conserver.cf(5)
NAME
conserver.cf - console configuration file for conserver(8)
DESCRIPTION
The format of the conserver.cf file is made up of named blocks of
keyword/value pairs, comments, and optional whitespace for formatting
flexibility. The block types as well as the keywords are pre-defined
and explained in the BLOCKS section. A comment is an unquoted pound-
sign to a newline. See the PARSER section for full details on
whitespace and quoting.
Let me first show you a sample block with a couple of keyword/value
pairs to make the description a bit simpler to understand.
console simple { master localhost; type exec; rw *; }
This is actually a fully functional conserver.cf file (if certain
conditions are met...and if you can list those conditions, you can
probably can skip to the BLOCKS section).
Our example is made of up of a console-block named ``simple'' with
three keyword/value pairs. What this does is define a console named
``simple'', makes the master of that console the host ``localhost'',
makes the type an exec-style console, and gives every user read/write
permission. This is the generic format of the file:
block-type block-name { keyword value; ... }
To show the addition of comments and whitespace, here is the example
reformatted (but functionally equivalent):
# define a console named "simple"
console simple {
# setting all required values...
master localhost;
type exec; # exec-style console
rw *; # allow any username
}
PARSER
The parser has six characters that it considers special. These are:
``{'', ``}'', ``;'', ``#'', ``\'', and ``"''. The first three (hereby
called tokens) define the format of the configuration blocks and are
used as word separators, the next is the comment character, and the
last two are quoting characters.
Word separation occurs when the parser encounters an unquoted token
and, in certain cases, whitespace. Whitespace is only used as a word
separator when the parser is looking for a block-type or keyword. When
it's looking for a block-name or value, whitespace is like any other
character, which allows you to embed whitespace in a block-name or
value without having to quote it. Here is an example:
default my defs { rw *; include other defs ; }
The block-type is ``default'', the block-name is ``my defs'', and the
value for the keyword ``include'' is ``other defs''. Whitespace around
tokens are ignored so you get ``other defs'' instead of ``other defs
'' as the value.
The only way to use one of the special characters as part of a block-
name or value is to quote it.
Quoting is a simple matter of prefixing a character with a backslash or
surrounding a group of characters with double-quotes. If a character
is prefixed by a backslash, the next character is a literal (so ``\\''
produces a ``\'', ``\"'' produces ``"'', ``\{'' produces a ``{'',
etc.). For double-quoted strings, all characters are literal except
for ``\"'', which embeds a double-quote.
Adding a variety of quotes to our example without changing the meaning
of things, we have:
"defa"ult my\ defs { rw *; in\clude "other defs" ; }
There is one special line the parser recognizes: a ``#include''
statement. It is of the form:
#include filename
Any whitespace around filename is ignored, but whitespace embedded
inside is preserved. Everything in filename is taken literally, so
none of the normal parser quoting applies. The #include must begin in
``column 0'' - no whitespace is allowed between it and the start of the
physical line. There is an include file depth limit of 10 to prevent
infinite recursion.
BLOCKS
access hostname|ipaddr
Define an access block for the host named hostname or using the
address ipaddr. If the value of ``*'' is used, the access block
will be applied to all conserver hosts. Access lists are used
in a first match fashion (top down), so order is important.
admin [!]username[,...]|""
Define a list of users making up the admin list for the
console server. If username matches a previously defined
group name, all members of the previous group are applied
to the admin list (with access reversed if prefixed with
a `!'). If username doesn't match a previously defined
group and username begins with `@', the name (minus the
`@') is checked against the host's group database. All
users found in the group will be granted (or denied, if
prefixed with `!') access. If username doesn't match a
previous group and doesn't begin with `@', the users will
be granted (or denied, if prefixed with `!') access. If
the null string (``""'') is used, any users previously
defined for the console servers's admin list are removed.
allowed hostname[,...]
The list of hostnames are added to the ``allowed'' list,
which grants connections from the hosts but requires
username authentication.
include accessgroup
The access lists defined using the name accessgroup are
applied to the current access block. The included access
block must be previously defined.
limited [!]username[,...]|""
Define a list of users with limited functionality on the
console server. These users will not be allowed to
suspend their connection, shift to another console, or
attach to a local command. If username matches a
previously defined group name, all members of the
previous group are applied to the admin list (with access
reversed if prefixed with a `!'). If username doesn't
match a previously defined group and username begins with
`@', the name (minus the `@') is checked against the
host's group database. All users found in the group will
be granted (or denied, if prefixed with `!') access. If
username doesn't match a previous group and doesn't begin
with `@', the users will be granted (or denied, if
prefixed with `!') access. If the null string (``""'')
is used, any users previously defined for the console
server's limited list are removed.
rejected hostname[,...]
The list of hostnames are added to the ``rejected'' list,
which rejects connections from the hosts.
trusted hostname[,...]
The list of hostnames are added to the ``trusted'' list,
which grants connections from the hosts without username
authentication.
break n
Define a break sequence where (1 <= n <= 9) or (a <= n <= z).
Break sequences are accessed via the ``^Ecln'' client escape
sequence.
confirm yes|true|on|no|false|off
Set whether or not to ask the client for confirmation
before sending the break sequence. The default is
``no''.
delay n
Set the time delay for the \d sequence to n milliseconds.
The default time delay is 250ms.
string breakseq
Assign the string breakseq to the specified slot n. A
break sequence is a simple character string with the
exception of `\' and `^':
alert
backspace
\d delay specified by the delay option.
\f form-feed
\n newline
\r carriage-return
\t tab
\v vertical-tab
\z serial break
\\ backslash
\^ circumflex
\ooo octal representation of a character (where
ooo is one to three octal digits)
\c character c
^? delete
^c control character (c is ``and''ed with 0x1f)
config hostname|ipaddr
Define a configuration block for the host named hostname or
using the address ipaddr. If the value of ``*'' is used, the
configuration block will be applied to all conserver hosts.
autocomplete yes|true|on|no|false|off
Turn the console name autocompletion feature on or off.
If autocompletion is on, a client can use any unique
leading portion of a console name when connecting to a
console. Autocompletion is on by default.
defaultaccess rejected|trusted|allowed
Set the default access permission for all hosts not
matched by an access list (see the -a command-line flag).
daemonmode yes|true|on|no|false|off
Set whether or not to become a daemon when run (see the
-d command-line flag).
initdelay number
Set the number of seconds between console
initializations. All consoles with the same host value
will be throttled as a group (those without a host value
are their own group). In other words, each console
within a group will only be initialized after number
seconds passes from the previous initialization of a
console in that group. Different throttle groups are
initialized simultaneously. One warning: since consoles
are split up and managed by seperate conserver processes,
it's possible for more than one conserver process to have
a throttle group based on a particular host value. If
this happens, each conserver process will throttle their
groups independently of the other conserver processes,
which results in a more rapid initialization (per host
value) than one might otherwise expect. If number is
zero, all consoles are initialized without delay.
logfile filename
Set the logfile to write to when in daemon mode (see the
-L command-line flag).
passwdfile filename
Set the password file location used for authentication
(see the -P command-line flag).
primaryport number|name
Set the port used by the master conserver process (see
the -p command-line flag).
redirect yes|true|on|no|false|off
Turn redirection on or off (see the -R command-line
flag).
reinitcheck number
Set the number of minutes used between reinitialization
checks (see the -O command-line flag).
secondaryport number|name
Set the base port number used by child processes (see the
-b command-line flag).
setproctitle yes|true|on|no|false|off
Set whether or not the process title shows master/group
functionality as well as the port number the process is
listening on and how many consoles it is managing. The
operating system must support the setproctitle() call.
sslcredentials filename
Set the SSL credentials file location (see the -c
command-line flag).
sslcacertificatefile filename
Load the valid CA certificates for the SSL connection
from the PEM encoded file. This option overrides the
global CA list.
sslreqclientcert yes|true|on|no|false|off
Set whether or not a certificate is required by the
client to connect. The default is ``no''.
sslrequired yes|true|on|no|false|off
Set whether or not encryption is required when talking to
clients (see the -E command-line flag).
unifiedlog filename
Set the location of the unified log to filename. See the
-U command-line flag for details.
console name
Define a console identified as name. The keywords are the same
as the default block with the following addition.
aliases name[,...]|""
Define a list of console aliases. If the null string
(``""'') is used, any aliases previously defined for the
console are removed.
default name
Define a block of defaults identified as name. If name is
``*'', the automatically applied default block is defined
(basically all consoles have an implicit ``include "*";'' at the
beginning of their definition).
baud 300|600|1800|2400|4800|9600|19200|38400|57600|115200
Assign the baud rate to the console. Only consoles of
type ``device'' will use this value.
break n
Assign the break sequence n as the default for the
console, which is used by the ``^Ecl0'' client escape
sequence.
breaklist n[,...]|""
Associate a list of break sequences referenced by n with
the console. If ``*'' is used (the default), all defined
break sequences will be available. If the null string
(``""'') is used, no sequences will be available.
device filename
Assign the serial device filename as the path to the
console. Only consoles of type ``device'' will use this
value.
devicesubst c=t[n]f[,...]|""
Perform character substitutions on the device value. A
series of replacements can be defined by specifying a
comma-separated list of c=t[n]f sequences where c is any
printable character, t specifies the replacement value, n
is a field length (optional), and f is the format string.
t can be one of the characters below, catagorized as a
string replacement or a numeric replacement, which
dictates the use of the n and f fields.
String Replacement
c console name
h host value
r replstring value
Numeric Replacement
p config port value
P calculated port value
For string replacements, if the replacement isn't at
least n characters, it will be padded with space
characters on the left. f must be `s'. For numeric
replacements, the value will be formatted to at least n
characters, padded with 0s if n begins with a 0, and
space characters otherwise. f must be either `d', `x',
`X', `a', or `A', specifying a decimal, lowercase
hexadecimal (0-9a-f), uppercase hexadecimal (0-9A-F),
lowercase alphanumeric (0-9a-z), or uppercase
alphanumeric (0-9A-Z) conversion. If the null string
(``""'') is used, no replacements will be done.
exec command|""
Assign the string command as the command to access the
console. Conserver will run the command by invoking
``/bin/sh -ce "command"''. If the null string (``""'')
is used or no exec keyword is specified, conserver will
use the command ``/bin/sh -i''. Only consoles of type
``exec'' will use this value.
execrunas [user][:group]|""
By default, the command invoked by exec is run with the
same privileges as the server. If the server is running
with root privileges, this option resets the user and/or
group of the invoked process to user and group
respectively. user may be a username or numeric uid and
group may be a group name or numeric gid. Either one is
optional. If the server is not running with root
privileges, these values are not used. If the null
string (``""'') is specified, the default of running with
the same privileges as the server is restored.
execsubst c=t[n]f[,...]|""
Perform character substitutions on the exec value. See
the devicesubst option for an explanation of the format
string. If the null string (``""'') is used, no
replacements will be done.
host hostname
Assign hostname as the host to connect to for accessing
the console. You must also set the port option for
consoles of type ``host''. Normally, only consoles of
type ``host'' and ``ipmi'' will use this value, however
if the devicesubst, execsubst, or initsubst keywords are
used in any console type, this value is used.
idlestring string|""
Assign the string that is sent to the console once the
console is idle for an idletimeout amount of time. If
the null string (``""'') is used, the string is unset and
the default is used. The string is interpreted just as a
break string is interpreted (see the break configuration
items for details) where all delays specified (via
``\d'') use the default delay time. The default string
is ``\n''.
idletimeout number[s|m|h]
Set the idle timeout of the console to number seconds.
If an `s', `m', or `h' is used after number, the
specified time is interpreted as seconds, minutes, or
hours. Set the timeout to zero to disable the idle
timeout (the default).
ipmiciphersuite number
Set the IPMI cipher suite. Syntactically valid values
are -1 (the default) and greater. Check the FreeIPMI
documentation for usable values.
ipmikg string|""
Set the BMC authentication key K_g to string. A K_g
value is a simple character string with the exception of
`\':
\\ backslash
\ooo octal representation of a character (where
ooo is one to three octal digits)
\c character c
The resulting value must be no more than 20 characters.
The null string (``""'') is the default.
impiworkaround [!]option[,...]|""
You can turn off a workaround by prefixing it with a
``!'' character. So, to turn off the integrity
workaround, you would use !integrity. The following are
valid options and their mapping to FreeIPMI settings:
activation-status SKIP_SOL_ACTIVATION_STATUS
auth-capabilites AUTHENTICATION_CAPABILITIES
channel-payload SKIP_CHANNEL_PAYLOAD_SUPPORT
checksum NO_CHECKSUM_CHECK
default DEFAULT
ignore-payload-size IGNORE_SOL_PAYLOAD_SIZE
ignore-port IGNORE_SOL_PORT
integrity NON_EMPTY_INTEGRITY_CHECK_VALUE
intel-session INTEL_2_0_SESSION
packet-sequence INCREMENT_SOL_PACKET_SEQUENCE
privilege OPEN_SESSION_PRIVILEGE
serial-alerts SERIAL_ALERTS_DEFERRED
sun-session SUN_2_0_SESSION
supermicro-session SUPERMICRO_2_0_SESSION
If no ipmiworkaround is specified, the ``default''
workaround will be used. The null string (``""'') unsets
all workarounds, including ``default''. See the FreeIPMI
documentation for details on what workarounds affect.
ipmiprivlevel user|operator|admin
Set the privilege level for the username used during IPMI
authentication. The default privilege level is
``admin''.
include default
The default block defined using the name default is
applied to the current console or default block. The
included default block must be previously defined.
initcmd command|""
Invoke command as soon as the console is brought up,
redirecting the console to stdin, stdout, and stderr of
command. The command is passed as an argument to
``/bin/sh -ce''. If the null string (``""'') is used,
the command is unset and nothing is invoked.
initrunas [user][:group]|""
By default, the command invoked by initcmd is run with
the same privileges as the server. If the server is
running with root privileges, this option resets the user
and/or group of the invoked process to user and group
respectively. user may be a username or numeric uid and
group may be a group name or numeric gid. Either one is
optional. If the server is not running with root
privileges, these values are not used. If the null
string (``""'') is specified, the default of running with
the same privileges as the server is restored.
initspinmax n|""
Set the maximum number of ``spins'' allowed for the
console to n, where 0 <= n <= 254. A console is
determined to be ``spinning'' if an attempt to initialize
the console occurs in under initspintimer seconds from
its previous initialization and this quick initialization
occurs initspinmax times in a row. If, at any point, the
time between initializations is greater than
initspintimer, the counter for reaching initspinmax
resets to zero. When a console is determined to be
``spinning'' it is forced down. If the null string
(``""'') is specified, the default of 5 is used.
initspintimer t|""
Set the number of seconds a console must be ``up'' to not
be considered ``spinning'' to t, where 0 <= t <= 254.
See initspinmax for a full description of console
``spinning.'' If the null string (``""'') is specified,
the default of 1 is used.
initsubst c=t[n]f[,...]|""
Perform character substitutions on the initcmd value.
See the devicesubst option for an explanation of the
format string. If the null string (``""'') is used, no
replacements will be done.
logfile filename|""
Assign the logfile specified by filename to the console.
Any occurrence of ``&'' in filename will be replaced with
the name of the console. If the null string (``""'') is
used, the logfile name is unset and no logging will
occur.
logfilemax number[k|m]
Enable automatic rotation of logfile once its size
exceeds number bytes. Specifying k or m interpret number
as kilobytes and megabytes. number must be at least 2048
bytes. A value of zero will turn off automatic rotation
of logfile. The logfile filename will be renamed
filename-YYYYMMDD-HHMMSS, where the extension is the
current GMT year, month, day, hour, minute, and second
(to prevent issues with clock rollbacks). File sizes are
checked every 5 minutes with an additional initial
pseudo-random delay of up to one minute (to help prevent
all processes checking all consoles simultaneously).
2.5% (minimum 100 bytes, maximum 4000 bytes) of the old
logfile is read from the end of the file. All data past
the first newline is moved (not copied) to the new
logfile so that a replay of the console works and starts
on a line boundary.
master hostname|ipaddr
Define which conserver host manages the console. The
host may be specified by hostname or using the address
ipaddr.
motd message|""
Set the "message of the day" for the console to message,
which gets displayed when a client attaches to the
console. If the null string (``""'') is used, the MOTD
is unset and no message will occur.
options [!]option[,...]|""
You can negate the option by prefixing it with a ``!''
character. So, to turn off the hupcl flag, you would use
!hupcl. The following are valid options:
ixon Enable XON/XOFF flow control on output. Only
consoles of type ``device'' or ``exec'' will
use this value. Default is ixon.
ixany Enable any character to restart output. Only
consoles of type ``device'' or ``exec'' will
use this value. Default is !ixany.
ixoff Enable XON/XOFF flow control on input. Only
consoles of type ``device'' or ``exec'' will
use this value. Default is ixoff for
consoles of type ``device'' and !ixoff for
consoles of type ``exec''.
crtscts Enable RTS/CTS (hardware) flow control. Only
consoles of type ``device'' will use this
value. Default is !crtscts.
cstopb Set two stop bits, rather than one. Only
consoles of type ``device'' will use this
value. Default is !cstopb.
hupcl Lower modem control lines after last process
closes the device (hang up). Only consoles
of type ``device'' will use this value.
Default is !hupcl.
ondemand Initialize the console when a client requests
a connection to the console. When no clients
are connected, bring the console down. The
conserver option -i will set this flag for
all consoles. Default is !ondemand.
striphigh Strip the high bit off all data coming from
this console and all clients connected to
this console before processing occurs. The
conserver option -7 will set this flag for
all consoles. Default is !striphigh.
reinitoncc Automatically reinitialize (``bring up'') a
downed console when a client connects.
Without this option, a client will be
attached to the downed console and will need
to manually reinitialize the console with an
escape sequence. The conserver option -o
will set this flag for all consoles. Default
is !reinitoncc.
autoreinit Allow this console to be automatically
reinitialized if it unexpectedly goes down.
If the console doesn't come back up, it is
retried every minute. A console of type
``exec'' that exits with a zero exit status
is automatically reinitialized regardless of
this setting. The conserver option -F will
unset this flag for all consoles. Default is
autoreinit.
unloved Enable the sending of this console's output
(prefixed with its name) to the daemon's
stdout (or the logfile if in daemon mode)
when no clients are connected to the console.
The conserver option -u will set this flag
for all consoles. Default is !unloved.
login Allow users to log into this console. If
logins are not allowed, conserver will send a
generic message to the client saying so and
terminate the connection. You can override
the generic message by setting the motd
message. Default is login.
parity even|mark|none|odd|space
Set the parity option for the console. Only consoles of
type ``device'' will use this value.
password password|""
Use password during IPMI authentication. If the null
string (``""'') is used (the default), no password will
be used.
port number|name
Set the port used to access the console. The port may be
specified as a number or a name. A name will cause a
getservbyname(3) call to look up the port number. The
port, portbase, and portinc values are all used to
calculate the final port number to connect to. The
formula used is finalport = portbase + portinc * port.
By using proper values in the formula, you can reference
ports on a terminal server by their physical numbering of
0..n or 1..n (depending on if you like zero-based or one-
based numbering). Warning: you can generate a -1 value
with this formula, which will become a very high numbered
positive value (since things are stored unsigned). You
must also set the host option as well. Normally, only
consoles of type ``host'' will use this value, however if
the devicesubst, execsubst, or initsubst keywords are
used in any console type, this value is used.
portbase number
Set the base value for the port calculation formula.
number must be 0 or greater. The default is zero. See
port for the details of the formula.
portinc number
Set the increment value for the port calculation formula.
number must be 0 or greater. The default is one. See
port for the details of the formula.
protocol telnet|raw
Set the protocol used to send and receive data from the
console. If raw is used, all data is sent ``as is'',
unprotected by any protocol specification. If telnet is
used (which is the default), data is encapsulated in the
telnet protocol. The striphigh console option still
applies when data is read by the server, and if enabled,
can impact the encapsulation process.
replstring string
A generic replacement string that can be used by the
devicesubst, execsubst, and initsubst keywords.
ro [!]username[,...]|""
Define a list of users making up the read-only access
list for the console. If username matches a previously
defined group name, all members of the previous group are
applied to the read-only access list (with access
reversed if prefixed with a `!'). If username doesn't
match a previously defined group and username begins with
`@', the name (minus the `@') is checked against the
host's group database. All users found in the group will
be granted (or denied, if prefixed with `!') read-only
access. If username doesn't match a previous group and
doesn't begin with `@', the users will be granted (or
denied, if prefixed with `!') read-only access. If the
null string (``""'') is used, any users previously
defined for the console's read-only list are removed.
rw [!]username[,...]|""
Define a list of users making up the read-write access
list for the console. If username matches a previously
defined group name, all members of the previous group are
applied to the read-write access list (with access
reversed if prefixed with a `!'). If username doesn't
match a previously defined group and username begins with
`@', the name (minus the `@') is checked against the
host's group database. All users found in the group will
be granted (or denied, if prefixed with `!') read-write
access. If username doesn't match a previous group and
doesn't begin with `@', the users will be granted (or
denied, if prefixed with `!') read-write access. If the
null string (``""'') is used, any users previously
defined for the console's read-write list are removed.
tasklist c[,...]|""
Associate a list of tasks referenced by c with the
console. If ``*'' is used (the default), all defined
tasks will be available. If the null string (``""'') is
used, no tasks will be available.
timestamp [number[m|h|d|l]][a][b]|""
Specifies the time between timestamps applied to the
console log file and whether to log read/write connection
actions. The timestamps look like ``[-- MARK -- Mon Jan
25 14:46:56 1999]''. The `m', `h', and `d' tags specify
``minutes'' (the default), ``hours'', and ``days''. The
`l' tag specifies ``lines'' and will cause timestamps of
the form ``[Mon Jan 25 14:46:56 PST 1999]'' to be placed
every number lines (a newline character signifies a new
line). So, ``5h'' specifies every five hours and ``2l''
specifies every two lines. An `a' can be specified to
add logs of ``attached'', ``detached'', and ``bumped''
actions, including the user's name and the host from
which the client connection was made. A `b' can be
specified to add logging of break sequences sent to the
console.
type device|ipmi|exec|host|noop|uds
Set the type of console. A type of ``device'' should be
used for local serial ports (also set the device value).
A type of ``ipmi'' should be used for IPMI serial over
LAN consoles (also set the host value and possibly the
username, password, and ipmi* values). A type of
``exec'' should be used for command invocations (perhaps
also set the exec value). A type of ``host'' should be
used for terminal servers and other TCP socket-based
interaction (also set the host and port values). A type
of ``noop'' should be used as a placeholder - it does
nothing, ignores any logfile value and forces the
!nologin option (so you might want to set the motd
value). A type of ``uds'' should be used for Unix domain
sockets (also set the uds option).
uds filename
Assign the Unix domain socket filename as the path to the
console. Only consoles of type ``uds'' will use this
value.
udssubst c=t[n]f[,...]|""
Perform character substitutions on the uds value. See
the devicesubst option for an explanation of the format
string. If the null string (``""'') is used, no
replacements will be done.
username username|""
Use username during IPMI authentication. If the null
string (``""'') is used (the default), the ``null'' user
will be used.
group name
Define a user group identified as name.
users [!]username[,...]|""
Define a list of users making up the group name. If
username matches a previously defined group name, all
members of the previous group are applied to the current
group (with access reversed if prefixed with a `!'). If
username doesn't match a previously defined group and
username begins with `@', the name (minus the `@') is
checked against the host's group database. All users
found in the group will be recorded with (or without, if
prefixed with `!') access. If username doesn't match a
previous group and doesn't begin with `@', the users will
be recorded with (or without, if prefixed with `!')
access. If the null string (``""'') is used, any users
previously defined for this group are removed.
task c
Define a task where c is a lowercase alphanumeric (0-9a-z).
Tasks are invoked via the ``^Ec!c'' client escape sequence.
cmd command|""
Invoke command on the server when instructed by the
client. All file descriptors are closed, except for
stderr (which is inherited from the server). The command
is passed as an argument to ``/bin/sh -ce'' and is a
``fire and forget'' methodology (you need to check logs
for any issues). If the null string (``""'') is used,
the entire task definition is ignored.
confirm yes|true|on|no|false|off
Set whether or not to ask the client for confirmation
before invoking the task. The default is ``no''.
description string
Set a description for the task. When a client lists
tasks, string will be printed instead of the command
defined above. If the null string (``""'') is used, the
command defined above will be printed.
runas [user][:group]|""
By default, the command invoked by cmd is run with the
same privileges as the server. If the server is running
with root privileges, this option resets the user and/or
group of the invoked process to user and group
respectively. user may be a username or numeric uid and
group may be a group name or numeric gid. Either one is
optional. If the server is not running with root
privileges, these values are not used. If the null
string (``""'') is specified, the default of running with
the same privileges as the server is restored.
subst c=t[n]f[,...]|""
Perform character substitutions on the cmd value. See
the devicesubst option for an explanation of the format
string. If the null string (``""'') is used, no
replacements will be done.
AUTHORS
Bryan Stansell, conserver.com
SEE ALSO
console(1), conserver.passwd(5), conserver(8)
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