分类： LINUX
2010-01-04 13:17:58
SUDO(8) MAINTENANCE COMMANDS SUDO(8)
NAME
sudo, sudoedit - execute a command as another user
SYNOPSIS
sudo -h | -K | -k | -L | -l | -V | -v
sudo [-bEHPS] [-a auth_type] [-c class|-] [-p prompt] [-u username|#uid] [VAR=value] {-i | -s | command}
sudoedit [-S] [-a auth_type] [-c class|-] [-p prompt] [-u username|#uid] file ...
DESCRIPTION
sudo allows a permitted user to execute a command as the superuser or another user, as specified in the
sudoers file. The real and effective uid and gid are set to match those of the target user as specified
in the passwd file and the group vector is initialized based on the group file (unless the -P option was
specified). If the invoking user is root or if the target user is the same as the invoking user, no
password is required. Otherwise, sudo requires that users authenticate themselves with a password by
default (NOTE: in the default configuration this is the user's password, not the root password). Once a
user has been authenticated, a timestamp is updated and the user may then use sudo without a password for
a short period of time (15 minutes unless overridden in sudoers).
When invoked as sudoedit, the -e option (described below), is implied.
sudo determines who is an authorized user by consulting the file /etc/sudoers. By giving sudo the -v
flag, a user can update the time stamp without running a command. The password prompt itself will also
time out if the user's password is not entered within 0 minutes (unless overridden via sudoers).
If a user who is not listed in the sudoers file tries to run a command via sudo, mail is sent to the
proper authorities, as defined at configure time or in the sudoers file (defaults to root). Note that
the mail will not be sent if an unauthorized user tries to run sudo with the -l or -v flags. This allows
users to determine for themselves whether or not they are allowed to use sudo.
If sudo is run by root and the SUDO_USER environment variable is set, sudo will use this value to deter-
mine who the actual user is. This can be used by a user to log commands through sudo even when a root
shell has been invoked. It also allows the -e flag to remain useful even when being run via a sudo-run
script or program. Note however, that the sudoers lookup is still done for root, not the user specified
by SUDO_USER.
sudo can log both successful and unsuccessful attempts (as well as errors) to syslog(3), a log file, or
both. By default sudo will log via syslog(3) but this is changeable at configure time or via the sudoers
file.
OPTIONS
sudo accepts the following command line options:
……
-b The -b (background) option tells sudo to run the given command in the background. Note that if you
use the -b option you cannot use shell job control to manipulate the process.
……
-E The -E (preserve environment) option will override the env_reset option in sudoers(5)). It is only
available when either the matching command has the SETENV tag or the setenv option is set in sudo-
ers(5).
-e The -e (edit) option indicates that, instead of running a command, the user wishes to edit one or
more files. In lieu of a command, the string "sudoedit" is used when consulting the sudoers file.
If the user is authorized by sudoers the following steps are taken:
1. Temporary copies are made of the files to be edited with the owner set to the invoking user.
2. The editor specified by the VISUAL or EDITOR environment variables is run to edit the temporary
files. If neither VISUAL nor EDITOR are set, the program listed in the editor sudoers variable
is used.
3. If they have been modified, the temporary files are copied back to their original location and
the temporary versions are removed.
If the specified file does not exist, it will be created. Note that unlike most commands run by
sudo, the editor is run with the invoking user's environment unmodified. If, for some reason, sudo
is unable to update a file with its edited version, the user will receive a warning and the edited
copy will remain in a temporary file.
-H The -H (HOME) option sets the HOME environment variable to the homedir of the target user (root by
default) as specified in passwd(5). By default, sudo does not modify HOME (see set_home and
always_set_home in sudoers(5)).
-h The -h (help) option causes sudo to print a usage message and exit.
……
-L The -L (list defaults) option will list out the parameters that may be set in a Defaults line along
with a short description for each. This option is useful in conjunction with grep(1).
-l The -l (list) option will list out the allowed (and forbidden) commands for the invoking user on the
current host.
-P The -P (preserve group vector) option causes sudo to preserve the invoking user's group vector unal-
tered. By default, sudo will initialize the group vector to the list of groups the target user is
in. The real and effective group IDs, however, are still set to match the target user.
-p The -p (prompt) option allows you to override the default password prompt and use a custom one. The
following percent (`%') escapes are supported:
%H expanded to the local hostname including the domain name (on if the machine's hostname is fully
qualified or the fqdn sudoers option is set)
%h expanded to the local hostname without the domain name
%U expanded to the login name of the user the command will be run as (defaults to root)
%u expanded to the invoking user's login name
%% two consecutive % characters are collapsed into a single % character
……
-S The -S (stdin) option causes sudo to read the password from the standard input instead of the termi-
nal device.
-s The -s (shell) option runs the shell specified by the SHELL environment variable if it is set or the
shell as specified in passwd(5).
……
SUDOERS(5) MAINTENANCE COMMANDS SUDOERS(5)
NAME
sudoers - list of which users may execute what
DESCRIPTION
The sudoers file is composed of two types of entries: aliases (basically variables) and user specifica-
tions (which specify who may run what).
When multiple entries match for a user, they are applied in order. Where there are multiple matches, the
last match is used (which is not necessarily the most specific match).
The sudoers grammar will be described below in Extended Backus-Naur Form (EBNF). Don't despair if you
don't know what EBNF is; it is fairly simple, and the definitions below are annotated.
Quick guide to EBNF
EBNF is a concise and exact way of describing the grammar of a language. Each EBNF definition is made up
of production rules. E.g.,
symbol ::= definition | alternate1 | alternate2 ... (::=表示其左边的内容可用右边的内容来替换)
Each production rule references others and thus makes up a grammar for the language. EBNF also contains
the following operators, which many readers will recognize from regular expressions. Do not, however,
confuse them with "wildcard" characters(通配符), which have different meanings.
? Means that the preceding symbol (or group of symbols) is optional. That is, it may appear once or
not at all.
* Means that the preceding symbol (or group of symbols) may appear zero or more times.
+ Means that the preceding symbol (or group of symbols) may appear one or more times.
Parentheses may be used to group symbols together. For clarity, we will use single quotes ('') to desig-
nate what is a verbatim character string (as opposed to a symbol name).
Aliases
There are four kinds of aliases: User_Alias, Runas_Alias(Runas stand for Run as), Host_Alias and Cmnd_Alias(Cmnd stand for Command).
Alias ::= 'User_Alias' User_Alias (':' User_Alias)* |
'Runas_Alias' Runas_Alias (':' Runas_Alias)* |
'Host_Alias' Host_Alias (':' Host_Alias)* |
'Cmnd_Alias' Cmnd_Alias (':' Cmnd_Alias)*
User_Alias ::= NAME '=' User_List
Runas_Alias ::= NAME '=' Runas_List
Host_Alias ::= NAME '=' Host_List
Cmnd_Alias ::= NAME '=' Cmnd_List
NAME ::= [A-Z]([A-Z][0-9]_)*
Each alias definition is of the form
Alias_Type NAME = item1, item2, ...
where Alias_Type is one of User_Alias, Runas_Alias, Host_Alias, or Cmnd_Alias. A NAME is a string of
uppercase letters, numbers, and underscore characters ('_'). A NAME must start with an uppercase letter.
It is possible to put several alias definitions of the same type on a single line, joined by a colon
(':'). E.g.,
Alias_Type NAME = item1, item2, item3 : NAME = item4, item5
The definitions of what constitutes a valid alias member follow.
User_List ::= User |
User ',' User_List
User ::= '!'* username |
'!'* '%'group |
'!'* '+'netgroup |
'!'* User_Alias
A User_List is made up of one or more usernames, system groups (prefixed with '%'), netgroups (prefixed
with '+') and other aliases. Each list item may be prefixed with one or more '!' operators. An odd num-
ber of '!' operators negate the value of the item; an even number just cancel each other out.
Runas_List ::= Runas_User |
Runas_User ',' Runas_List
Runas_User ::= '!'* username |
'!'* '#'uid |
'!'* '%'group |
'!'* +netgroup |
'!'* Runas_Alias
A Runas_List is similar to a User_List except that it can also contain uids (prefixed with '#') and
instead of User_Aliases it can contain Runas_Aliases. Note that usernames and groups are matched as
strings. In other words, two users (groups) with the same uid (gid) are considered to be distinct. If
you wish to match all usernames with the same uid (e.g. root and toor), you can use a uid instead (#0 in
the example given).
Host_List ::= Host |
Host ',' Host_List
Host ::= '!'* hostname |
'!'* ip_addr |
'!'* network(/netmask)? |
'!'* '+'netgroup |
'!'* Host_Alias
A Host_List is made up of one or more hostnames, IP addresses, network numbers, netgroups (prefixed with
'+') and other aliases. Again, the value of an item may be negated with the '!' operator. If you do not
specify a netmask along with the network number, sudo will query each of the local host's network inter-
faces and, if the network number corresponds to one of the hosts's network interfaces, the corresponding
netmask will be used. The netmask may be specified either in standard IP address notation
(e.g. 255.255.255.0 or ffff:ffff:ffff:ffff::), or CIDR notation (number of bits, e.g. 24 or 64). A host-
name may include shell-style wildcards (see the Wildcards section below), but unless the hostname command
on your machine returns the fully qualified hostname, you'll need to use the fqdn option for wildcards to
be useful.
Cmnd_List ::= Cmnd |
Cmnd ',' Cmnd_List
commandname ::= filename |
filename args |
filename '""'
Cmnd ::= '!'* commandname |
'!'* directory |
'!'* "sudoedit" |
'!'* Cmnd_Alias
A Cmnd_List is a list of one or more commandnames, directories, and other aliases. A commandname is a
fully qualified filename which may include shell-style wildcards (see the Wildcards section below). A
simple filename allows the user to run the command with any arguments he/she wishes. However, you may
also specify command line arguments (including wildcards). Alternately, you can specify "" to indicate
that the command may only be run without command line arguments. A directory is a fully qualified path-
name ending in a '/'. When you specify a directory in a Cmnd_List, the user will be able to run any file
within that directory (but not in any subdirectories therein).
If a Cmnd has associated command line arguments, then the arguments in the Cmnd must match exactly those
given by the user on the command line (or match the wildcards if there are any). Note that the following
characters must be escaped with a '' if they are used in command arguments: ',', ':', '=', ''. The
special command "sudoedit" is used to permit a user to run sudo with the -e flag (or as sudoedit). It
may take command line arguments just as a normal command does.
Defaults(默认的配置参数，具体有哪些参数其后有说明，了解即可)
Certain configuration options may be changed from their default values at runtime via one or more
Default_Entry lines. These may affect all users on any host, all users on a specific host, a specific
user, or commands being run as a specific user.
Default_Type ::= 'Defaults' |
'Defaults' '@' Host_List |
'Defaults' ':' User_List |
'Defaults' '>' Runas_List
Default_Entry ::= Default_Type Parameter_List
Parameter_List ::= Parameter |
Parameter ',' Parameter_List
Parameter ::= Parameter '=' Value |
Parameter '+=' Value |
Parameter '-=' Value |
'!'* Parameter
Parameters may be flags, integer values, strings, or lists. Flags are implicitly boolean and can be
turned off via the '!' operator. Some integer, string and list parameters may also be used in a boolean
context to disable them. Values may be enclosed in double quotes (") when they contain multiple words.
Special characters may be escaped with a backslash ().
Lists have two additional assignment operators, += and -=. These operators are used to add to and delete
from a list respectively. It is not an error to use the -= operator to remove an element that does not
exist in a list.
See "SUDOERS OPTIONS" for a list of supported Defaults parameters.
User Specification
User_Spec ::= User_List Host_List '=' Cmnd_Spec_List
(':' Host_List '=' Cmnd_Spec_List)*
Cmnd_Spec_List ::= Cmnd_Spec |
Cmnd_Spec ',' Cmnd_Spec_List
Cmnd_Spec ::= Runas_Spec? Tag_Spec* Cmnd
Runas_Spec ::= '(' Runas_List ')'
Tag_Spec ::= ('NOPASSWD:' | 'PASSWD:' | 'NOEXEC:' | 'EXEC:' |
'SETENV:' | 'NOSETENV:')
A user specification determines which commands a user may run (and as what user) on specified hosts. By
default, commands are run as root, but this can be changed on a per-command basis.
Let's break that down into its constituent parts:
Runas_Spec
A Runas_Spec is simply a Runas_List (as defined above) enclosed(附带的) in a set of parentheses. If you do not
specify a Runas_Spec in the user specification, a default Runas_Spec of root will be used. A Runas_Spec
sets the default for commands that follow it. What this means is that for the entry:
dgb boulder = (operator) /bin/ls, /bin/kill, /usr/bin/lprm
The user dgb may run /bin/ls, /bin/kill, and /usr/bin/lprm -- but only as operator. E.g.,
$ sudo -u operator /bin/ls.
It is also possible to override a Runas_Spec later on in an entry. If we modify the entry like so:
dgb boulder = (operator) /bin/ls, (root) /bin/kill, /usr/bin/lprm
Then user dgb is now allowed to run /bin/ls as operator, but /bin/kill and /usr/bin/lprm as root.
Tag_Spec
A command may have zero or more tags associated with it. There are six possible tag values, NOPASSWD,
PASSWD, NOEXEC, EXEC, SETENV and NOSETENV. Once a tag is set on a Cmnd, subsequent Cmnds in the
Cmnd_Spec_List, inherit the tag unless it is overridden by the opposite tag (i.e.: PASSWD overrides
NOPASSWD and NOEXEC overrides EXEC).
NOPASSWD and PASSWD
By default, sudo requires that a user authenticate him or herself before running a command. This behav-
ior can be modified via the NOPASSWD tag. Like a Runas_Spec, the NOPASSWD tag sets a default for the
commands that follow it in the Cmnd_Spec_List. Conversely, the PASSWD tag can be used to reverse things.
For example:
ray rushmore = NOPASSWD: /bin/kill, /bin/ls, /usr/bin/lprm
would allow the user ray to run /bin/kill, /bin/ls, and /usr/bin/lprm as root on the machine rushmore as
root without authenticating himself. If we only want ray to be able to run /bin/kill without a password
the entry would be:
ray rushmore = NOPASSWD: /bin/kill, PASSWD: /bin/ls, /usr/bin/lprm
Note, however, that the PASSWD tag has no effect on users who are in the group specified by the
exempt_group option.
By default, if the NOPASSWD tag is applied to any of the entries for a user on the current host, he or
she will be able to run sudo -l without a password. Additionally, a user may only run sudo -v without a
password if the NOPASSWD tag is present for all a user's entries that pertain to the current host. This
behavior may be overridden via the verifypw and listpw options.
NOEXEC and EXEC
If sudo has been compiled with noexec support and the underlying operating system supports it, the NOEXEC
tag can be used to prevent a dynamically-linked executable from running further commands itself.
In the following example, user aaron may run /usr/bin/more and /usr/bin/vi but shell escapes will be dis-
abled.
aaron shanty = NOEXEC: /usr/bin/more, /usr/bin/vi
See the "PREVENTING SHELL ESCAPES" section below for more details on how NOEXEC works and whether or not
it will work on your system.
SETENV and NOSETENV
These tags override the value of the setenv option on a per-command basis. Note that if SETENV has been
set for a command, any environment variables set on the command line way are not subject to the restric-
tions imposed by env_check, env_delete, or env_keep. As such, only trusted users should be allowed to
set variables in this manner. If the command matched is ALL, the SETENV tag is implied for that command;
this default may be overridden by use of the UNSETENV tag.
Wildcards（通配符）
sudo allows shell-style wildcards (aka meta or glob characters) to be used in pathnames as well as com-
mand line arguments in the sudoers file. Wildcard matching is done via the POSIX fnmatch(3) routine.
Note that these are not regular expressions.
* Matches any set of zero or more characters.
? Matches any single character.
[...] Matches any character in the specified range.
[!...] Matches any character not in the specified range.
x For any character "x", evaluates to "x". This is used to escape special characters such as: "*",
"?", "[", and "}".
Note that a forward slash ('/') will not be matched by wildcards used in the pathname. When matching the
command line arguments, however, a slash does get matched by wildcards. This is to make a path like:
/usr/bin/*
match /usr/bin/who but not /usr/bin/X11/xterm.
Exceptions to wildcard rules
The following exceptions apply to the above rules:
"" If the empty string "" is the only command line argument in the sudoers entry it means that com-
mand is not allowed to be run with any arguments.
Other special characters and reserved words
The pound sign ('#') is used to indicate a comment (unless it is part of a #include directive or unless
it occurs in the context of a user name and is followed by one or more digits, in which case it is
treated as a uid). Both the comment character and any text after it, up to the end of the line, are
ignored.
The reserved word ALL is a built-in alias that always causes a match to succeed. It can be used wherever
one might otherwise use a Cmnd_Alias, User_Alias, Runas_Alias, or Host_Alias. You should not try to
define your own alias called ALL as the built-in alias will be used in preference to your own. Please
note that using ALL can be dangerous since in a command context, it allows the user to run any command on
the system.
An exclamation point ('!') can be used as a logical not operator both in an alias and in front of a Cmnd.
This allows one to exclude certain values. Note, however, that using a ! in conjunction with the built-
in ALL alias to allow a user to run "all but a few" commands rarely works as intended (see SECURITY NOTES
below).
Long lines can be continued with a backslash ('') as the last character on the line.
Whitespace between elements in a list as well as special syntactic characters in a User Specification
('=', ':', '(', ')') is optional.
The following characters must be escaped with a backslash ('') when used as part of a word (e.g. a user-
name or hostname): '@', '!', '=', ':', ',', '(', ')', ''.
SUDOERS OPTIONS
sudo's behavior can be modified by Default_Entry lines, as explained earlier. A list of all supported
Defaults parameters, grouped by type, are listed below.
Flags:
……
Integers:
passwd_tries The number of tries a user gets to enter his/her password before sudo logs the failure
and exits. The default is 3.
Integers that can be used in a boolean context:
……
Strings:
……
Strings that can be used in a boolean context:
……
Lists that can be used in a boolean context:
……
FILES
/etc/sudoers List of who can run what
/etc/group Local groups file
/etc/netgroup List of network groups
EXAMPLES
Since the sudoers file is parsed in a single pass, order is important. In general, you should structure
sudoers such that the Host_Alias, User_Alias, and Cmnd_Alias specifications come first, followed by any
Default_Entry lines, and finally the Runas_Alias and user specifications. The basic rule of thumb is you
cannot reference an Alias that has not already been defined.
Below are example sudoers entries. Admittedly, some of these are a bit contrived (人造的, 勉强的, 不自然的). First, we define our
aliases:
# User alias specification
User_Alias FULLTIMERS = millert, mikef, dowdy
User_Alias PARTTIMERS = bostley, jwfox, crawl
User_Alias WEBMASTERS = will, wendy, wim
# Runas alias specification
Runas_Alias OP = root, operator
Runas_Alias DB = oracle, sybase
# Host alias specification
Host_Alias SPARC = bigtime, eclipse, moet, anchor :
SGI = grolsch, dandelion, black :
ALPHA = widget, thalamus, foobar :
HPPA = boa, nag, python
Host_Alias CUNETS = 128.138.0.0/255.255.0.0
Host_Alias CSNETS = 128.138.243.0, 128.138.204.0/24, 128.138.242.0
Host_Alias SERVERS = master, mail, www, ns
Host_Alias CDROM = orion, perseus, hercules
# Cmnd alias specification
Cmnd_Alias DUMPS = /usr/bin/mt, /usr/sbin/dump, /usr/sbin/rdump,
/usr/sbin/restore, /usr/sbin/rrestore
Cmnd_Alias KILL = /usr/bin/kill
Cmnd_Alias PRINTING = /usr/sbin/lpc, /usr/bin/lprm
Cmnd_Alias SHUTDOWN = /usr/sbin/shutdown
Cmnd_Alias HALT = /usr/sbin/halt
Cmnd_Alias REBOOT = /usr/sbin/reboot
Cmnd_Alias SHELLS = /usr/bin/sh, /usr/bin/csh, /usr/bin/ksh,
/usr/local/bin/tcsh, /usr/bin/rsh,
/usr/local/bin/zsh
Cmnd_Alias SU = /usr/bin/su
Cmnd_Alias PAGERS = /usr/bin/more, /usr/bin/pg, /usr/bin/less
Here we override (废除) some of the compiled in default values. We want sudo to log via syslog(3) using the
auth facility in all cases. We don't want to subject the full time staff to the sudo lecture, user
millert need not give a password, and we don't want to reset the LOGNAME, USER or USERNAME environment
variables when running commands as root. Additionally, on the machines in the SERVERS Host_Alias, we
keep an additional local log file and make sure we log the year in each log line since the log entries
will be kept around for several years. Lastly, we disable shell escapes for the commands in the PAGERS
Cmnd_Alias (/usr/bin/more, /usr/bin/pg and /usr/bin/less).
# Override built-in defaults
Defaults syslog=auth
Defaults>root !set_logname
Defaults:FULLTIMERS !lecture
Defaults:millert !authenticate
Defaults@SERVERS log_year, logfile=/var/log/sudo.log
Defaults!PAGERS noexec
The User specification is the part that actually determines who may run what.
root ALL = (ALL) ALL
%wheel ALL = (ALL) ALL
We let root and any user in group wheel run any command on any host as any user.
FULLTIMERS ALL = NOPASSWD: ALL
Full time sysadmins (millert, mikef, and dowdy) may run any command on any host without authenticating
themselves.
PARTTIMERS ALL = ALL
Part time sysadmins (bostley, jwfox, and crawl) may run any command on any host but they must authenti-
cate themselves first (since the entry lacks the NOPASSWD tag).
jack CSNETS = ALL
The user jack may run any command on the machines in the CSNETS alias (the networks 128.138.243.0,
128.138.204.0, and 128.138.242.0). Of those networks, only 128.138.204.0 has an explicit netmask (in
CIDR notation) indicating it is a class C network. For the other networks in CSNETS, the local machine's
netmask will be used during matching.
lisa CUNETS = ALL
The user lisa may run any command on any host in the CUNETS alias (the class B network 128.138.0.0).
operator ALL = DUMPS, KILL, SHUTDOWN, HALT, REBOOT, PRINTING,
sudoedit /etc/printcap, /usr/oper/bin/
The operator user may run commands limited to simple maintenance. Here, those are commands related to
backups, killing processes, the printing system, shutting down the system, and any commands in the direc-
tory /usr/oper/bin/.
joe ALL = /usr/bin/su operator
The user joe may only su(1) to operator.
pete HPPA = /usr/bin/passwd [A-z]*, !/usr/bin/passwd root
The user pete is allowed to change anyone's password except for root on the HPPA machines. Note that
this assumes passwd(1) does not take multiple usernames on the command line.
bob SPARC = (OP) ALL : SGI = (OP) ALL
The user bob may run anything on the SPARC and SGI machines as any user listed in the OP Runas_Alias
(root and operator).
jim +biglab = ALL
The user jim may run any command on machines in the biglab netgroup. sudo knows that "biglab" is a net-
group due to the '+' prefix.
+secretaries ALL = PRINTING, /usr/bin/adduser, /usr/bin/rmuser
Users in the secretaries netgroup need to help manage the printers as well as add and remove users, so
they are allowed to run those commands on all machines.
fred ALL = (DB) NOPASSWD: ALL
The user fred can run commands as any user in the DB Runas_Alias (oracle or sybase) without giving a
password.
john ALPHA = /usr/bin/su [!-]*, !/usr/bin/su *root*
On the ALPHA machines, user john may su to anyone except root but he is not allowed to give su(1) any
flags.
jen ALL, !SERVERS = ALL
The user jen may run any command on any machine except for those in the SERVERS Host_Alias (master, mail,
www and ns).
jill SERVERS = /usr/bin/, !SU, !SHELLS
For any machine in the SERVERS Host_Alias, jill may run any commands in the directory /usr/bin/ except
for those commands belonging to the SU and SHELLS Cmnd_Aliases.
steve CSNETS = (operator) /usr/local/op_commands/
The user steve may run any command in the directory /usr/local/op_commands/ but only as user operator.
matt valkyrie = KILL
On his personal workstation, valkyrie, matt needs to be able to kill hung processes.
WEBMASTERS www = (www) ALL, (root) /usr/bin/su www
On the host www, any user in the WEBMASTERS User_Alias (will, wendy, and wim), may run any command as
user www (which owns the web pages) or simply su(1) to www.
ALL CDROM = NOPASSWD: /sbin/umount /CDROM,
/sbin/mount -o nosuid,nodev /dev/cd0a /CDROM
Any user may mount or unmount a CD-ROM on the machines in the CDROM Host_Alias (orion, perseus, hercules)
without entering a password. This is a bit tedious for users to type, so it is a prime candidate for
encapsulating in a shell script.
root@fhc2007-desktop:~# cat /etc/sudoers # /etc/sudoers # # This file MUST be edited with the 'visudo' command as root. # # See the man page for details on how to write a sudoers file. # Defaults env_reset # Uncomment to allow members of group sudo to not need a password # %sudo ALL=NOPASSWD: ALL # Host alias specification # User alias specification # Cmnd alias specification # User privilege specification root ALL=(ALL) ALL # Members of the admin group may gain root privileges %admin ALL=(ALL) ALL root@fhc2007-desktop:~#