1CSSH(1) User Contributed Perl Documentation CSSH(1)
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6 cssh (crsh) - Cluster administration tool
7
9 cssh [options] [[user@]<server>⎪<tag>] [...]
10 crsh [options] [[user@]<server>⎪<tag>] [...]
11 cssh [options] [[user@]<server>[:port]⎪<tag>] [...]
12 crsh [options] [[user@]<server>[:port]⎪<tag>] [...]
13
15 The command opens an administration console and an xterm to all speci‐
16 fied hosts. Any text typed into the administration console is repli‐
17 cated to all windows. All windows may also be typed into directly.
18 This tool is intended for (but not limited to) cluster administration
20 where the same configuration or commands must be run on each node
21 within the cluster. Performing these commands all at once via this
22 tool ensures all nodes are kept in sync.
23 Connections are opened via ssh so a correctly installed and configured
25 ssh installation is required. If, however, the program is called by
26 "crsh" then the rsh protocol is used (and the communications channel is
27 insecure).
28 Extra caution should be taken when editing system files such as
30 /etc/inet/hosts as lines may not necessarily be in the same order.
31 Assuming line 5 is the same across all servers and modifying that is
32 dangerous. Better to search for the specific line to be changed and
33 double-check before changes are committed.
34 Further Notes
36 · The dotted line on any sub-menu is a tear-off, i.e. click on it and
38 the sub-menu is turned into its own window.
39 · Unchecking a hostname on the Hosts sub-menu will unplug the host
41 from the cluster control window, so any text typed into the console
42 is not sent to that host. Re-selecting it will plug it back in.
43 · If the code is called as crsh instead of cssh (i.e. a symlink
45 called crsh points to the cssh file or the file is renamed) rsh is
46 used as the communications protocol instead of ssh.
47 · Starting the utility will be much faster with a configuration file
49 (as this prevents searching for required files). Generate one con‐
50 taining all default entries with:
51 "cssh -u > $HOME/.csshrc"
53 · When using cssh on a large number of systems to connect back to a
55 single system (e.g. you issue a command to the cluster to scp a
56 file from a given location) and when these connections require
57 authentication (i.e. you are going to authenticate with a pass‐
58 word), the sshd daemon at that location may refuse connects after
59 the number specified by MaxStartups in sshd_config is exceeded.
60 (If this value is not set, it defaults to 10.) This is expected
61 behavior; sshd uses this mechanism to prevent DoS attacks from
62 unauthenticated sources. Please tune sshd_config and reload the
63 SSH daemon, or consider using the ~/.ssh/authorized_keys mechanism
64 for authentication if you encounter this problem.
65 · If client windows fail to open, try running "cssh -d <single host
67 name>". This will output a command to run which will test the
68 method used by cssh to open client windows. If you copy-and-paste
69 this command into a window and it fails, this is the issue. It is
70 most likely due to the "-xrm" option which enables "AllowSendE‐
71 vents" in the terminal. Some terminal do not require this option,
72 other terminals have another method for enabling it. See your ter‐
73 minal documention for further information.
74
76 Some of these options may also be defined within the configuration
77 file. Default options are shown as appropriate.
78 -h⎪-?
80 Show basic help text, and exit
81 -H Show full help test (the man page), and exit
83 -v Show version information and exit
85 -d Enable basic debugging mode (can be combined with -D)
87 -D Enable extended debugging mode (can be combined with -d)
89 -q⎪-Q
91 Enable⎪Disable automatically quiting after the last client window
92 has closed (overriding the config file)
93 -u Output configuration in the format used by the $HOME/.csshrc file
95 -g⎪-G
97 Enable⎪Disable window tiling (overriding the config file)
98 -c <file>
100 Use supplied file as additional cluster file (see also "FILES")
101 -l $LOGNAME
103 Specify the default username to use for connections (if different
104 from the currently logged in user). NOTE: will be overridden by
105 <user>@<host>
106 -T "CSSH"
108 Specify the initial part of the title used in the console and
109 client windows
110 -o "-x -o ConnectTimeout=10" - for ssh connections
112 -o "" - for rsh connections
113 Specify arguments to be passed to ssh or rsh when making the con‐
114 nection.
115 NOTE: any "generic" change to the method (i.e. specifying the ssh
117 port to use) should be done in the medium's own config file (see
118 ssh_config and $HOME/.ssh/config).
119 -t ""
121 Specify arguments to be passed to terminals being used
122 -i Ignore errors from unresolvable host names (i.e. because the name
124 is an alias within an ssh config file or similar) (see also
125 "ignore_host_errors" in "FILES")
126 -e [user@]<hostname>[:port]
128 Display and evaluate the terminal and connection arguments so dis‐
129 play any potential errors. The <hostname> is required to aid the
130 evaluation.
131
133 The following arguments are support:
134 [user@]<hostname>[:port] ...
136 Open an xterm to the given hostname and connect to the administra‐
137 tion console. An optional port number can be used if sshd is not
138 listening on standard port (e.g not listening on port 22) and
139 ssh_config cannot be used.
140 <tag> ...
142 Open a series of xterms defined by <tag> within either /etc/clus‐
143 ters or $HOME/.csshrc (see "FILES").
144
146 The following key shortcuts are available within the console window,
147 and all of them may be changed via the configuration files.
148 Control-q
150 Quit the program and close all connections and windows
151 Control-+
153 Open the Add Host dialogue box
154 Alt-n
156 Paste in the correct client name to all clients, i.e.
157 "scp /etc/hosts server:files/<Alt-n>.hosts"
159 would replace the <Alt-n> with the client's name in all the client
161 windows
162 Alt-r
164 Retile all the client windows
165
167 /etc/clusters
168 This file contains a list of tags to server names mappings. When
169 any name is used on the command line it is checked to see if it is
170 a tag in /etc/clusters (or the .csshrc file, or any additional
171 cluster file specified by -c). If it is a tag, then the tag is
172 replaced with the list of servers from the file. The file is for‐
173 mated as follows:
174 <tag> [user@]<server> [user@]<server> [...]
176 i.e.
178 # List of servers in live
180 live admin1@server1 admin2@server2 server3 server4
181 All standard comments and blank lines are ignored. Tags may be
183 nested, but be aware of recursive tags.
184 Clusters may also be specified within the user's .csshrc file, as
186 documented below.
187 /etc/csshrc & $HOME/.csshrc
189 This file contains configuration overrides - the defaults are as
190 marked. Default options are overwritten first by the global file,
191 and then by the user file.
192 always_tile = yes
194 Setting to anything other than "yes" does not perform window
195 tiling (see also -G).
196 auto_quit = yes
198 Automatically quit after the last client window closes. Set to
199 anything other than "yes" to disable. Can be overridden by
200 "-Q" on the command line.
201 comms = ssh
203 Sets the default communication method (initially taken from the
204 name of program, but can be overridden here).
205 clusters = <blank>
207 Define a number of cluster tags in addition to (or to replace)
208 tags defined in the /etc/clusters file. The format is:
209 clusters = <tag1> <tag2> <tag3>
211 <tag1> = host1 host2 host3
212 <tag2> = user@host4 user@host5 host6
213 <tag3> = <tag1> <tag2>
214 As with the /etc/clusters file, be sure not to create recur‐
216 sivly nested tags.
217 console_position = <null>
219 Set the initial position of the console - if empty then let the
220 window manager decide. Format is '+<x>+<y>', i.e. '+0+0' is
221 top left hand corner of the screen, '+0-70' is bottom left hand
222 side of screen (more or less).
223 ssh_args = "-x -o ConnectTimeout=10"
225 rsh_args = <blank>
226 Sets any arguments to be used with the communication method
227 (defaults to ssh arguments).
228 NOTE: The given defaults are based on OpenSSH, not commercial
230 ssh software.
231 NOTE: Any "generic" change to the method (i.e. specifying the
233 ssh port to use) should be done in the medium's own config file
234 (see ssh_config and $HOME/.ssh/config).
235 ignore_host_errors = "no"
237 If set to "yes", ignore errors from host names that cannot be
238 resolved and attempt to connect anyway (i.e. because they are
239 aliased in an ssh config file) - see also "-i"
240 key_addhost = Control-plus
242 Default key sequence to open AddHost menu. See below notes on
243 shortcuts.
244 key_clientname = Alt-n
246 Default key sequence to send cssh client names to client. See
247 below notes on shortcuts.
248 key_quit = Control-q
250 Default key sequence to quit the program (will terminate all
251 open windows). See below notes on shortcuts.
252 key_retilehosts = Alt-r
254 Default key sequence to retile host windows. See below notes
255 on shortcuts.
256 key_paste = Control-v
258 Default key sequence to paste text into the console window.
259 See below notes on shortcuts.
260 mouse_paste = Button-2 (middle mouse button)
262 Default key sequence to paste text into the console window
263 using the mouse. See below notes on shortcuts.
264 screen_reserve_top = 25
266 screen_reserve_bottom = 30
267 screen_reserve_left = 0
268 screen_reserve_right = 0
269 Number of pixels from the screen side to reserve when calculat‐
270 ing screen geometry for tiling. Setting this to something like
271 50 will help keep cssh from positioning windows over your win‐
272 dow manager's menu bar if it draws one at that side of the
273 screen.
274 ssh = /path/to/ssh
276 rsh = /path/to/rsh
277 Depending on the value of comms, set the path of the communica‐
278 tion binary.
279 terminal = /path/to/terminal
281 Path to the x-windows terminal used for the client.
282 terminal_args = <blank>
284 Arguments to use when opening terminal windows. Otherwise
285 takes defaults from $HOME/.Xdefaults or $<$HOME/.Xresources>
286 file.
287 terminal_font = 6x13
289 Font to use in the terminal windows. Use standard X font nota‐
290 tion.
291 terminal_reserve_top = 0
293 terminal_reserve_bottom = 0
294 terminal_reserve_left = 0
295 terminal_reserve_right = 0
296 Number of pixels from the terminal side to reserve when calcu‐
297 lating screen geometry for tiling. Setting these will help
298 keep cssh from positioning windows over your scroll and title
299 bars
300 terminal_size = 80x24
302 Initial size of terminals to use (note: the number of lines
303 (24) will be decreased when resizing terminals for tiling, not
304 the number of characters (80))
305 terminal_title_opt = -T
307 Option used with "terminal" to set the title of the window
308 terminal_allow_send_events = -xrm 'XTerm.VT100.allowSendE‐
310 vents:true'
311 Option required by the terminal to allow XSendEvents to be
312 received
313 title = cssh
315 Title of windows to use for both the console and terminals.
316 use_hotkeys = yes
318 Setting to anything other than "yes" will disable all hotkeys.
319 user = $LOGNAME
321 Sets the default user for running commands on clients.
322 window_tiling = yes
324 Perform window tiling (set to "no" to disable)
325 window_tiling_direction = right
327 Direction to tile windows, where "right" means starting top
328 left and moving right and then down, and anything else means
329 starting bottom right and moving left and then up
330 NOTE: The key shortcut modifiers must be in the form "Control",
332 "Alt", or "Shift", i.e. with the first letter capitalised and the
333 rest lower case. Keys may also be disabled individually by setting
334 to the work "null".
335
337 Duncan Ferguson
338
340 clusterssh is distributed under the GNU public license. See the file
341 LICENSE for details.
342 A web site for comments, requests, bug reports and bug fixes/patches is
344 available at <http://clusterssh.sourceforge.net/>
345
347 Swapping virtual desktops can can a redraw of all the terminal windows.
348 This is due to a lack of distinction within Tk between switching desk‐
349 tops and minimising/maximising windows. Until Tk can tell the differ‐
350 ence between the two events, there is no fix (apart from rewriting
351 everything directly in X)
352
354 · If you have issues running cssh, first try:
355 "cssh -e [user@]<hostname>[:port]"
357 This performs two tests to confirm cssh is able to work properly with
359 the settings provided within the .csshrc file (or internal defaults).
360 1. test the terminal window works with the options provided
362 2. test ssh works to a host with the configured arguments
364 Configuration options to watch for in ssh are
366 - Doesnt understand "-o ConnectTimeout=10" - remove the option
368 in the F<.csshrc> file
369 - OpenSSH-3.8 using untrusted ssh tunnels - use "-Y" instead of "-X"
371 or use "ForwardX11Trusted yes' in ssh_config (if you change the
372 default ssh options from -x to -X)
373 · If you require support, please run the following commands and post it
375 on the web site in the support/problems forum:
376 "perl -V"
378 "perl -MTk -e 'print $Tk::VERSION,$/'"
380 "perl -MX11::Protocol -e 'print $X11::Protocol::VERSION,$/'"
382 "cat /etc/csshrc $HOME/.csshrc"
384 · Use the debug switches (-d, -D, or -dD) will turn on debugging out‐
386 put. However, please only use this option with one host at a time,
387 i.e. "cssh -d <host>" due to the amount of output produced (in both
388 main and child windows).
389
391 <http://clusterssh.sourceforge.net/>, ssh, Tk::overview, X11::Protocol,
392 perl
393perl v5.8.8 2006-07-24 CSSH(1)