'\" t
.\"     Title: login.defs
.\"    Author: Julianne Frances Haugh
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 30.07.2026
.\"    Manual: File Formats and Configuration Files
.\"    Source: shadow-utils 4.20.0
.\"  Language: German
.\"
.TH "LOGIN\&.DEFS" "5" "30.07.2026" "shadow\-utils 4\&.20\&.0" "File Formats and Configuration"
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.nh
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.\" * MAIN CONTENT STARTS HERE *
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.SH "NAME"
login.defs \- Konfiguration der Shadow\-Passwort\-Programmsammlung
.SH "BESCHREIBUNG"
.PP
The
/etc/login\&.defs
file defines the site\-specific configuration for the shadow password suite\&. This file is required\&. Absence of this file will not prevent system operation, but will probably result in undesirable operation\&.
.PP
Diese Datei ist eine lesbare Textdatei\&. Jede Zeile der Datei beschreibt einen Konfigurationsparameter und besteht aus dessen Namen und einem Wert; beides durch Leerraumzeichen voneinander getrennt\&. Leer\- und Kommentarzeilen werden nicht beachtet\&. Kommentare werden mit dem Rautezeichen \(Fc#\(Fo eingeleitet, wobei es das erste nicht leere Zeichen der Zeile sein muss\&.
.PP
Parameter values may be of four types: strings, booleans, numbers, and long numbers\&. A string is comprised of any printable characters\&. A boolean should be either the value
\fIyes\fR
or
\fIno\fR\&. An undefined boolean parameter or one with a value other than these will be given a
\fIno\fR
value\&. Numbers (both regular and long) may be either decimal values, octal values (precede the value with
\fI0\fR) or hexadecimal values (precede the value with
\fI0x\fR)\&. The maximum value of the regular and long numeric parameters is machine\-dependent\&.
.PP
This configuration file controls the behavior of system tools for user and group management\&. The parameters may be used by shadow\-utils programs, PAM modules, and other system components\&. The actual behavior depends on the system configuration and which authentication mechanisms are enabled\&.
.PP
Folgende Merkmale k\(:onnen konfiguriert werden:
.PP
\fBCHFN_RESTRICT\fR (string)
.RS 4
This parameter specifies which values in the
\fIgecos\fR
field of the
/etc/passwd
file may be changed by regular users using the
\fBchfn\fR
program\&. It can be any combination of letters
\fIf\fR,
\fIr\fR,
\fIw\fR,
\fIh\fR, for Full name, Room number, Work phone, and Home phone, respectively\&. For backward compatibility,
\fIyes\fR
is equivalent to
\fIrwh\fR
and
\fIno\fR
is equivalent to
\fIfrwh\fR\&. If not specified, only the superuser can make any changes\&. The most restrictive setting is better achieved by not installing
\fBchfn\fR
SUID\&.
.RE
.PP
\fBCREATE_HOME\fR (boolean)
.RS 4
bestimmt, ob standardm\(:a\(ssig f\(:ur neue Benutzer ein pers\(:onliches Verzeichnis erstellt werden soll\&.
.sp
Diese Einstellung gilt nicht f\(:ur Systemkonten und kann per Befehlszeile au\(sser Kraft gesetzt werden\&.
.RE
.PP
\fBDEFAULT_HOME\fR (boolean)
.RS 4
Legt fest, ob eine Anmeldung erlaubt ist, wenn nicht in das pers\(:onliche Verzeichnis gewechselt werden kann\&. Voreingestellt ist
\fIno\fR\&.
.sp
If set to
\fIyes\fR, the user will login in the root (/) directory if it is not possible to cd to her home directory\&.
.RE
.PP
\fBENCRYPT_METHOD\fR (string)
.RS 4
This defines the system default encryption algorithm for encrypting passwords (if no algorithm is specified on the command line)\&.
.sp
It can take one of these values:
\fISHA256\fR,
\fISHA512\fR
(default),
\fIYESCRYPT\fR\&. See
crypt(5)
for recommendations\&.
.sp
Note: this only affects the generation of group passwords\&. The generation of user passwords is done by PAM and subject to the PAM configuration\&. It is recommended to set this variable consistently with the PAM configuration\&.
.sp
History: This variable is used by other programs, which may still default to unsafe algorithms such as DES\&. To avoid using unsafe algorithms, the variable should always be specified\&.
.RE
.PP
\fBENV_PATH\fR (string)
.RS 4
If set, it will be used to define the PATH environment variable when a regular user login\&. The value is a colon separated list of paths (for example
\fI/bin:/usr/bin\fR) and can be preceded by
\fIPATH=\fR\&. The default value is
\fIPATH=/bin:/usr/bin\fR\&.
.RE
.PP
\fBENV_SUPATH\fR (string)
.RS 4
If set, it will be used to define the PATH environment variable when the superuser login\&. The value is a colon separated list of paths (for example
\fI/sbin:/bin:/usr/sbin:/usr/bin\fR) and can be preceded by
\fIPATH=\fR\&. The default value is
\fIPATH=/sbin:/bin:/usr/sbin:/usr/bin\fR\&.
.RE
.PP
\fBFAIL_DELAY\fR (number)
.RS 4
Wartezeit nach einem Anmeldefehlschlag in Sekunden, ehe ein neuer Versuch unternommen werden kann\&.
.RE
.PP
\fBGID_MAX\fR (number), \fBGID_MIN\fR (number)
.RS 4
Range of group IDs used for the creation of regular groups by
\fBuseradd\fR,
\fBgroupadd\fR, or
\fBnewusers\fR\&.
.sp
The default value for
\fBGID_MIN\fR
(resp\&.
\fBGID_MAX\fR) is 1000 (resp\&. 60000)\&.
.RE
.PP
\fBHOME_MODE\fR (number)
.RS 4
The mode for new home directories\&. If not specified, the
\fBUMASK\fR
is used to create the mode\&.
.sp
\fBuseradd\fR
and
\fBnewusers\fR
use this to set the mode of the home directory they create\&.
.RE
.PP
\fBHUSHLOGIN_FILE\fR (string)
.RS 4
Falls angegeben, kann diese Datei die nach Anmeldung \(:ubliche Anzeige von Informationen unterbinden\&. Der Modus ohne Anmeldeinformationen (\(Fchushed login mode\(Fo) ist eingestellt, wenn ein vollst\(:andiger Pfad angegeben ist und in dieser Datei der Name oder die Shell des Benutzers genannt ist\&. Wenn kein vollst\(:andiger Pfad angegeben ist, aber diese Datei im pers\(:onlichen Verzeichnis des Benutzers existiert, wird ebenfalls dieser Modus aktiviert\&.
.RE
.PP
\fBLASTLOG_UID_MAX\fR (number)
.RS 4
Die h\(:ochste Benutzerkennung, die
\fBlastlog\fR
bei den Aufzeichnungen ber\(:ucksichtigen soll\&. Da gew\(:ohnlich spezielle Dienste die Identit\(:at und Authentizit\(:at von Benutzern an entfernten Systemen protokollieren, gibt es keinen Grund, ihretwegen eine riesige Sparse\-Datei
lastlog
anzulegen\&.
.sp
No
\fBLASTLOG_UID_MAX\fR
option present in the configuration means that there is no user ID limit for writing lastlog entries\&.
.RE
.PP
\fBLOG_UNKFAIL_ENAB\fR (boolean)
.RS 4
Aktiviert die Anzeige unbekannter Benutzernamen, wenn fehlgeschlagene Anmeldeversuche aufgezeichnet werden\&.
.sp
Hinweis: Das Protokollieren unbekannter Benutzernamen kann ein Sicherheitsproblem darstellen, wenn ein Benutzer sein Passwort anstelle seines Anmeldenamens eingibt\&.
.RE
.PP
\fBLOGIN_RETRIES\fR (number)
.RS 4
Die maximale Anzahl von Versuchen, wenn zur Anmeldung falsche Passw\(:orter eingegeben werden\&.
.sp
Dieser Parameter ist sehr wahrscheinlich auf Systemen mit PAM au\(sser Kraft gesetzt, da das Modul \(Fcpam_unix\(Fo standardm\(:a\(ssig drei Versuche vorsieht\&. Er gew\(:ahrt jedoch gewisse Sicherheit, falls Sie ein Authentifizierungsmodul verwenden, das PAM_MAXTRIES nicht anwendet\&.
.RE
.PP
\fBLOGIN_TIMEOUT\fR (number)
.RS 4
H\(:ochstdauer f\(:ur einen Anmeldeversuch in Sekunden
.RE
.PP
\fBMAIL_DIR\fR (string)
.RS 4
The mail spool directory\&. This is needed to manipulate the mailbox when its corresponding user account is modified or deleted\&. If not specified, a compile\-time default is used\&. The parameter CREATE_MAIL_SPOOL in
/etc/default/useradd
determines whether the mail spool should be created\&.
.RE
.PP
\fBMAIL_FILE\fR (string)
.RS 4
legt fest, wo sich die Dateien der Mail\-Warteschlange des Benutzers relativ zu seinem pers\(:onlichen Verzeichnis befinden\&.
.RE
.PP
The
\fBMAIL_DIR\fR
and
\fBMAIL_FILE\fR
variables are used by
\fBuseradd\fR,
\fBusermod\fR, and
\fBuserdel\fR
to create, move, or delete the user\*(Aqs mail spool\&.
.PP
\fBMAX_MEMBERS_PER_GROUP\fR (number)
.RS 4
Maximum members per group entry\&. When the maximum is reached, a new group entry (line) is started in
/etc/group
(with the same name, same password, and same GID)\&.
.sp
Der Standardwert ist 0, was bedeutet, dass die Anzahl der Mitglieder einer Gruppe nicht begrenzt ist\&.
.sp
Das Aufteilen von Gruppen erm\(:oglicht es, L\(:angenvorgaben f\(:ur die Zeilen der Gruppendatei einzuhalten\&. Damit kann sichergestellt werden, dass die Zeilen f\(:ur NIS\-Gruppen nicht l\(:anger als 1024 Zeichen sind\&.
.sp
Falls Sie eine solche Begrenzung ben\(:otigen, k\(:onnen Sie 25 verwenden\&.
.sp
Hinweis: Mit aufgeteilten Gruppen k\(:onnen m\(:oglicherweise nicht alle Hilfsprogramme (nicht einmal jene der Shadow\-Programmsammlung) umgehen\&. Sie sollten diese Variable nur setzen, wenn Sie sie wirklich ben\(:otigen\&.
.RE
.PP
\fBNONEXISTENT\fR (string)
.RS 4
If a system account intentionally does not have a home directory that exists, this string can be provided in the /etc/passwd entry for the account to indicate this\&. The result is that pwck will not emit a spurious warning for this account\&.
.RE
.PP
\fBPASS_MAX_DAYS\fR (number)
.RS 4
die maximale Anzahl von Tagen, die ein Passwort verwendet werden darf\&. Wenn das Passwort \(:alter ist, wird ein Wechsel des Passworts erzwungen\&. Falls nicht definiert, wird \-1 angenommen, womit Passw\(:orter unbefristet gelten\&.
.RE
.PP
\fBPASS_WARN_AGE\fR (number)
.RS 4
The number of days warning given before a password expires\&. A zero means warning is given only upon the day of expiration, a value of \-1 means no warning is given\&. If not specified, no warning will be provided\&.
.RE
.PP
\fBPASS_MAX_DAYS\fR, and
\fBPASS_WARN_AGE\fR
are only used at the time of account creation\&. Any changes to these settings won\*(Aqt affect existing accounts\&.
.PP
\fBSHA_CRYPT_MIN_ROUNDS\fR (number), \fBSHA_CRYPT_MAX_ROUNDS\fR (number)
.RS 4
When
\fBENCRYPT_METHOD\fR
is set to
\fISHA256\fR
or
\fISHA512\fR, this defines the number of SHA rounds used by the encryption algorithm by default (when the number of rounds is not specified on the command line)\&.
.sp
With a lot of rounds, it is more difficult to brute force the password\&. But note also that more CPU resources will be needed to authenticate users\&.
.sp
If not specified, the libc will choose the default number of rounds (5000), which is orders of magnitude too low for modern hardware\&.
.sp
Die Werte m\(:ussen zwischen 1000 und 999\&.999\&.999 liegen\&.
.sp
If only one of the
\fBSHA_CRYPT_MIN_ROUNDS\fR
or
\fBSHA_CRYPT_MAX_ROUNDS\fR
values is set, then this value will be used\&.
.sp
If
\fBSHA_CRYPT_MIN_ROUNDS\fR
>
\fBSHA_CRYPT_MAX_ROUNDS\fR, the highest value will be used\&.
.sp
Note: this only affect the generation of group passwords\&. The generation of user passwords is done by PAM and subject to the PAM configuration\&. It is recommended to set this variable consistently with the PAM configuration\&.
.RE
.PP
\fBSUB_GID_MIN\fR (number), \fBSUB_GID_MAX\fR (number), \fBSUB_GID_COUNT\fR (number)
.RS 4
If
/etc/subuid
exists, the commands
\fBuseradd\fR
and
\fBnewusers\fR
(unless the user already have subordinate group IDs) allocate
\fBSUB_GID_COUNT\fR
unused group IDs from the range
\fBSUB_GID_MIN\fR
to
\fBSUB_GID_MAX\fR
for each new user\&.
.sp
The default values for
\fBSUB_GID_MIN\fR,
\fBSUB_GID_MAX\fR,
\fBSUB_GID_COUNT\fR
are respectively 100000, 600100000 and 65536\&.
.RE
.PP
\fBSUB_GID_DETERMINISTIC\fR (boolean)
.RS 4
If set to
\fIyes\fR, the commands
\fBuseradd\fR,
\fBusermod\fR, and
\fBnewusers\fR
will calculate subordinate GID ranges deterministically based on the user\*(Aqs UID instead of searching for the next free range\&. The formula used is:
.sp
.if n \{\
.RS 4
.\}
.nf
      start = SUB_GID_MIN + ((UID \- UID_MIN) * SUB_GID_COUNT)
      end   = start + SUB_GID_COUNT \- 1
    
.fi
.if n \{\
.RE
.\}
.sp
This ensures the same UID always receives the same subordinate GID range on every system, making it suitable for environments with centralized user management (LDAP, NIS, etc\&.) or synchronized UIDs across systems\&.
.sp
If
\fBSUB_GID_DETERMINISTIC\fR
is enabled, you can use
\fBusermod \-\-add\-subgids \-S\fR
to produce deterministic subgids\&.
.sp
\fBWARNING\fR: Because
\fBUID_MIN\fR
is used to calculate the ranges, any change of
\fBUID_MIN\fR
will change the ranges calculated\&.
\fBSUB_GID_COUNT\fR
is used to calculate the ranges, any change of
\fBSUB_GID_COUNT\fR
will change the ranges calculated\&. Users with identities less than
\fBUID_MIN\fR
are incompatible with
\fBSUB_GID_DETERMINISTIC\fR, but can still be set manually\&.
.sp
\fBWARNING\fR: Do not mix deterministic and linear (default) allocation on the same system or across systems sharing
/etc/subgid
via network storage (NFS, etc\&.)\&. Mixing allocation methods
\fB will cause subordinate ID range conflicts and overlaps \fR\&.
.sp
The default value for
\fBSUB_GID_DETERMINISTIC\fR
is
\fIno\fR\&.
.SS "Range Calculation Examples"
With default configuration (\fBUID_MIN\fR=1000,
\fBSUB_GID_MIN\fR=100000,
\fBSUB_GID_COUNT\fR=65536):
.TS
allbox tab(:);
lB lB lB.
T{
UID
T}:T{
Calculation
T}:T{
Subordinate GID Range
T}
.T&
l l l
l l l
l l l
l l l.
T{
1000
T}:T{
100000 + ((1000\-1000) * 65536)
T}:T{
100000\-165535
T}
T{
1001
T}:T{
100000 + ((1001\-1000) * 65536)
T}:T{
165536\-231071
T}
T{
1002
T}:T{
100000 + ((1002\-1000) * 65536)
T}:T{
231072\-296607
T}
T{
1100
T}:T{
100000 + ((1100\-1000) * 65536)
T}:T{
6653600\-6719135
T}
.TE
.sp 1
.SS "Subordinate ID Space Planning"
When planning subordinate ID allocation, calculate the maximum number of users the space can accommodate:
.sp
.if n \{\
.RS 4
.\}
.nf
      capacity = (SUB_GID_MAX \- SUB_GID_MIN) / SUB_GID_COUNT
      
.fi
.if n \{\
.RE
.\}
.sp
With default values: (600100000 \- 100000) / 65536 ≈ 9155 users\&.
.sp
For high\-density environments with many users and smaller allocations:
.sp
.if n \{\
.RS 4
.\}
.nf
        SUB_GID_COUNT  4096
        SUB_GID_MIN    100000
        SUB_GID_MAX    10000000
      
.fi
.if n \{\
.RE
.\}
.sp
This gives: (10000000 \- 100000) / 4096 ≈ 2417 users\&.
.RE
.PP
\fBUNSAFE_SUB_GID_DETERMINISTIC_WRAP\fR (boolean)
.RS 4
\fB WARNING: SECURITY RISK \- MAY CAUSE RANGE OVERLAPS AND PRIVILEGE ESCALATION! \fR
.sp
Only effective when
\fBSUB_GID_DETERMINISTIC\fR
is set to
\fIyes\fR\&.
.sp
When set to
\fIyes\fR
(WRAP MODE), allows the deterministic range calculation to wrap around using modulo arithmetic when a UID would overflow the configured subordinate ID space\&. The subordinate ID space is treated as a ring buffer\&.
.sp
\fBWARNING\fR: Range overlaps can lead to container escapes and privilege escalation\&. For example, with
\fBSUB_GID_MIN\fR=100000,
\fBSUB_GID_MAX\fR=200000,
\fBSUB_GID_COUNT\fR=65536, User A (UID 1000) gets range [100000, 165535] and User B (UID 1001) wraps and overlaps with User A\&. User B\*(Aqs container can now access files from User A\*(Aqs containers\&.
.sp
Use
\fBonly\fR
in development, testing, or tightly constrained lab environments\&.
.sp
When set to
\fIno\fR
(default), any arithmetic overflow or range exceeding
\fBSUB_GID_MAX\fR
is a hard error\&. This guarantees non\-overlapping, monotonic allocation\&.
.sp
The default value for
\fBUNSAFE_SUB_GID_DETERMINISTIC_WRAP\fR
is
\fIno\fR\&.
.RE
.PP
\fBSUB_GID_STORE_BY_UID\fR (boolean)
.RS 4
If set to
\fIyes\fR, subordinate group ID entries in
/etc/subgid
are stored using the numeric user ID rather than the username\&. The default value is
\fIno\fR\&.
.RE
.PP
\fBSUB_UID_MIN\fR (number), \fBSUB_UID_MAX\fR (number), \fBSUB_UID_COUNT\fR (number)
.RS 4
If
/etc/subuid
exists, the commands
\fBuseradd\fR
and
\fBnewusers\fR
(unless the user already have subordinate user IDs) allocate
\fBSUB_UID_COUNT\fR
unused user IDs from the range
\fBSUB_UID_MIN\fR
to
\fBSUB_UID_MAX\fR
for each new user\&.
.sp
The default values for
\fBSUB_UID_MIN\fR,
\fBSUB_UID_MAX\fR,
\fBSUB_UID_COUNT\fR
are respectively 100000, 600100000 and 65536\&.
.RE
.PP
\fBSUB_UID_DETERMINISTIC\fR (boolean)
.RS 4
If set to
\fIyes\fR, the commands
\fBuseradd\fR,
\fBusermod\fR, and
\fBnewusers\fR
will calculate subordinate UID ranges deterministically based on the user\*(Aqs UID instead of searching for the next free range\&. The formula used is:
.sp
.if n \{\
.RS 4
.\}
.nf
      start = SUB_UID_MIN + ((UID \- UID_MIN) * SUB_UID_COUNT)
      end   = start + SUB_UID_COUNT \- 1
    
.fi
.if n \{\
.RE
.\}
.sp
This ensures the same UID always receives the same subordinate UID range on every system, making it suitable for environments with centralized user management (LDAP, NIS, etc\&.) or synchronized UIDs across systems\&.
.sp
If
\fBSUB_UID_DETERMINISTIC\fR
is enabled, you can use
\fBusermod \-\-add\-subuids \-S\fR
to produce deterministic subuids\&.
.sp
\fBWARNING\fR: Because
\fBUID_MIN\fR
is used to calculate the ranges, any change of
\fBUID_MIN\fR
will change the ranges calculated\&.
\fBSUB_UID_COUNT\fR
is used to calculate the ranges, any change of
\fBSUB_UID_COUNT\fR
will change the ranges calculated\&. Users with identities less than
\fBUID_MIN\fR
are incompatible with
\fBSUB_UID_DETERMINISTIC\fR, but can still be set manually\&.
.sp
\fBWARNING\fR: Do not mix deterministic and linear (default) allocation on the same system or across systems sharing
/etc/subuid
via network storage (NFS, etc\&.)\&. Mixing allocation methods
\fB will cause subordinate ID range conflicts and overlaps \fR\&.
.sp
The default value for
\fBSUB_UID_DETERMINISTIC\fR
is
\fIno\fR\&.
.SS "Range Calculation Examples"
With default configuration (\fBUID_MIN\fR=1000,
\fBSUB_UID_MIN\fR=100000,
\fBSUB_UID_COUNT\fR=65536):
.TS
allbox tab(:);
lB lB lB.
T{
UID
T}:T{
Calculation
T}:T{
Subordinate UID Range
T}
.T&
l l l
l l l
l l l
l l l.
T{
1000
T}:T{
100000 + ((1000\-1000) * 65536)
T}:T{
100000\-165535
T}
T{
1001
T}:T{
100000 + ((1001\-1000) * 65536)
T}:T{
165536\-231071
T}
T{
1002
T}:T{
100000 + ((1002\-1000) * 65536)
T}:T{
231072\-296607
T}
T{
1100
T}:T{
100000 + ((1100\-1000) * 65536)
T}:T{
6653600\-6719135
T}
.TE
.sp 1
.SS "Subordinate ID Space Planning"
When planning subordinate ID allocation, calculate the maximum number of users the space can accommodate:
.sp
.if n \{\
.RS 4
.\}
.nf
      capacity = (SUB_UID_MAX \- SUB_UID_MIN) / SUB_UID_COUNT
      
.fi
.if n \{\
.RE
.\}
.sp
With default values: (600100000 \- 100000) / 65536 ≈ 9155 users\&.
.sp
For high\-density environments with many users and smaller allocations:
.sp
.if n \{\
.RS 4
.\}
.nf
        SUB_UID_COUNT  4096
        SUB_UID_MIN    100000
        SUB_UID_MAX    10000000
      
.fi
.if n \{\
.RE
.\}
.sp
This gives: (10000000 \- 100000) / 4096 ≈ 2417 users\&.
.RE
.PP
\fBUNSAFE_SUB_UID_DETERMINISTIC_WRAP\fR (boolean)
.RS 4
\fB WARNING: SECURITY RISK \- MAY CAUSE RANGE OVERLAPS AND PRIVILEGE ESCALATION! \fR
.sp
Only effective when
\fBSUB_UID_DETERMINISTIC\fR
is set to
\fIyes\fR\&.
.sp
When set to
\fIyes\fR
(WRAP MODE), allows the deterministic range calculation to wrap around using modulo arithmetic when a UID would overflow the configured subordinate ID space\&. The subordinate ID space is treated as a ring buffer\&.
.sp
\fBWARNING\fR: Range overlaps can lead to container escapes and privilege escalation\&. For example, with
\fBSUB_UID_MIN\fR=100000,
\fBSUB_UID_MAX\fR=200000,
\fBSUB_UID_COUNT\fR=65536, User A (UID 1000) gets range [100000, 165535] and User B (UID 1001) wraps and overlaps with User A\&. User B\*(Aqs container can now access files from User A\*(Aqs containers\&.
.sp
Use
\fBonly\fR
in development, testing, or tightly constrained lab environments\&.
.sp
When set to
\fIno\fR
(default), any arithmetic overflow or range exceeding
\fBSUB_UID_MAX\fR
is a hard error\&. This guarantees non\-overlapping, monotonic allocation\&.
.sp
The default value for
\fBUNSAFE_SUB_UID_DETERMINISTIC_WRAP\fR
is
\fIno\fR\&.
.RE
.PP
\fBSUB_UID_STORE_BY_UID\fR (boolean)
.RS 4
If set to
\fIyes\fR, subordinate user ID entries in
/etc/subuid
are stored using the numeric user ID rather than the username\&. The default value is
\fIno\fR\&.
.RE
.PP
\fBSYS_GID_MAX\fR (number), \fBSYS_GID_MIN\fR (number)
.RS 4
Range of group IDs used for the creation of system groups by
\fBuseradd\fR,
\fBgroupadd\fR, or
\fBnewusers\fR\&.
.sp
The default value for
\fBSYS_GID_MIN\fR
(resp\&.
\fBSYS_GID_MAX\fR) is 101 (resp\&.
\fBGID_MIN\fR\-1)\&.
.RE
.PP
\fBSYS_UID_MAX\fR (number), \fBSYS_UID_MIN\fR (number)
.RS 4
Range of user IDs used for the creation of system users by
\fBuseradd\fR
or
\fBnewusers\fR\&.
.sp
The default value for
\fBSYS_UID_MIN\fR
(resp\&.
\fBSYS_UID_MAX\fR) is 101 (resp\&.
\fBUID_MIN\fR\-1)\&.
.RE
.PP
\fBSYSLOG_SG_ENAB\fR (boolean)
.RS 4
Enable "syslog" logging of
\fBsg\fR
activity\&.
.RE
.PP
\fBTTYGROUP\fR (string), \fBTTYPERM\fR (number)
.RS 4
The terminal permissions: the login tty will be owned by the
\fBTTYGROUP\fR
group, and the permissions will be set to
\fBTTYPERM\fR\&.
.sp
\fBTTYGROUP\fR
can be either the name of a group or a numeric group identifier\&.
.sp
If TTYGROUP is not defined, then the group ownership of the terminal is set to the user\*(Aqs primary group\&. If TTYPERM is not defined, then the permissions are set to
\fI0600\fR\&.
.sp
If you have a
\fBwrite\fR
program which is "setgid" to a special group which owns the terminals, define TTYGROUP to the group number and TTYPERM to 0620\&. Otherwise leave TTYGROUP commented out and assign TTYPERM to either 622 or 600\&.
.RE
.PP
\fBUID_MAX\fR (number), \fBUID_MIN\fR (number)
.RS 4
Range of user IDs used for the creation of regular users by
\fBuseradd\fR
or
\fBnewusers\fR\&.
.sp
The default value for
\fBUID_MIN\fR
(resp\&.
\fBUID_MAX\fR) is 1000 (resp\&. 60000)\&.
.RE
.PP
\fBUMASK\fR (number)
.RS 4
Die Maske zum Berechtigungsmodus neu erstellter Dateien, siehe
\fBumask\fR(2)Falls nicht angegeben, wird 022 verwendet\&. Somit werden die Dateien und Verzeichnisse des Benutzers mit dem Modus 755 beziehungsweise dem Zugriffsmuster rwxr\-wr\-x angelegt\&.
.sp
\fBuseradd\fR
and
\fBnewusers\fR
use this mask to set the mode of the home directory they create if
\fBHOME_MODE\fR
is not set\&.
.sp
It is also used by
\fBpam_umask\fR
as the default umask value\&.
.RE
.PP
\fBUSERDEL_CMD\fR (string)
.RS 4
falls angegeben, wird dieser Befehl ausgef\(:uhrt, wenn ein Benutzer entfernt wird\&. Damit k\(:onnen At\-, Cron\- und Druckauftr\(:age etc\&. des Benutzers (sein Name ist als erstes Argument zu \(:ubergeben) gel\(:oscht werden\&.
.sp
Der R\(:uckgabewert des Skripts bleibt unber\(:ucksichtigt\&.
.sp
Here is an example script, which removes the user\*(Aqs cron, at and print jobs:
.sp
.if n \{\
.RS 4
.\}
.nf
#! /bin/sh

# Check for the required argument\&.
if [ $# != 1 ]; then
	echo "Usage: $0 username"
	exit 1
fi

# Remove cron jobs\&.
crontab \-r \-u $1

# Remove at jobs\&.
# Note that it will remove any jobs owned by the same UID,
# even if it was shared by a different username\&.
AT_SPOOL_DIR=/var/spool/cron/atjobs
find $AT_SPOOL_DIR \-name "[^\&.]*" \-type f \-user $1 \-delete \e;

# Remove print jobs\&.
lprm $1

# All done\&.
exit 0
      
.fi
.if n \{\
.RE
.\}
.sp
.RE
.PP
\fBUSERGROUPS_ENAB\fR (boolean)
.RS 4
If set to
\fIyes\fR,
\fBuserdel\fR
will remove the user\*(Aqs group if it contains no more members, and
\fBuseradd\fR
will create by default a group with the name of the user\&.
.RE
.PP
\fBYESCRYPT_COST_FACTOR\fR (number)
.RS 4
When
\fBENCRYPT_METHOD\fR
is set to
\fIYESCRYPT\fR, this defines the cost factor used by the encryption algorithm by default (when the cost factor is not specified on the command line)\&.
.sp
With a high cost factor, it is more difficult to brute force the password\&. But note also that more CPU resources will be needed to authenticate users\&.
.sp
The value must be inside the 1\-11 range\&.
.sp
Note: this only affect the generation of group passwords\&. The generation of user passwords is done by PAM and subject to the PAM configuration\&. It is recommended to set this variable consistently with the PAM configuration\&.
.RE
.SH "QUERVERWEISE"
.PP
Die folgenden Querverweise zeigen, welche Programme aus der Shadow\-Passwort\-Sammlung welche Parameter verwenden\&.
.PP
chfn
.RS 4
CHFN_RESTRICT
.RE
.PP
chgpasswd
.RS 4
ENCRYPT_METHOD MAX_MEMBERS_PER_GROUP SHA_CRYPT_MAX_ROUNDS SHA_CRYPT_MIN_ROUNDS
YESCRYPT_COST_FACTOR
.RE
.PP
chpasswd
.RS 4
SHA_CRYPT_MAX_ROUNDS SHA_CRYPT_MIN_ROUNDS
YESCRYPT_COST_FACTOR
.RE
.PP
gpasswd
.RS 4
ENCRYPT_METHOD MAX_MEMBERS_PER_GROUP SHA_CRYPT_MAX_ROUNDS SHA_CRYPT_MIN_ROUNDS
YESCRYPT_COST_FACTOR
.RE
.PP
groupadd
.RS 4
GID_MAX GID_MIN MAX_MEMBERS_PER_GROUP SYS_GID_MAX SYS_GID_MIN
.RE
.PP
groupdel
.RS 4
MAX_MEMBERS_PER_GROUP
.RE
.PP
groupmod
.RS 4
MAX_MEMBERS_PER_GROUP
.RE
.PP
grpck
.RS 4
MAX_MEMBERS_PER_GROUP
.RE
.PP
grpconv
.RS 4
MAX_MEMBERS_PER_GROUP
.RE
.PP
grpunconv
.RS 4
MAX_MEMBERS_PER_GROUP
.RE
.PP
lastlog
.RS 4
LASTLOG_UID_MAX
.RE
.PP
newgrp / sg
.RS 4
SYSLOG_SG_ENAB
.RE
.PP
newusers
.RS 4
ENCRYPT_METHOD GID_MAX GID_MIN MAX_MEMBERS_PER_GROUP HOME_MODE PASS_MAX_DAYS PASS_WARN_AGE SHA_CRYPT_MAX_ROUNDS SHA_CRYPT_MIN_ROUNDS SUB_GID_COUNT SUB_GID_MAX SUB_GID_MIN SUB_GID_DETERMINISTIC SUB_GID_STORE_BY_UID SUB_UID_COUNT SUB_UID_MAX SUB_UID_MIN SUB_UID_DETERMINISTIC SUB_UID_STORE_BY_UID SYS_GID_MAX SYS_GID_MIN SYS_UID_MAX SYS_UID_MIN UID_MAX UID_MIN UMASK UNSAFE_SUB_GID_DETERMINISTIC_WRAP UNSAFE_SUB_UID_DETERMINISTIC_WRAP
YESCRYPT_COST_FACTOR
.RE
.PP
pwck
.RS 4
PASS_MAX_DAYS PASS_WARN_AGE
.RE
.PP
pwconv
.RS 4
PASS_MAX_DAYS PASS_WARN_AGE
.RE
.PP
useradd
.RS 4
CREATE_HOME GID_MAX GID_MIN HOME_MODE LASTLOG_UID_MAX MAIL_DIR MAX_MEMBERS_PER_GROUP PASS_MAX_DAYS PASS_WARN_AGE SUB_GID_COUNT SUB_GID_MAX SUB_GID_MIN SUB_GID_DETERMINISTIC SUB_GID_STORE_BY_UID SUB_UID_COUNT SUB_UID_MAX SUB_UID_MIN SUB_UID_DETERMINISTIC SUB_UID_STORE_BY_UID SYS_GID_MAX SYS_GID_MIN SYS_UID_MAX SYS_UID_MIN UID_MAX UID_MIN UMASK UNSAFE_SUB_GID_DETERMINISTIC_WRAP UNSAFE_SUB_UID_DETERMINISTIC_WRAP
.RE
.PP
userdel
.RS 4
MAIL_DIR MAIL_FILE MAX_MEMBERS_PER_GROUP USERDEL_CMD USERGROUPS_ENAB
.RE
.PP
usermod
.RS 4
LASTLOG_UID_MAX MAIL_DIR MAIL_FILE MAX_MEMBERS_PER_GROUP SUB_GID_COUNT SUB_GID_MAX SUB_GID_MIN SUB_GID_DETERMINISTIC SUB_UID_COUNT SUB_UID_MAX SUB_UID_MIN SUB_UID_DETERMINISTIC UNSAFE_SUB_GID_DETERMINISTIC_WRAP UNSAFE_SUB_UID_DETERMINISTIC_WRAP
.RE
.SH "FEHLER"
.PP
Much of the functionality that used to be provided by the shadow password suite is now handled by PAM\&. Thus,
/etc/login\&.defs
is no longer used by
\fBpasswd\fR(1), or less used by
\fBlogin\fR(1), and
\fBsu\fR(1)\&. Please refer to the corresponding PAM configuration files instead\&.
.SH "SIEHE AUCH"
.PP
\fBlogin\fR(1),
\fBpasswd\fR(1),
\fBsu\fR(1),
\fBpasswd\fR(5),
\fBshadow\fR(5),
\fBpam\fR(8)\&.