SUBUID(5) File Formats and Conversions SUBUID(5)NAME
subuid - the subordinate uid file
DESCRIPTION
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:
o login name or UID
o numerical subordinate user ID
o 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.
FILES
/etc/subuid
Per user subordinate user IDs.
/etc/subuid-
Backup file for /etc/subuid.
SEE ALSO login.defs(5), newgidmap(1), newuidmap(1), newusers(1), subgid(5), useradd(8), userdel(8), usermod(8), user_namespaces(7).
shadow-utils 4.5 01/25/2018 SUBUID(5)
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SUBUID(5) File Formats and Conversions SUBUID(5)NAME
subuid - the subordinate uid file
DESCRIPTION
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:
o login name or UID
o numerical subordinate user ID
o 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.
FILES
/etc/subuid
Per user subordinate user IDs.
/etc/subuid-
Backup file for /etc/subuid.
SEE ALSO login.defs(5), newgidmap(1), newuidmap(1), newusers(1), subgid(5), useradd(8), userdel(8), usermod(8), user_namespaces(7).
shadow-utils 4.5 01/25/2018 SUBUID(5)
What is the point of this? Whenever I close my shell it appends to the history file without adding this. I have never seen it overwrite my history file.
# When the shell exits, append to the history file instead of overwriting it
shopt -s histappend (3 Replies)