Console
is used to manipulate console terminals remotely or to poll running
conserver(8) daemons for status information.
In the first form above,
console
asks the user's password before
granting interactive access to a console (on a non-trusted system),
since such a session may provide single-user access.
Only as much of the console name as is required to
identify it uniquely to the server is required.
For non-interactive options,
console
outputs only the requested information and exits.
Console
knows only of a primary
conserver
host
(see the -M option below),
to which it initially connects.
In a multi-server environment, the primary server may refer
the client to a different server handling the requested console,
or it will provide a list of all servers if required
(as when
console
is invoked with the
`-r'
option).
Console
then opens connections to the appropriate server(s).
It is not necessary for the user of
console
to know which server manages which consoles,
as long as
console
knows a valid primary server
and all available consoles are listed in the primary server's
configuration file.
OPTIONS
Options may be given as separate arguments (e.g., -v -w)
or clustered (e.g., -vw).
Options and their arguments may be separated by optional white space.
Option arguments containing spaces or other characters special to the shell
must be quoted.
-7
Strip the high bit off of all data received,
whether from user input or from the server,
before any processing occurs.
Disallows escape sequence characters with the high bit set.
-a
Access a console with a two-way (read-write) connection (this is the default).
The connection is dropped to spy mode if someone else is attached read-write.
-bmessage
Broadcast a message to all users connected to the console server.
-D
Enable debugging output.
-eesc
Set the initial two-character escape sequence to
those represented by esc.
Any of the forms output by cat(1)'s -v option
are accepted. The default value is ``^Ec''.
-f
Same as -a except it will force any existing connection into spy mode.
-G
Request a raw connection to the group control virtual console;
this is only useful for learning the protocol used by the
interactive sequence.
-h
Display a brief help message.
-i
Display information in a machine-parseable format (see below for the details).
-luser
Set the login name used for authentication to user.
By default, console uses $USER if its uid matches the user's real uid,
or $LOGNAME if its uid matches the user's real uid,
or else the name associated with the user's real uid.
-Mmach
The console client program polls mach as the primary server,
rather than the default set at compile time (typically ``console'').
The default mach may be changed at compile time using the
--with-master option.
-pport
Set the port to connect to. This may be either a port number
or a service name. The default port may be changed at compile time
using the --with-port option.
-P
Display the pid of the master daemon process on each server.
-q
The console client connects to each server to request that the
server daemon quit (shut down). The root password of the host(s)
running conserver is required unless the local host is listed as
``trusted'' in the conserver.cf file; in that case, just
press <return>.
-Q
Same as -q but just acts on the primary server.
-r
Display daemon versions. The console client connects to each
server to request its version information.
-R
Same as -r but just acts on the primary server.
-s
Request a read-only (spy mode) connection.
In this mode all the escape sequences (below) work, or report errors,
but all other keyboard input is discarded.
-u
Show a list of all consoles with status (`up' or `down')
and attached users (user@host if attached read-write,
`<spies>' if only users in spy mode, or `<none>').
-v
Be more verbose when building the connection(s).
Use this option in combination with any of `show' options (below)
for added benefit.
-V
Output the version and settings of the console client program
and then exit.
-w
Show a list of all who are currently connected to consoles,
including the hostnames where the console connections originate
and the idle times. This is useful to see if anybody is actively
using the console system if it becomes necessary to shut down
conserver.
-x
Show a list of consoles and devices.
The -A, -F, or -S options have the same effect as
their lower-case variants.
In addition, they each request the last 20 lines of the console output after
making the connection (as if `^Ecr' were typed).
The -i option outputs information regarding each console in
ten colon-separated fields.
name
The name of the console.
hostname,pid,socket
The hostname, pid, and socket number of the child process managing
the console.
type
The type of console. Values will be a `/' for a local device, `|' for
a command, or `!' for a remote port.
console-details
The details regarding the console. The values here (all comma seperated)
depend on the type of the console. Local devices will have values of
the device file, baud rate, and file descriptor for the device.
Commands will have values of the command, the command's pid, the
pseudo-tty, and file descriptor for the pseudo-tty.
Remote ports will have values of the remote hostname, remote port number,
and file descriptor for the socket connection.
users-list
The details of each user connected to the console. The details for each
user are an `@' seperated list of `w', `r', or `s' (for read-write, read-only,
or suspended), username, hostname the user is on, and the user's idle time.
Each user bundle is seperated by commas.
state
The state of the console. Values with either be ``up'' or ``down''.
perm
This value will either be ``rw'' or ``ro''. It will only be ``ro'' if
the console is a local device (`/' type) and the permissions are such
that the server can open the file for read, but not write.
logfile-details
The details regarding the logging for the console. The comma seperated
values will be the logfile, ``log'' or ``nolog'' (if logging is on
or not - toggled via ^EcL), ``act'' or ``noact'' (if activity logging is
enabled or not - the `a' timestamp option), the timestamp interval, and
the file descriptor of the logfile.
break
The default break sequence used for the console.
reup
If the console is currently down and the automatic reconnection code
is at work, it will have the value of ``autoup'', otherwise it
will be ``noautoup''.
ESCAPE SEQUENCES
The connection can be controlled by a two-character escape sequence, followed
by a command. The default escape sequence is ``control-E c''
(octal 005 143).
(The escape sequences are actually processed by the server; see the
conserver(8)
man page for more information.)
Commands are:
a
attach read-write if nobody already is
b
send broadcast message to all users on this console
c
toggle flow control (don't do this)
d
down the current console
ecc
change the escape sequence to the next two characters
f
forcibly attach read-write
g
group info
L
toggle logging on/off
l?
list the break sequences available
l0
send the break sequence associated with this console
l1-9
send the specific break sequence
o
close (if open) and reopen the line (to clear errors (silo overflows))
and the log file
p
replay the last 60 lines of output
r
replay the last 20 lines of output
s
switch to spy mode (read-only)
u
show status of hosts/users in this group
v
show the version of the group server
w
who is using this console
x
examine this group's devices and modes
z
suspend this connection
?
display list of commands
^M (return)
continue, ignore the escape sequence
^R (ctrl-R)
replay the last line only
\\fIooo
send character having octal code ooo
(must specify three octal digits)
.
disconnect
If any other character is hit after the escape sequence, all three characters
will be discarded.
Note that a line break or a down command
can only be sent from a full two-way attachment.
To send the escape sequence through the connection one must redefine
the outer escape sequence, or use ^Ec\ooo to send the
first escape character before typing the second character directly.
In the -u output, the login ``<none>'' indicates no one is
viewing that console, and the login ``<spies>'' indicates that
no one has a full two-way attachment. When no one is attached to
a console its output is cloned to the stdout of the server process
if conserver was started with the -u option.
The <none> indicates no one is viewing dumb or mentor,
the <spies> indicates only read-only connections exist for tyro,
and
other login@host entries indicate users attached read-write to
sage and expert.
The third column is the idle time of the user.
Either hours:minutes or number of days is displayed.
console -e ``^[1'' lv426
Requests a connection to the host ``lv426'' with the escape characters
set to ``escape one''.
BUGS
All client/server traffic (including root and user passwords) is
passed ``in the clear''. Extreme care should be taken to insure no one
is ``snooping'' this private data. One day the traffic will be encrypted.
It is possible to create a loop of console connections, with ugly results.
Never run console from within a console connection (unless you set each
escape sequence differently).
The -G option doesn't help to explain how connections get built.
AUTHORS
Thomas A. Fine, Ohio State Computer Science
Kevin Braunsdorf, Purdue University Computing Center
Bryan Stansell, conserver.com