/etc/adduser.conf - configuration file for adduser(8) and addgroup(8).
The file /etc/adduser.conf contains defaults for the programs
adduser(8) , addgroup(8) , deluser(8) and delgroup(8). Each line holds
a single value pair in the form option = value. Double or single
quotes are allowed around the value, as is whitespace around the equals
sign. Comment lines must have a hash sign (#) in the first column.
The valid configuration options are:
DSHELL The login shell to be used for all new users. Defaults to
DHOME The directory in which new home directories should be created.
Defaults to /home.
If this is set to yes, the home directories will be created as
/home/[groupname]/user. Defaults to no.
If this is set to yes, then the home directories created will
have an extra directory inserted which is the first letter of
the loginname. For example: /home/u/user. Defaults to no.
SKEL The directory from which skeletal user configuration files
should be copied. Defaults to /etc/skel.
FIRST_SYSTEM_UID and LAST_SYSTEM_UID
specify an inclusive range of UIDs from which system UIDs can be
dynamically allocated. Default to 100 - 999. Please note that
system software, such as the users allocated by the base-passwd
package, may assume that UIDs less than 100 are unallocated.
FIRST_UID and LAST_UID
specify an inclusive range of UIDs from which normal user's UIDs
can be dynamically allocated. Default to 1000 - 29999.
FIRST_SYSTEM_GID and LAST_SYSTEM_GID
specify an inclusive range of GIDs from which system GIDs can be
dynamically allocated. Default to 100 - 999.
FIRST_GID and LAST_GID
specify an inclusive range of GIDs from which normal group's
GIDs can be dynamically allocated. Default to 1000 - 29999.
If this is set to yes, then each created user will be given
their own group to use. If this is no, then each created user
will be placed in the group whose GID is USERS_GID (see below).
The default is yes.
If USERGROUPS is no, then USERS_GID is the GID given to all
newly-created users. The default value is 100.
If set to a valid value (e.g. 0755 or 755), directories created
will have the specified permissions as umask. Otherwise 0755 is
used as default.
If this is set to yes, then home directories for users with
their own group ( USERGROUPS=yes ) will have the setgid bit set.
This was the default setting for adduser versions << 3.13.
Unfortunately it has some bad side effects, so we no longer do
this per default. If you want it nevertheless you can still
activate it here.
If set to a nonempty value, new users will have quotas copied
from that user. The default is empty.
User and group names are checked against this regular expres‐
sion. If the name doesn't match this regexp, user and group cre‐
ation in adduser is refused unless --force-badname is set. With
--force-badname set, only weak checks are performed. The default
is the most conservative ^[a-z][-a-z0-9]*$. When --system is
specified, NAME_REGEX_SYSTEM is used instead.
Names of system users are checked against this regular expres‐
sion. If --system is supplied and the name doesn't match this
regexp, user creation in adduser is refused unless --force-bad‐
name is set. With --force-badname set, only weak checks are per‐
formed. The default is as for the default NAME_REGEX but also
allowing uppercase letters.
Files in /etc/skel/ are checked against this regex, and not
copied to the newly created home directory if they match. This
is by default set to the regular expression matching files left
over from unmerged config files (dpkg-(old|new|dist)).
Setting this to something other than 0 (the default) will cause
adduser to add newly created non-system users to the list of
groups defined by EXTRA_GROUPS (below).
This is the list of groups that new non-system users will be
added to. By default, this list is 'dialout cdrom floppy audio
video plugdev users games'
adduser and addgroup enforce conformity to IEEE Std 1003.1-2001,
which allows only the following characters to appear in group
and user names: letters, digits, underscores, periods, at signs
(@) and dashes. The name may no start with a dash. The "$" sign
is allowed at the end of usernames (to conform to samba).
An additional check can be adjusted via the configuration param‐
eter NAME_REGEX to enforce a local policy.
SEE ALSOadduser(8), addgroup(8), deluser(8), delgroup(8), deluser.conf(5)Debian GNU/Linux Version 3.113+nmu3ubuntu3 adduser.conf(5)