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diff --git a/manpages/de/persistence.conf.de.5 b/manpages/de/persistence.conf.de.5 new file mode 100644 index 0000000..18e6b4f --- /dev/null +++ b/manpages/de/persistence.conf.de.5 @@ -0,0 +1,207 @@ +.\"******************************************************************* +.\" +.\" This file was generated with po4a. Translate the source file. +.\" +.\"******************************************************************* +.TH LIVE\-BOOT conf 27.09.2012 3.0~b3\-1 "Debian Live Project" + +.SH NAME +\fBpersistence.conf\fP \- Configuration file for persistence media in live\-boot + +.SH DESCRIPTION +If live\-boot probes a persistence volume with the label (or GPT name, or +file name, but from now on we will just say "label") "persistence", that +volume's persistence is fully customizable through the \fBpersistence.conf\fP +file stored on the root of its file system. Any such labeled volume must +have such a file, or it will be ignored. +.PP +The format of \fBpersistence.conf\fP allows empty lines and lines starting with +a "#" (used for comments), both which will be ignored. A so called "custom +mount" has the format: +.PP +.RS +\fIDIR\fP [\fIOPTION\fP]... +.RE +.PP +which roughly translates to "make \fIDIR\fP persistence in the way described by +the list of \fIOPTION\fPs". +.PP +For each custom mount \fIDIR\fP must be an absolute path that cannot contain +white spaces or the special . and .. path components, and cannot be /live +(or any of its sub\-directories). Once activated all changes (file deletion, +creation and modification) to \fIDIR\fP on the live file system are stored +persistently into a path equivalent to \fIDIR\fP on the persistence media, +called the source directory. The default way to achieve persistence is to +simply bind\-mount the corresponding source directory to \fIDIR\fP, but this can +be changed through the use of \fIOPTION\fPs. +.PP +All custom mounts will be done in an order so that no two custom mounts can +"hide" each other. For instance, if we have the two \fIDIR\fP:s /a and /a/b it +would always be the case that /a is mounted first, then /a/b. This remains +true no matter how the lines in \fBpersistence.conf\fP are ordered, or if +several \fBpersistence.conf\fP files on different persistence media are used at +the same time. However, it is forbidden for custom mounts to have their +source directory inside the source directory of another custom mount, so the +source directories that are auto\-created by live\-boot does not support +"nested" mounts like /a and /a/b on the same media. In this case you must +use the \fBsource\fP option (see below) to make sure that they are stored in +different source directories. +.PP +When a source directory doesn't exist on the persistence media for a certain +custom mount, it will be created automatically, and permissions and +ownership will be optimistically set according to \fIDIR\fP. It will also be +bootstrapped by copying the contents of the \fIDIR\fP into its source directory +on the persistence media. The bootstrapping will not happen when the \fBlink\fP +or \fBunion\fP options are used (see below). + +.SH OPTIONS +Custom mounts defined in \fBpersistence.conf\fP accept the following options in +a coma\-separated list: +.IP \fBsource\fP=\fIPATH\fP 4 +When given, store the persistence changes into \fIPATH\fP on the persistence +media. \fIPATH\fP must be a relative path (with respect to the persistence +media root) that cannot contain white spaces or the special . or .. path +components, with the exception that it can be just . which means the +persistence media root. This option is mostly relevant if you want to nest +custom mounts, which otherwise would cause errors, or if you want to make +the whole media root available (similar to the now deprecated \fBhome\-rw\fP +type of persistence). +.PP +The following options are mutually exclusive (only the last given one will +be in effect): +.IP \fBbind\fP 4 +Bind\-mount the source directory to \fIDIR\fP. This is the default. +.IP \fBlink\fP 4 +Create the directory structure of the source directory on the persistence +media in \fIDIR\fP and create symbolic links from the corresponding place in +\fIDIR\fP to each file in the source directory. Existing files or directories +with the same name as any link will be overwritten. Note that deleting the +links in \fIDIR\fP will only remove the link, not the corresponding file in the +source; removed links will reappear after a reboot. To permanently add or +delete a file one must do so directly in the source directory. +.IP +Effectively \fBlink\fP will make only files already in the source directory +persistent, not any other files in \fIDIR\fP. These files must be manually +added to the source directory to make use of this option, and they will +appear in \fIDIR\fP in addition to files already there. This option is useful +when only certain files need to be persistent, not the whole directory +they're in, e.g. some configuration files in a user's home directory. +.IP \fBunion\fP 4 +Save the rw branch of a union on the persistence media, so only the changes +are stored persistently. This can potentially reduce disk usage compared to +bind\-mounts, and will not hide files added to the read\-only media. One +caveat is that the union will use \fIDIR\fP from the image's read\-only file +system, not the real file system root, so files created after boot (e.g. by +live\-config) will not appear in the union. This option will use the union +file system specified by live\-boot's \fBunion\fP boot parameter, but is not +supported with \fBunion=unionmount\fP. + +.SH DIRECTORIES +.IP \fB/live/persistence\fP 4 +All persistence volumes will be mounted here (in a directory corresponding +to the device name). The \fBpersistence.conf\fP file can easily be edited +through this mount, as well as any source directories (which is especially +practical for custom mounts using the \fBlink\fP option). + +.SH EXAMPLES + +Let's say we have a persistence volume \fIVOL\fP with the a \fBpersistence.conf\fP +file containing the following four lines (numbered for ease of reference): +.TP 7 +1. +/home/user1 link,source=config\-files/user1 +.TP +2. +/home/user2 link,source=config\-files/user2 +.TP +3. +/home +.TP +4. +/usr union +.PP +The corresponding source directories are: +.TP 7 +1. +\fIVOL\fP/config\-files/user1 (but it would be \fIVOL\fP/home/user1 without the +\fBsource\fP option) +.TP +2. +\fIVOL\fP/config\-files/user2 (but it would be \fIVOL\fP/home/user2 without the +\fBsource\fP option) +.TP +3. +\fIVOL\fP/home +.TP +4. +\fIVOL\fP/usr +.PP +It was necessary to set the \fBsource\fP options for 1 and 2, since they +otherwise would become nested with 3's source, which is invalid. +.PP +Line 3 will be taken care of before line 1 and 2 in order to prevent custom +mounts 1 and 2 from being hidden by 3. When line 3 is handled, \fIVOL\fP/home +is simply bind\-mounted on /home. To illustrate what happens for lines 1 and +2, let's say that the following files exist: +.TP 7 +a. +\fIVOL\fP/config\-files/user1/.emacs +.TP +b. +\fIVOL\fP/config\-files/user2/.bashrc +.TP +c. +\fIVOL\fP/config\-files/user2/.ssh/config +.PP +Then the following links and directories will be created: +.TP 7 +Link: +/home/user1/.emacs \-> \fIVOL\fP/config\-files/user1/.emacs (from a) +.TP +Link: +/home/user2/.bashrc \-> \fIVOL\fP/config\-files/user2/.bashrc (from b) +.TP +Dir: +/homea/user2/.ssh (from c) +.TP +Link: +/home/user2/.ssh/config \-> \fIVOL\fP/config\-files/user2/.ssh/config (from +c) +.PP +One could argue, though, that lines 1 and 2 in the example +\fBpersistence.conf\fP file above are unnecessary since line 3 already would +make all of /home persistent. The \fBlink\fP option is intended for situations +where you don't want a complete directory to be persistent, only certain +files in it or its sub\-directories. +.PP +Line 4 can be mounted at any time since its \fIDIR\fP (and source directory) is +completely disjoint from all the other custom mounts. When mounted, +\fIVOL\fP/usr will be the rw branch due to the \fBunion\fP option, and will only +contain the difference compared to the underlying read\-only file +system. Hence packages could be installed into /usr with great space\-wise +efficiency compared to bind\-mounts, since in the latter case all of /usr +would have to be copied into \fIVOL\fP/usr during the initial bootstrap. + +.SH "SEE ALSO" +\fIlive\-boot\fP(7) +.PP +\fIlive\-build\fP(7) +.PP +\fIlive\-config\fP(7) +.PP +\fIlive\-tools\fP(7) + +.SH HOMEPAGE +More information about live\-boot and the Debian Live project can be found on +the homepage at <\fIhttp://live.debian.net/\fP> and in the manual at +<\fIhttp://live.debian.net/manual/\fP>. + +.SH BUGS +Bugs can be reported by submitting a bugreport for the live\-boot package in +the Debian Bug Tracking System at <\fIhttp://bugs.debian.org/\fP> or by +writing a mail to the Debian Live mailing list at +<\fIdebian\-live@lists.debian.org\fP>. + +.SH AUTHOR +persistence.conf was written by anonym <\fIanonym@lavabit.com\fP> for +the Debian project. |