X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd-nspawn.xml;h=6518eb819e413979e2db86117e8606f61eb56c82;hp=fef5c2c83a8151336b4069b5ed4f7e9873496f25;hb=6afc95b73605833e6e966af1c466b5c08feb953f;hpb=bb31a4ac1997c189a344caf554f34c6aabc71aa7 diff --git a/man/systemd-nspawn.xml b/man/systemd-nspawn.xml index fef5c2c83..6518eb819 100644 --- a/man/systemd-nspawn.xml +++ b/man/systemd-nspawn.xml @@ -49,7 +49,17 @@ - systemd-nspawn OPTIONS COMMAND ARGS + systemd-nspawn + OPTIONS + COMMAND + ARGS + + + + systemd-nspawn + -b + OPTIONS + ARGS @@ -87,15 +97,15 @@ involved with boot and systems management. In contrast to - chroot1 - systemd-nspawn may be used to boot - full Linux-based operating systems in a - container. + chroot1 systemd-nspawn + may be used to boot full Linux-based operating systems + in a container. Use a tool like - yum8 + yum8, + debootstrap8, or - debootstrap8 + pacman8 to set up an OS directory tree suitable as file system hierarchy for systemd-nspawn containers. @@ -113,55 +123,97 @@ see each other. The PID namespace separation of the two containers is complete and the containers will share very few runtime objects except for the - underlying file system. + underlying file system. Use + machinectl1's + login command to request an + additional login prompt in a running container. systemd-nspawn implements the Container Interface specification. + + As a safety check + systemd-nspawn will verify the + existence of /etc/os-release in + the container tree before starting the container (see + os-release5). It + might be necessary to add this file to the container + tree manually if the OS of the container is too old to + contain this file out-of-the-box. Options - If no arguments are passed the container is set - up and a shell started in it, otherwise the passed - command and arguments are executed in it. The - following options are understood: + If option is specified, the + arguments are used as arguments for the init + binary. Otherwise, COMMAND + specifies the program to launch in the container, and + the remaining arguments are used as arguments for this + program. If is not used and no + arguments are specifed, a shell is launched in the + container. + + The following options are understood: - + Prints a short help text and exits. - + + + Prints a version string + and exits. + + + + + + + Turns off any status + output by the tool itself. When this + switch is used, the only output + from nspawn will be the console output + of the container OS itself. + + + + Directory to use as file system root for the namespace - container. If omitted the current + container. If omitted, the current directory will be used. - + Automatically search for an init binary and invoke it instead of a shell or a user supplied - program. + program. If this option is used, + arguments specified on the command + line are used as arguments for the + init binary. This option may not be + combined with + . + - + Run the command under specified user, create home @@ -172,10 +224,25 @@ + + + + + Sets the machine name + for this container. This name may be + used to identify this container on the + host, and is used to initialize the + container's hostname (which the + container can choose to override, + however). If not specified, the last + component of the root directory of the + container is used. + + - Set the specified uuid + Set the specified UUID for the container. The init system will initialize /etc/machine-id @@ -184,44 +251,117 @@ - - + - Makes the container appear in - other hierarchies than the name=systemd:/ one. - Takes a comma-separated list of controllers. - + Make the container + part of the specified slice, instead + of the default + machine.slice. + - Turn off networking in - the container. This makes all network - interfaces unavailable in the - container, with the exception of the - loopback device. + Disconnect networking + of the container from the host. This + makes all network interfaces + unavailable in the container, with the + exception of the loopback device and + those specified with + + and configured with + . If + this option is specified, the + CAP_NET_ADMIN capability will be added + to the set of capabilities the + container retains. The latter may be + disabled by using + . - - - Mount the root file - system read only for the + + + Assign the specified + network interface to the + container. This will move the + specified interface from the calling + namespace and place it in the + container. When the container + terminates, it is moved back to the + host namespace. Note that + + implies + . This + option may be used more than once to + add multiple network interfaces to the container. + + + + Create a virtual + Ethernet link between host and + container. The host side of the + Ethernet link will be available as a + network interface named after the + container's name (as specified with + ), prefixed + with ve-. The + container side of the the Ethernet + link will be named + host0. Note that + + implies + . + + + + + + Adds the host side of the + Ethernet link created with + + to the specified bridge. Note that + + implies + . + + + + + + + Sets the SELinux + security context to be used to label + processes in the container. + + + + + + + + Sets the SELinux security + context to be used to label files in + the virtual API file systems in the + container. + + + List one or more additional capabilities to grant the - container. Takes a comma separated + container. Takes a comma-separated list of capability names, see capabilities7 for more information. Note that the - following capabilities will be - granted in any way: CAP_CHOWN, + following capabilities will be granted + in any way: CAP_CHOWN, CAP_DAC_OVERRIDE, CAP_DAC_READ_SEARCH, CAP_FOWNER, CAP_FSETID, CAP_IPC_OWNER, CAP_KILL, CAP_LEASE, @@ -232,7 +372,25 @@ CAP_SETUID, CAP_SYS_ADMIN, CAP_SYS_CHROOT, CAP_SYS_NICE, CAP_SYS_PTRACE, CAP_SYS_TTY_CONFIG, - CAP_SYS_RESOURCE, CAP_SYS_BOOT. + CAP_SYS_RESOURCE, CAP_SYS_BOOT, + CAP_AUDIT_WRITE, + CAP_AUDIT_CONTROL. Also CAP_NET_ADMIN + is retained if + is + specified. If the special value + all is passed, all + capabilities are + retained. + + + + + + Specify one or more + additional capabilities to drop for + the container. This allows running the + container with fewer capabilities than + the default (see above). @@ -240,7 +398,7 @@ Control whether the container's journal shall be made - visible to the host system. If enabled + visible to the host system. If enabled, allows viewing the container's journal files from the host (but not vice versa). Takes one of @@ -252,13 +410,13 @@ not linked. If host, the journal files are stored on the host file system (beneath - /var/log/journal/<machine-id>) + /var/log/journal/machine-id) and the subdirectory is bind-mounted into the container at the same location. If guest, the journal files are stored on the guest file system (beneath - /var/log/journal/<machine-id>) + /var/log/journal/machine-id) and the subdirectory is symlinked into the host at the same location. If auto (the default), @@ -266,7 +424,7 @@ /var/log/journal exists, it will be bind mounted into the container. If the - subdirectory doesn't exist, no + subdirectory does not exist, no linking is performed. Effectively, booting a container once with guest or @@ -282,6 +440,139 @@ Equivalent to . + + + + + Mount the root file + system read-only for the + container. + + + + + + + Bind mount a file or + directory from the host into the + container. Either takes a path + argument -- in which case the + specified path will be mounted from + the host to the same path in the + container --, or a colon-separated + pair of paths -- in which case the + first specified path is the source in + the host, and the second path is the + destination in the container. The + option + creates read-only bind + mount. + + + + + + Specifies an + environment variable assignment to + pass to the init process in the + container, in the format + NAME=VALUE. This + may be used to override the default + variables or to set additional + variables. This parameter may be used + more than once. + + + + + + Allows the container + to share certain system facilities + with the host. More specifically, this + turns off PID namespacing, UTS + namespacing and IPC namespacing, and + thus allows the guest to see and + interact more easily with processes + outside of the container. Note that + using this option makes it impossible + to start up a full Operating System in + the container, as an init system + cannot operate in this mode. It is + only useful to run specific programs + or applications this way, without + involving an init system in the + container. This option implies + . This + option may not be combined with + . + + + + + + Controls whether the + container is registered with + systemd-machined8. Takes + a boolean argument, defaults to + yes. This option + should be enabled when the container + runs a full Operating System (more + specifically: an init system), and is + useful to ensure that the container is + accessible via + machinectl1 + and shown by tools such as + ps1. If + the container does not run an init + system, it is recommended to set this + option to no. Note + that + implies + . + + + + + + + Instead of creating a + transient scope unit to run the + container in, simply register the + service or scope unit + systemd-nspawn has + been invoked in with + systemd-machined8. This + has no effect if + is + used. This switch should be used if + systemd-nspawn is + invoked from within a service unit, + and the service unit's sole purpose + is to run a single + systemd-nspawn + container. This option is not + available if run from a user + session. + + + + + + Control the + architecture ("personality") reported + by + uname2 + in the container. Currently, only + x86 and + x86-64 are + supported. This is useful when running + a 32bit container on a 64bit + host. If this setting is not used + the personality reported in the + container is the same as the one + reported on the + host. + @@ -289,13 +580,13 @@ Example 1 - # yum --releasever=17 --nogpgcheck --installroot ~/fedora-tree/ install yum passwd vim-minimal rootfiles systemd -# systemd-nspawn -D ~/fedora-tree /usr/lib/systemd/systemd + # yum -y --releasever=19 --nogpg --installroot=/srv/mycontainer --disablerepo='*' --enablerepo=fedora install systemd passwd yum fedora-release vim-minimal +# systemd-nspawn -bD /srv/mycontainer This installs a minimal Fedora distribution into - the directory ~/fedora-tree/ - and then boots an OS in a namespace container in it, - with systemd as init system. + the directory /srv/mycontainer/ and + then boots an OS in a namespace container in + it. @@ -308,7 +599,48 @@ distribution into the directory ~/debian-tree/ and then spawns a shell in a namespace container in it. + + + + Example 3 + + # pacstrap -c -d ~/arch-tree/ base +# systemd-nspawn -bD ~/arch-tree/ + + This installs a mimimal Arch Linux distribution into + the directory ~/arch-tree/ and then + boots an OS in a namespace container in it. + + + + Example 4 + + # mv ~/arch-tree /var/lib/container/arch +# systemctl enable systemd-nspawn@arch.service +# systemctl start systemd-nspawn@arch.service + + This makes the Arch Linux container part of the + multi-user.target on the host. + + + + + Example 5 + + # btrfs subvolume snapshot / /.tmp +# systemd-nspawn --private-network -D /.tmp -b + + This runs a copy of the host system in a + btrfs snapshot. + + + + Example 6 + + # chcon system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 -R /srv/container +# systemd-nspawn -L system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 -Z system_u:system_r:svirt_lxc_net_t:s0:c0,c1 -D /srv/container /bin/sh + This runs a container with SELinux sandbox security contexts. @@ -324,7 +656,10 @@ systemd1, chroot1, yum8, - debootstrap8 + debootstrap8, + pacman8, + systemd.slice5, + machinectl1