters.
86 Sets the name of the font used by B<Ethereal> for most text.
90 Disables network object name resolution (such as hostname, TCP and UDP port
95 Sets the initial height of the packet list (top) pane.
99 Causes B<Ethereal> to exit after the end of capture session (useful in
100 batch mode with B<-c> option for instance); this option requires the
101 B<-i> and B<-w> parameters.
105 Reads packet data from I<file>.
109 Specifies that the live packet capture will be performed in a separate
110 process (same as option B<-F>) and that the packet displaying should be
111 synchronized with the capture session without human operation
112 (i.e. without load/reload). This is an experimental feature.
116 Sets the default snapshot length to use when capturing live data.
117 No more than I<snaplen> bytes of each network packet will be read into
118 memory, or saved to disk.
122 Sets the initial height of the tree view (middle) pane
126 Sets the format of the packet timestamp displayed in the packet list
127 window. The format can be one of 'r' (relative), 'a' (absolute), or 'd'
128 (delta). The relative time is the time elapsed between the first packet
129 and the current packet. The absolute time is the actual date and time the
130 packet was captured. The delta time is the time since the previous packet
131 was captured. The default is relative.
135 Prints the version and exits.
139 Sets the default capture file name.
149 =item File:Open, File:Close, File:Reload
151 Open, close, or reload a capture file.
155 Prints, for all the packets in the current capture, the packet number,
156 followed by a description of each protocol header found in the packet,
157 followed by the packet data itself. Printing options can be set with the
158 I<Edit:Preferences> menu item, or in the dialog box popped up by this
161 =item File:Print Packet
163 Print a description of each protocol header found in the packet, followed
164 by the packet data itself. Printing options can be set with the
165 I<Edit:Preferences> menu item.
169 Exits the application.
171 =item Edit:Preferences
173 Sets the packet printing and filter options (see L<"Preferences"> below).
177 Initiates a live packet capture (see L<"Capture Preferences"> below).
178 A temporary file will be created to hold the capture. The location of the
179 file can be chosen by setting your TMPDIR environment variable before
180 starting ethereal. Otherwise, the default TMPDIR location is system-dependent,
181 but is likely either /var/tmp or /tmp.
183 =item Display:Options
185 Sets the format of the packet timestamp displayed in the packet list
186 window to relative, absolute, or delta.
188 =item Tools:Follow TCP Stream
190 If you have a TCP packet selected, it will display the contents of the TCP
191 data stream in a separate window.
201 The main window is split into three panes. You can resize each pane using
202 a "thumb" at the right end of each divider line. Below the panes is a
203 strip that shows the file load progress, current filter, and informational
206 The top pane contains the list of network packets that you can scroll
207 through and select. The packet number, packet timestamp, source and
208 destination addresses, protocol, and description are printed for each
209 packet. An effort is made to display information as high up the protocol
210 stack as possible, e.g. IP addresses are displayed for IP packets, but the
211 MAC layer address is displayed for unknown packet types.
213 The middle pane contains a I<protocol tree> for the currently-selected
214 packet. The tree displays each field and its value in each protocol header
217 The lowest pane contains a hex dump of the actual packet data.
218 Selecting a field in the I<protocol tree> highlights the corresponding
219 bytes in this section.
221 A display filter can be entered into the strip at the bottom.
222 A filter for HTTP, HTTPS, and DNS traffic might look like this:
224 tcp.port == 80 || tcp.port == 443 || tcp.port == 53
226 Selecting the I<Filter:> button lets you choose from a list of named
227 filters that you can optionally save. Pressing the Return or Enter
228 keys will cause the filter to be applied to the current list of packets.
232 The I<Preferences> dialog lets you select the output format of packets
233 printed using the I<File:Print Packet> menu item and configure
234 commonly-used filters.
238 =item Printing Preferences
240 The radio buttons at the top of the I<Printing> page allow you choose
241 between printing the packets as text or PostScript, and sending the
242 output directly to a command or saving it to a file. The I<Command:> text
243 entry box is the command to send files to (usually B<lpr>), and the
244 I<File:> entry box lets you enter the name of the file you wish to save
245 to. Additinally, you can select the I<File:> button to browse the file
246 system for a particular save file.
248 =item Filter Preferences
250 The I<Filters> page lets you create and modify filters, and set the
251 default filter to use when capturing data or opening a capture file.
253 The I<Filter name> entry specifies a descriptive name for a filter, e.g.
254 B<Web and DNS traffic>. The I<Filter string> entry is the text that
255 actually describes the filtering action to take, as described above.The
256 dialog buttons perform the following actions:
262 If there is text in the two entry boxes, it creates a new associated list
267 Modifies the currently selected list item to match what's in the entry
272 Makes a copy of the currently selected list item.
276 Deletes the currently selected list item.
280 Sets the currently selected list item as the active filter. If nothing
281 is selected, turns filtering off.
285 Saves the current filter list in F<$HOME/.ethereal/filters>.
289 Closes the dialog without making any changes.
293 =item Column Preferences
295 The I<Columns> page lets you specify the number, title, and format
296 of each column in the packet list.
298 The I<Column title> entry is used to specify the title of the column
299 displayed at the top of the packet list. The type of data that the column
300 displays can be specified using the I<Column format> option menu. The row
301 of buttons on the left perform the following actions:
307 Adds a new column to the list.
311 Modifies the currently selected list item.
315 Deletes the currently selected list item.
319 Moves the selected list item up or down one position.
323 Currently has no effect.
327 Saves the current column format as the default.
331 Closes the dialog without making any changes.
337 =item Capture Preferences
339 The I<Capture Preferences> dialog lets you specify various parameters for
340 capturing live packet data.
342 The I<Interface:> entry box lets you specify the interface from which to
343 capture packet data. The I<Count:> entry specifies the number of packets
344 to capture. Entering 0 will capture packets indefinitely. The I<Filter:>
345 entry lets you specify the capture filter using a tcpdump-style filter
346 string as described above. The I<File:> entry specifies the file to save
347 to, as in the I<Printer Options> dialog above. You can choose to open the
348 file after capture, and you can also specify the maximum number of bytes
349 to capture per packet with the I<Capture length> entry.
351 =item Display Options
353 The I<Display Options> dialog lets you specify the format of the time stamp
354 in the packet list. You can select "Time of day" for absolute time stamps,
355 "Seconds since beginning of capture" for relative time stamps, or
356 "Seconds since previous frame" for delta time stamps.
360 =head1 DISPLAY FILTER SYNTAX
362 The grammar used for B<Ethereal>'s display filter syntax is similar to
363 the syntax of the C programming language.
365 =insert_dfilter_table
369 L<tcpdump(1)>, L<pcap(3)>
373 The latest version of B<ethereal> can be found at
374 B<http://ethereal.zing.org>.
380 Gerald Combs <gerald@zing.org>
385 Gilbert Ramirez <gramirez@tivoli.com>
386 Hannes R. Boehm <hannes@boehm.org>
387 Mike Hall <mlh@io.com>
388 Bobo Rajec <bobo@bsp-consulting.sk>
389 Laurent Deniel <deniel@worldnet.fr>
390 Don Lafontaine <lafont02@cn.ca>
391 Guy Harris <guy@netapp.com>
392 Simon Wilkinson <sxw@dcs.ed.ac.uk>
393 Joerg Mayer <jmayer@telemation.de>
394 Martin Maciaszek <fastjack@i-s-o.net>
395 Didier Jorand <Didier.Jorand@alcatel.fr>
396 Jun-ichiro itojun Hagino <itojun@iijlab.net>
397 Richard Sharpe <sharpe@ns.aus.com>
398 John McDermott <jjm@jkintl.com>
399 Jeff Jahr <jjahr@shastanets.com>
400 Brad Robel-Forrest <bradr@watchguard.com>
401 Ashok Narayanan <ashokn@cisco.com>
402 Aaron Hillegass <aaron@classmax.com>
403 Jason Lango <jal@netapp.com>
404 Johan Feyaerts <Johan.Feyaerts@siemens.atea.be>
405 Olivier Abad <abad@daba.dhis.org>
406 Thierry Andry <Thierry.Andry@advalvas.be>
408 Alain Magloire <alainm@rcsm.ece.mcgill.ca> was kind enough to give his
409 permission to use his version of snprintf.c.
411 Dan Lasley <dlasley@promus.com> gave permission for his dumpit() hex-dump