SUBUID(5) File Formats and Conversions SUBUID(5)
subuid - the subordinate uid file
Each line in /etc/subuid contains a user name and a range of subordinate user ids that user is allowed to use. This is specified with three fields delimited by colons (“:”). These fields are: · login name or UID · numerical subordinate user ID · numerical subordinate user ID count This file specifies the user IDs that ordinary users can use, with the newuidmap command, to configure uid mapping in a user namespace. Multiple ranges may be specified per user. When large number of entries (10000-100000 or more) are defined in /etc/subuid, parsing performance penalty will become noticeable. In this case it is recommended to use UIDs instead of login names. Benchmarks have shown speed-ups up to 20x.
/etc/subuid Per user subordinate user IDs. /etc/subuid- Backup file for /etc/subuid.
login.defs(5), newgidmap(1), newuidmap(1), newusers(1), subgid(5), useradd(8), userdel(8), usermod(8), user_namespaces(7).
This page is part of the shadow-utils (utilities for managing accounts and shadow password files) project. Information about the project can be found at ⟨https://github.com/shadow-maint/shadow⟩. If you have a bug report for this manual page, send it to email@example.com. This page was obtained from the project's upstream Git repository ⟨https://github.com/shadow-maint/shadow⟩ on 2020-08-13. (At that time, the date of the most recent commit that was found in the repos‐ itory was 2020-08-13.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to firstname.lastname@example.org shadow-utils 4.8.1 08/13/2020 SUBUID(5)
Pages that refer to this page: newuidmap(1), subgid(5), user_namespaces(7), newusers(8), useradd(8), userdel(8), usermod(8)