X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd-nspawn.xml;h=b3a2d328559273a6feccc01114ca7e562e419e98;hp=8f92b8430461ce2efd6216df824255a048cd9956;hb=9700d6980f7c212b10a69399e6430b82a6f45587;hpb=db999e0f923ca6c2c1b919d0f1c916472f209e62 diff --git a/man/systemd-nspawn.xml b/man/systemd-nspawn.xml index 8f92b8430..b3a2d3285 100644 --- a/man/systemd-nspawn.xml +++ b/man/systemd-nspawn.xml @@ -21,7 +21,8 @@ along with systemd; If not, see . --> - + systemd-nspawn @@ -69,7 +70,7 @@ systemd-nspawn may be used to run a command or OS in a light-weight namespace container. In many ways it is similar to - chroot1, + chroot1, but more powerful since it fully virtualizes the file system hierarchy, as well as the process tree, the various IPC subsystems and the host and domain @@ -97,15 +98,15 @@ involved with boot and systems management. In contrast to - chroot1 systemd-nspawn + chroot1 systemd-nspawn may be used to boot full Linux-based operating systems in a container. Use a tool like - yum8, - debootstrap8, + yum8, + debootstrap8, or - pacman8 + pacman8 to set up an OS directory tree suitable as file system hierarchy for systemd-nspawn containers. @@ -135,8 +136,9 @@ As a safety check systemd-nspawn will verify the - existence of /etc/os-release in - the container tree before starting the container (see + existence of /usr/lib/os-release + or /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 @@ -158,30 +160,44 @@ The following options are understood: - - - - - Prints a short help - text and exits. - - - - - - Prints a version string - and exits. - - Directory to use as - file system root for the namespace - container. If omitted, the current - directory will be - used. + file system root for the container. If + neither + nor are + specified, the current directory will + be used. May not be specified together with + . + + + + + + + Disk image to mount + the root directory for the container + from. Takes a path to a regular file + or to a block device node. The file or + block device must contain a GUID + Partition Table with a root partition + which is mounted as the root directory + of the container. Optionally, it may + contain a home and/or a server data + partition which are mounted to the + appropriate places in the + container. All these partitions must + be identified by the partition types + defined by the Discoverable + Partitions Specification. Any + other partitions, such as foreign + partitions, swap partitions or EFI + system partitions are not mounted. May + not be specified together with + . @@ -204,13 +220,15 @@ - Run the command - under specified user, create home - directory and cd into it. As rest - of systemd-nspawn, this is not - the security feature and limits - against accidental changes only. - + After transitioning + into the container, change to the + specified user-defined in the + container's user database. Like all + other systemd-nspawn features, this is + not a security feature and provides + protection against accidental + destructive operations + only. @@ -228,16 +246,125 @@ container is used. + + + + Set the specified UUID + for the container. The init system + will initialize + /etc/machine-id + from this if this file is not set yet. + + + Make the container part of the specified slice, instead - of the + of the default machine.slice. + + + + 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 + . + + + + + + Assign the specified + network interface to the + container. This will remove 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 + macvlan interface + of the specified Ethernet network + interface and add it to the + container. A + macvlan interface + is a virtual interface that adds a + second MAC address to an existing + physical Ethernet link. The interface + in the container will be named after + the interface on the host, prefixed + with mv-. Note that + + implies + . This + option may be used more than once to + add multiple network interfaces to the + container. + + + + + + Create a virtual + Ethernet link + (veth) 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 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 + . If + this option is used, the host side of + the Ethernet link will use the + vb- prefix instead + of ve-. + + @@ -259,35 +386,6 @@ - - - - Set the specified UUID - for the container. The init system - will initialize - /etc/machine-id - from this if this file is not set yet. - - - - - - - Turn off networking in - the container. This makes all network - interfaces unavailable in the - container, with the exception of the - loopback device. - - - - - - Mount the root file - system read-only for the - container. - - @@ -295,7 +393,7 @@ additional capabilities to grant the container. Takes a comma-separated list of capability names, see - capabilities7 + capabilities7 for more information. Note that the following capabilities will be granted in any way: CAP_CHOWN, @@ -311,7 +409,13 @@ CAP_SYS_PTRACE, CAP_SYS_TTY_CONFIG, CAP_SYS_RESOURCE, CAP_SYS_BOOT, CAP_AUDIT_WRITE, - CAP_AUDIT_CONTROL. + CAP_AUDIT_CONTROL. Also CAP_NET_ADMIN + is retained if + is + specified. If the special value + all is passed, all + capabilities are + retained. @@ -372,6 +476,14 @@ . + + + + Mount the root file + system read-only for the + container. + + @@ -389,7 +501,31 @@ destination in the container. The option creates read-only bind - mount. + mounts. + + + + + + Mount a tmpfs file + system into the container. Takes a + single absolute path argument that + specifies where to mount the tmpfs + instance to (in which case the + directory access mode will be chosen + as 0755, owned by root/root), or + optionally a colon-separated pair of + path and mount option string, that is + used for mounting (in which case the + kernel default for access mode and + owner will be chosen, unless otherwise + specified). This option is + particularly useful for mounting + directories such as + /var as tmpfs, to + allow state-less systems, in + particular when combined with + . @@ -406,17 +542,6 @@ more than once. - - - - - Turns off any status - output by the tool itself. When this - switch is used, then the only output - by nspawn will be the console output - of the container OS itself. - - @@ -456,9 +581,9 @@ accessible via machinectl1 and shown by tools such as - ps1. If + ps1. If the container does not run an init - system it is recommended to set this + system, it is recommended to set this option to no. Note that implies @@ -474,13 +599,13 @@ container in, simply register the service or scope unit systemd-nspawn has - been invoked in in + 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 an a service unit, + invoked from within a service unit, and the service unit's sole purpose is to run a single systemd-nspawn @@ -489,74 +614,150 @@ 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 32-bit container on a 64-bit + host. If this setting is not used, + the personality reported in the + container is the same as the one + reported on the + host. + + + + + + + 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. + + + + =MODE + + Boots the container in + volatile (ephemeral) mode. When no + mode parameter is passed or when mode + is specified as yes + full volatile mode is enabled. This + means the root directory is mounted as + mostly unpopulated + tmpfs instance, and + /usr from the OS + tree is mounted into it, read-only + (the system thus starts up with + read-only OS resources, but pristine + state and configuration, any changes + to the either are lost on + shutdown). When the mode parameter is + specified as state + the OS tree is mounted read-only, but + /var is mounted + as tmpfs instance + into it (the system thus starts up + with read-only OS resources and + configuration, but pristine state, any + changes to the latter are lost on + shutdown). When the mode parameter is + specified as no + (the default) the whole OS tree is made + available writable. + + Note that setting this to + yes or + state will only + work correctly with operating systems + in the container that can boot up with + only /usr + mounted, and are able to populate + /var + automatically, as + needed. + + + + - Example 1 + Examples + + Boot a minimal Fedora distribution in a container - # yum -y --releasever=19 --nogpg --installroot=/srv/mycontainer --disablerepo='*' --enablerepo=fedora install systemd passwd yum fedora-release vim-minimal + # 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 /srv/mycontainer/ and - then boots an OS in a namespace container in - it. - + This installs a minimal Fedora distribution into + the directory /srv/mycontainer/ and + then boots an OS in a namespace container in + it. + - - Example 2 + + Spawn a shell in a container of a minimal Debian unstable distribution - # debootstrap --arch=amd64 unstable ~/debian-tree/ + # debootstrap --arch=amd64 unstable ~/debian-tree/ # systemd-nspawn -D ~/debian-tree/ - This installs a minimal Debian unstable - distribution into the directory - ~/debian-tree/ and then spawns a - shell in a namespace container in it. - + This installs a minimal Debian unstable + distribution into the directory + ~/debian-tree/ and then spawns a + shell in a namespace container in it. + - - Example 3 + + Boot a minimal Arch Linux distribution in a container - # pacstrap -c -d ~/arch-tree/ base + # 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. - + 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 + + Enable Arch Linux container on boot - # mv ~/arch-tree /var/lib/container/arch + # 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. - - + This makes the Arch Linux container part of the + multi-user.target on the host. + + - - Example 5 + + Boot into a btrfs snapshot of the host system - # btrfs subvolume snapshot / /.tmp + # btrfs subvolume snapshot / /.tmp # systemd-nspawn --private-network -D /.tmp -b - This runs a copy of the host system in a - btrfs snapshot. - + This runs a copy of the host system in a + btrfs snapshot. + - - Example 6 + + Run a container with SELinux sandbox security contexts - # chcon system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 -R /srv/container + # 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. + @@ -570,10 +771,10 @@ See Also systemd1, - chroot1, - yum8, - debootstrap8, - pacman8, + chroot1, + yum8, + debootstrap8, + pacman8, systemd.slice5, machinectl1