'\" t
.\"     Title: subgid
.\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: 05/17/2017
.\"    Manual: File Formats and Conversions
.\"    Source: shadow-utils 4.2
.\"  Language: English
.\"
.TH "SUBGID" "5" "05/17/2017" "shadow\-utils 4\&.2" "File Formats and Conversions"
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.SH "NAME"
subgid \- the subordinate gid file
.SH "DESCRIPTION"
.PP
Each line in
/etc/subgid
contains a user name and a range of subordinate group ids that user is allowed to use\&. This is specified with three fields delimited by colons (\(lq:\(rq)\&. These fields are:
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
login name
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
numerical subordinate group ID
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
numerical subordinate group ID count
.RE
.PP
This file specifies the group IDs that ordinary users can use, with the
\fBnewgidmap\fR
command, to configure gid mapping in a user namespace\&.
.PP
Multiple ranges may be specified per user\&.
.SH "FILES"
.PP
/etc/subgid
.RS 4
Per user subordinate group IDs\&.
.RE
.PP
/etc/subgid\-
.RS 4
Backup file for /etc/subgid\&.
.RE
.SH "SEE ALSO"
.PP
\fBlogin.defs\fR(5),
\fBnewgidmap\fR(1),
\fBnewuidmap\fR(1),
\fBnewusers\fR(8),
\fBsubuid\fR(5),
\fBuseradd\fR(8),
\fBuserdel\fR(8),
\fBusermod\fR(8),
\fBuser_namespaces\fR(7)\&.