X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd-nspawn.xml;h=8396def003e59b3b61f793938ec6a7ab0108804b;hp=66d2c6b69a749ed422c68456a16287f4c0ce3ecf;hb=cb96a2c69a312fb089fef4501650f4fc40a1420b;hpb=0cd1fd4369685b10953ada832a0b505f5732667d diff --git a/man/systemd-nspawn.xml b/man/systemd-nspawn.xml index 66d2c6b69..8396def00 100644 --- a/man/systemd-nspawn.xml +++ b/man/systemd-nspawn.xml @@ -49,7 +49,10 @@ - systemd-nspawn OPTIONS COMMAND ARGS + systemd-nspawn + OPTIONS + COMMAND + ARGS @@ -93,9 +96,10 @@ container. Use a tool like - yum8 - or + yum8, debootstrap8 + or + pacman8 to set up an OS directory tree suitable as file system hierarchy for systemd-nspawn containers. @@ -113,7 +117,10 @@ 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. It is however possible to + enter an existing container, see + Example 4 below. + systemd-nspawn implements the - + Prints a short help text and exits. - + + + Prints a version string + and exits. + + + + Directory to use as file system root for the namespace @@ -150,18 +164,20 @@ - + Automatically search for an init binary and invoke it instead of a shell or a user supplied - program. + program. A command to execute cannot + be specified in this case. + - + Run the command under specified user, create home @@ -184,8 +200,8 @@ - + Makes the container appear in other hierarchies than the name=systemd:/ one. @@ -220,8 +236,8 @@ list of capability names, see capabilities7 for more information. Note that the - 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 +248,9 @@ 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. @@ -248,31 +266,30 @@ host, guest, auto. If - no the journal is - not linked. If host + no, the journal is + not linked. If host, the journal files are stored on the - host file system (beneath the host's - /var/log/journal) - and a per-machine subdirectory of this - directory is created and bind mounted + host file system (beneath + /var/log/journal/machine-id) + and the subdirectory is bind-mounted into the container at the same - location. If guest + location. If guest, the journal files are stored on the - guest file system (beneath the guest's - /var/log/journal) - and a per-machine subdirectory of this - directory is symlinked into the host + 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) - and the subdirectory of + auto (the default), + and the right subdirectory of /var/log/journal - exists as directory it is bind mounted - into the container, but nothing is - done otherwise. Effectively, booting a - container once with + exists, it will be bind mounted + into the container. If the + subdirectory doesn't exist, no + linking is performed. Effectively, + booting a container once with guest or host will link the - journal persistantly if further one + journal persistently if further on the default of auto is used. @@ -290,13 +307,13 @@ 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. @@ -309,7 +326,35 @@ 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 + + To enter the container, PID of one of the + processes sharing the new namespaces must be used. + systemd-nspawn prints the PID + (as viewed from the outside) of the launched process, + and it can be used to enter the container. + + # nsenter -muinpt $PID + nsenter1 + is part of + util-linux. + Kernel support for entering namespaces was added in + Linux 3.8. @@ -324,8 +369,10 @@ systemd1, chroot1, + unshare1, yum8, - debootstrap8 + debootstrap8, + pacman8