X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd-nspawn.xml;h=fa0680ffcddba7ce3d271192eef6e648f2db6218;hp=b3a2d328559273a6feccc01114ca7e562e419e98;hb=f131770b1465fbf423881f16ba85523a05f846fe;hpb=c45827d6e70baf6b683d7cafb13a9a6f02852731 diff --git a/man/systemd-nspawn.xml b/man/systemd-nspawn.xml index b3a2d3285..fa0680ffc 100644 --- a/man/systemd-nspawn.xml +++ b/man/systemd-nspawn.xml @@ -165,14 +165,80 @@ Directory to use as - file system root for the container. If - neither - nor are + file system root for the container. + + If neither + , nor + is specified + the directory is determined as + /var/lib/container/ + suffixed by the machine name as + specified with + . If + neither , + , nor + are specified, the current directory will - be used. May not be specified together with + be used. May not be specified together + with . + + + + Directory or + btrfs subvolume to + use as template for the container's + root directory. If this is specified + and the container's root directory (as + configured by + ) does + not yet exist it is created as + btrfs subvolume and + populated from this template + tree. Ideally, the specified template + path refers to the root of a + btrfs subvolume, in + which case a simple copy-on-write + snapshot is taken, and populating the + root directory is instant. If the + specified template path does not refer + to the root of a + btrfs subvolume (or + not even to a btrfs + file system at all), the tree is + copied, which can be substantially + more time-consuming. Note that if this + option is used the container's root + directory (in contrast to the template + directory!) must be located on a + btrfs file system, + so that the btrfs + subvolume may be created. May not be + specified together with + or + . + + + + + + + If specified, the + container is run with a temporary + btrfs snapshot of + its root directory (as configured with + ), that + is removed immediately when the + container terminates. This option is + only supported if the root file system + is btrfs. May not + be specified together with + or + . + + @@ -197,7 +263,9 @@ partitions, swap partitions or EFI system partitions are not mounted. May not be specified together with - . + , + or + . @@ -237,13 +305,22 @@ 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. + used to identify this container during + its runtime (for example in tools like + machinectl1 + and similar), 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 path of the container is + used, possibly suffixed with a random + identifier in case + mode is + selected. If the root directory + selected is the host's root directory + the host's hostname is used as default + instead. @@ -439,7 +516,9 @@ versa). Takes one of no, host, + try-host, guest, + try-guest, auto. If no, the journal is not linked. If host, @@ -453,8 +532,11 @@ guest file system (beneath /var/log/journal/machine-id) and the subdirectory is symlinked into the host - at the same location. If - auto (the default), + at the same location. try-host + and try-guest do the same + but do not fail if the host does not have + persistent journalling enabled. + If auto (the default), and the right subdirectory of /var/log/journal exists, it will be bind mounted @@ -473,7 +555,7 @@ Equivalent to - . + . @@ -648,13 +730,13 @@ =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 + volatile 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 @@ -672,8 +754,8 @@ 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. + (the default) the whole OS tree is + made available writable. Note that setting this to yes or @@ -698,7 +780,7 @@ 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=21 --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 @@ -743,13 +825,16 @@ - Boot into a btrfs snapshot of the host system + Boot into an ephemeral <literal>btrfs</literal> snapshot of the host system - # btrfs subvolume snapshot / /.tmp -# systemd-nspawn --private-network -D /.tmp -b + # systemd-nspawn -D / -xb This runs a copy of the host system in a - btrfs snapshot. + btrfs snapshot which is + removed immediately when the container + exits. All file system changes made during + runtime will be lost on shutdown, + hence. @@ -776,7 +861,8 @@ debootstrap8, pacman8, systemd.slice5, - machinectl1 + machinectl1, + btrfs8