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# SOME DESCRIPTIVE TITLE
# Copyright (C) YEAR Free Software Foundation, Inc.
# This file is distributed under the same license as the PACKAGE package.
# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
#
#, fuzzy
msgid ""
msgstr ""
"Project-Id-Version: PACKAGE VERSION\n"
"POT-Creation-Date: 2024-06-01 05:44+0200\n"
"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
"Language: \n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"

#. type: TH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "cgroup_namespaces"
msgstr ""

#. type: TH
#: archlinux debian-unstable opensuse-tumbleweed
#, no-wrap
msgid "2024-05-02"
msgstr ""

#. type: TH
#: archlinux debian-unstable
#, no-wrap
msgid "Linux man-pages 6.8"
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "NAME"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid "cgroup_namespaces - overview of Linux cgroup namespaces"
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "DESCRIPTION"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid "For an overview of namespaces, see B<namespaces>(7)."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Cgroup namespaces virtualize the view of a process's cgroups (see "
"B<cgroups>(7))  as seen via I</proc/>pidI</cgroup> and I</proc/>pidI</"
"mountinfo>."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Each cgroup namespace has its own set of cgroup root directories.  These "
"root directories are the base points for the relative locations displayed in "
"the corresponding records in the I</proc/>pidI</cgroup> file.  When a "
"process creates a new cgroup namespace using B<clone>(2)  or B<unshare>(2)  "
"with the B<CLONE_NEWCGROUP> flag, its current cgroups directories become the "
"cgroup root directories of the new namespace.  (This applies both for the "
"cgroups version 1 hierarchies and the cgroups version 2 unified hierarchy.)"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"When reading the cgroup memberships of a \"target\" process from I</proc/"
">pidI</cgroup>, the pathname shown in the third field of each record will be "
"relative to the reading process's root directory for the corresponding "
"cgroup hierarchy.  If the cgroup directory of the target process lies "
"outside the root directory of the reading process's cgroup namespace, then "
"the pathname will show I<../> entries for each ancestor level in the cgroup "
"hierarchy."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The following shell session demonstrates the effect of creating a new cgroup "
"namespace."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"First, (as superuser) in a shell in the initial cgroup namespace, we create "
"a child cgroup in the I<freezer> hierarchy, and place a process in that "
"cgroup that we will use as part of the demonstration below:"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid ""
"# B<mkdir -p /sys/fs/cgroup/freezer/sub2>\n"
"# B<sleep 10000 &>     # Create a process that lives for a while\n"
"[1] 20124\n"
"# B<echo 20124 E<gt> /sys/fs/cgroup/freezer/sub2/cgroup.procs>\n"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"We then create another child cgroup in the I<freezer> hierarchy and put the "
"shell into that cgroup:"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid ""
"# B<mkdir -p /sys/fs/cgroup/freezer/sub>\n"
"# B<echo $$>                      # Show PID of this shell\n"
"30655\n"
"# B<echo 30655 E<gt> /sys/fs/cgroup/freezer/sub/cgroup.procs>\n"
"# B<cat /proc/self/cgroup | grep freezer>\n"
"7:freezer:/sub\n"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Next, we use B<unshare>(1)  to create a process running a new shell in new "
"cgroup and mount namespaces:"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "# B<PS1=\"sh2# \" unshare -Cm bash>\n"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"From the new shell started by B<unshare>(1), we then inspect the I</proc/"
">pidI</cgroup> files of, respectively, the new shell, a process that is in "
"the initial cgroup namespace (I<init>, with PID 1), and the process in the "
"sibling cgroup (I<sub2>):"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid ""
"sh2# B<cat /proc/self/cgroup | grep freezer>\n"
"7:freezer:/\n"
"sh2# B<cat /proc/1/cgroup | grep freezer>\n"
"7:freezer:/..\n"
"sh2# B<cat /proc/20124/cgroup | grep freezer>\n"
"7:freezer:/../sub2\n"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"From the output of the first command, we see that the freezer cgroup "
"membership of the new shell (which is in the same cgroup as the initial "
"shell)  is shown defined relative to the freezer cgroup root directory that "
"was established when the new cgroup namespace was created.  (In absolute "
"terms, the new shell is in the I</sub> freezer cgroup, and the root "
"directory of the freezer cgroup hierarchy in the new cgroup namespace is "
"also I</sub>.  Thus, the new shell's cgroup membership is displayed as "
"\\[aq]/\\[aq].)"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"However, when we look in I</proc/self/mountinfo> we see the following "
"anomaly:"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid ""
"sh2# B<cat /proc/self/mountinfo | grep freezer>\n"
"155 145 0:32 /.. /sys/fs/cgroup/freezer ...\n"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The fourth field of this line (I</..>)  should show the directory in the "
"cgroup filesystem which forms the root of this mount.  Since by the "
"definition of cgroup namespaces, the process's current freezer cgroup "
"directory became its root freezer cgroup directory, we should see \\[aq]/"
"\\[aq] in this field.  The problem here is that we are seeing a mount entry "
"for the cgroup filesystem corresponding to the initial cgroup namespace "
"(whose cgroup filesystem is indeed rooted at the parent directory of "
"I<sub>).  To fix this problem, we must remount the freezer cgroup filesystem "
"from the new shell (i.e., perform the mount from a process that is in the "
"new cgroup namespace), after which we see the expected results:"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid ""
"sh2# B<mount --make-rslave />     # Don\\[aq]t propagate mount events\n"
"                               # to other namespaces\n"
"sh2# B<umount /sys/fs/cgroup/freezer>\n"
"sh2# B<mount -t cgroup -o freezer freezer /sys/fs/cgroup/freezer>\n"
"sh2# B<cat /proc/self/mountinfo | grep freezer>\n"
"155 145 0:32 / /sys/fs/cgroup/freezer rw,relatime ...\n"
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "STANDARDS"
msgstr ""

#. type: Plain text
#: archlinux debian-unstable fedora-40 fedora-rawhide mageia-cauldron
#: opensuse-leap-15-6 opensuse-tumbleweed
msgid "Linux."
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "NOTES"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"Use of cgroup namespaces requires a kernel that is configured with the "
"B<CONFIG_CGROUPS> option."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"The virtualization provided by cgroup namespaces serves a number of purposes:"
msgstr ""

#. type: IP
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "\\[bu]"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"It prevents information leaks whereby cgroup directory paths outside of a "
"container would otherwise be visible to processes in the container.  Such "
"leakages could, for example, reveal information about the container "
"framework to containerized applications."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"It eases tasks such as container migration.  The virtualization provided by "
"cgroup namespaces allows containers to be isolated from knowledge of the "
"pathnames of ancestor cgroups.  Without such isolation, the full cgroup "
"pathnames (displayed in I</proc/self/cgroups>)  would need to be replicated "
"on the target system when migrating a container; those pathnames would also "
"need to be unique, so that they don't conflict with other pathnames on the "
"target system."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"It allows better confinement of containerized processes, because it is "
"possible to mount the container's cgroup filesystems such that the container "
"processes can't gain access to ancestor cgroup directories.  Consider, for "
"example, the following scenario:"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid "We have a cgroup directory, I</cg/1>, that is owned by user ID 9000."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"We have a process, I<X>, also owned by user ID 9000, that is namespaced "
"under the cgroup I</cg/1/2> (i.e., I<X> was placed in a new cgroup namespace "
"via B<clone>(2)  or B<unshare>(2)  with the B<CLONE_NEWCGROUP> flag)."
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"In the absence of cgroup namespacing, because the cgroup directory I</cg/1> "
"is owned (and writable) by UID 9000 and process I<X> is also owned by user "
"ID 9000, process I<X> would be able to modify the contents of cgroups files "
"(i.e., change cgroup settings) not only in I</cg/1/2> but also in the "
"ancestor cgroup directory I</cg/1>.  Namespacing process I<X> under the "
"cgroup directory I</cg/1/2>, in combination with suitable mount operations "
"for the cgroup filesystem (as shown above), prevents it modifying files in "
"I</cg/1>, since it cannot even see the contents of that directory (or of "
"further removed cgroup ancestor directories).  Combined with correct "
"enforcement of hierarchical limits, this prevents process I<X> from escaping "
"the limits imposed by ancestor cgroups."
msgstr ""

#. type: SH
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
#, no-wrap
msgid "SEE ALSO"
msgstr ""

#. type: Plain text
#: archlinux debian-bookworm debian-unstable fedora-40 fedora-rawhide
#: mageia-cauldron opensuse-leap-15-6 opensuse-tumbleweed
msgid ""
"B<unshare>(1), B<clone>(2), B<setns>(2), B<unshare>(2), B<proc>(5), "
"B<cgroups>(7), B<credentials>(7), B<namespaces>(7), B<user_namespaces>(7)"
msgstr ""

#. type: TH
#: debian-bookworm
#, no-wrap
msgid "2023-02-05"
msgstr ""

#. type: TH
#: debian-bookworm
#, no-wrap
msgid "Linux man-pages 6.03"
msgstr ""

#. type: Plain text
#: debian-bookworm
msgid "Namespaces are a Linux-specific feature."
msgstr ""

#. type: TH
#: fedora-40 fedora-rawhide mageia-cauldron
#, no-wrap
msgid "2023-10-31"
msgstr ""

#. type: TH
#: fedora-40 mageia-cauldron
#, no-wrap
msgid "Linux man-pages 6.06"
msgstr ""

#. type: TH
#: fedora-rawhide
#, no-wrap
msgid "Linux man-pages 6.7"
msgstr ""

#. type: TH
#: opensuse-leap-15-6
#, no-wrap
msgid "2023-03-30"
msgstr ""

#. type: TH
#: opensuse-leap-15-6
#, no-wrap
msgid "Linux man-pages 6.04"
msgstr ""

#. type: TH
#: opensuse-tumbleweed
#, no-wrap
msgid "Linux man-pages (unreleased)"
msgstr ""