1 .\" Copyright (c) 2003 Hidetoshi Shimokawa
2 .\" All rights reserved.
4 .\" Redistribution and use in source and binary forms, with or without
5 .\" modification, are permitted provided that the following conditions
7 .\" 1. Redistributions of source code must retain the above copyright
8 .\" notice, this list of conditions and the following disclaimer.
9 .\" 2. Redistributions in binary form must reproduce the above copyright
10 .\" notice, this list of conditions and the following disclaimer in the
11 .\" documentation and/or other materials provided with the distribution.
13 .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 .\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
15 .\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
16 .\" DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
17 .\" INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
18 .\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
19 .\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
21 .\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
22 .\" ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
23 .\" POSSIBILITY OF SUCH DAMAGE.
38 .Op Fl e Ar escape-char
40 .Op Fl C Ar console_port
47 .Op Fl C Ar console_port
55 utility is designed to provide a way for users to access
57 (dumb console device) on a local or remote system.
60 utility interacts with
66 and interacts with the user over TTY or TCP/IP.
71 you have to specify target EUI64 address using the
73 option. Physical DMA should be enabled on the target machine for access
80 driver communicate using 2 ports, one for the console port and another
84 Users are supposed to access
90 You can specify listen ports for console and
97 The port number 0 has special meaning that
98 current TTY (stdin/stdout) is used instead of TCP/IP.
99 A negative port number will disable the port.
104 acts as a slave device and
106 acts as a master device with
109 Typed characters are normally transmitted directly to
111 A escape character (the default is
113 ) appearing as the first character of a line is an escape signal; the
114 following are recognized:
115 .Bl -tag -width ident
117 Drop the connection and exit.
119 Invoke kgdb on the terminal on which dconschat is running.
121 Reset the target over FireWire if a reset address is registered in Configuration ROM.
123 Suspend the dconschat process.
126 The following options are supported.
128 .Bl -tag -width indent
130 Translate Ctrl-C to ALT_BREAK (CR +
136 Replay old buffer on connection.
138 Verbose debug output.
141 options increase verbosity.
143 Listen on a wildcard address rather than localhost.
146 Do not write anything to the
150 Enable ad-hoc workaround for the TELNET protocol to
151 remove unnecessary byte sequences.
152 It should be set when you access
158 Read available buffer, then exit.
162 .It Fl e Ar escape-char
163 Specify escape character.
166 Specify polling rate.
167 The default value is 100.
168 .It Fl C Ar console_port
169 Specify the console port.
170 The default value is 0 (stdin/stdout).
175 The default value is \-1 (disabled).
179 Specify system file such as
180 .Pa /boot/kernel/kernel .
181 .It Fl t Ar target_eui64
182 Specify the 64-bit extended unique identifier of the target,
183 and use FireWire to access remote
186 Specify the physical I/O address of the
192 If this option is not specified,
194 tries to get the address from the Configuration ROM on the target.
195 You are supposed to enable
197 on the target to omit this option.
199 Specify FireWire bus number.
203 .Bl -tag -width indent -compact
211 with FireWire for remote
213 you have to specify the EUI64 of the target.
214 You can obtain EUI64 by running
217 The first EUI64 is of the host running
219 and others on the bus follow.
220 .Bd -literal -offset indent
222 2 devices (info_len=2)
224 1 77-66-55-44-33-22-11-00 0
225 0 00-11-22-33-44-55-66-77 1
228 The EUI64 does not change unless you change the hardware
229 as the ethernet address.
233 .Bd -literal -offset indent
234 # dconschat -br -G 12345 -t 00-11-22-33-44-55-66-77
237 You will get console output of the target and login prompt if a
241 You can break to DDB with ALT_BREAK (CR +
247 .Dv ALT_BREAK_TO_DEBUGGER
248 are enabled in the target kernel.
249 To quit the session, type CR +
257 port is almost the same as remote
259 over serial line except
260 using TCP/IP instead of
263 .Sx "On-line Kernel Debugging Using Remote GDB"
265 .%T "The FreeBSD Developers Handbook"
269 .Bd -literal -offset indent
270 % gdb -k kernel.debug
271 (kgdb) target remote :12345
276 is attached and you specified the
282 causes a break to debugger.
284 The following command gets the console log from the crash dump:
285 .Bd -literal -offset indent
286 # dconschat -1 -M vmcore.0 -N kernel.0
289 If you want access to the console using
292 .Bd -literal -offset indent
293 # dconschat -rTC 5555 &
294 # telnet localhost 5555
297 You may want to keep logging console output of several machines.
299 in the Ports collection may help you.
300 Insert the following lines in
302 .Bd -literal -offset indent
306 exec /usr/sbin/dconschat -rh 25;
311 exec /usr/sbin/dconschat -rh 25 -t 00-11-22-33-44-55-66-77;
327 .An Hidetoshi Shimokawa Aq simokawa@FreeBSD.org