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diff --git a/source/a/mkinitrd/mkinitrd.8.orig b/source/a/mkinitrd/mkinitrd.8.orig new file mode 100644 index 00000000..7e0247a0 --- /dev/null +++ b/source/a/mkinitrd/mkinitrd.8.orig @@ -0,0 +1,287 @@ +.\" -*- nroff -*- +.ds g \" empty +.ds G \" empty +.\" Like TP, but if specified indent is more than half +.\" the current line-length - indent, use the default indent. +.de Tp +.ie \\n(.$=0:((0\\$1)*2u>(\\n(.lu-\\n(.iu)) .TP +.el .TP "\\$1" +.. +.TH MKINITRD 8 "27 March 2010" "Slackware Version 13.1" +.SH NAME +mkinitrd \- create or rebuilt an initrd (initial ramdisk) using initramfs (simple cpio+gzip). +.SH SYNOPSIS +.B mkinitrd +[ +.B \-F +] +[ +.B \-c +] +[ +.B \-f filesystem +] +[ +.B \-h hibernate_partition +] +[ +.B \-k kernel_version +] +[ +.B \-m module1:module2:module3... +] +[ +.B \-o output_file +] +[ +.B \-r root_device +] +[ +.B \-s source_tree +] +[ +.B \-u +] +[ +.B \-w wait_time +] +[ +.B \-C device1:device2:device3... +] +[ +.B \-K luks_keyfile +] +[ +.B \-P microcode_archive +] +[ +.B \-B +] +[ +.B \-L +] +[ +.B \-R +] +[ +.B \-V +] +.SH DESCRIPTION +.B mkinitrd +is used to build an initial ramdisk. An initial ramdisk is a very small +set of files that are loaded into RAM and "mounted" (as initramfs doesn't +actually use a filesystem) as the kernel boots (before the main root +filesystem is mounted). The usual reason to use an initrd is to load kernel +kernel modules in order to access the root partition. An initrd might also +be required to unlock an encrypted device. Usually these modules are +required to support the filesystem used by the root partition (e.g., ext4, +jfs, xfs), or perhaps the controller that the hard drive is attached to +(SCSI, RAID, etc). Essentially, there are so many different options +available in modern Linux kernels that it isn't practical to try to ship +many different kernels to try to cover everyone's needs. It's a lot more +flexible to ship a generic kernel and a set of kernel modules for it. +.SH OPTIONS +.TP +.B \-F +Use the contents of /etc/mkinitrd.conf as options to mkinitrd (optional). +If this is used in conjunction with any other options passed on the command +line, the command-line options will override the config file options. +.br +See mkinitrd.conf(5) for details. +.TP +.B \-c +Clear the existing initrd tree (by default in /boot/initrd-tree/) first. +If this is not done, running mkinitrd will add additional modules to the +existing initrd. +.TP +.B \-f filesystem +Specify the filesystem to use for the root partition. If this isn't given, +mount will usually figure it out. This option must be used together with the +\-r option in order to be beneficial. +.TP +.B \--help +Display a help summary. +.TP +.B \-h hibernate_partition +Specify the swap partition holding the hibernation image. +.TP +.B \-k kernel version +Use kernel modules from the specified kernel version. mkinitrd will look +for them in /lib/modules/(kernel version). +.TP +.B \-l keymap +Load an alternative keyboard mapping. All supported keyboard mappings +can be found in /usr/share/mkinitrd/keymaps.tar.gz +Leave the '.bmap' out when you supply this parameter. E.g. '-l nl' will +add support for dutch keyboard mapping to the initrd. +.TP +.B \-m module list +This is a list of colon-delimited modules to build into the initrd. +Any dependencies of requested modules will also be added to the initrd. +Additional options may be added to use when loading the kernel modules +(but in this case the entire list must be wrapped with double quotes). +.TP +.B \-o output image +The file to write the initrd to. (default: /boot/initrd.gz) +.TP +.BI \-r \ root_device +Specify the device to be used as the root partition. If this isn't given, the +kernel default will be used (which is usually fine). This option must be used +together with the \-f option in order to be beneficial. +.I root_device +can be a device node path, UUID, or LABEL. See examples for \fB\-C\fR below. +.TP +.B \-s source tree +The directory to use as the source for the initrd. (default: /boot/initrd-tree/) +.TP +.B \-u +Include udev in the initrd. +.TP +.B \-w +The -w option specifies how long to wait in seconds before assuming that all the +drives are spun up and ready to go. +.TP +.BI \-C \ device_list +A colon (:) delimited list of luks encrypted block devices to be unlocked by +the initrd using cryptsetup. +.I device_list +may include any of: device node path, UUID, or LABEL. All devices that must be +unlocked in order to access the root filesystem must be specified. For example: + + -C /dev/sda2:/dev/sda3 +.br + -C UUID=ec6dea40-c8d8-4590-850a-a757be60e45a +.br + -C LABEL=darkstar + +Each unlocked device will be assigned an automatically generated luks device +name of the form luks<device> where '<device>' will be the basename of the +encrypted device node path. For example: + + /dev/mapper/lukssda2 + +As a convenience to users, where -r specifies one of the device names listed +on the -C option it will be automatically adjusted to use the correct luks +device name. i.e. + + "-C /dev/sda2 -r /dev/sda2" and + "-C /dev/sda2 -r /dev/mapper/lukssda2" + +are equivalent. +.br +(Use with '-r' option). +.TP +.B \-K luks_keyfile +When using cryptsetup to encrypt your partition, you can use a keyfile instead +of a passphrase to unlock the LUKS volume. The LUKSKEY variable holds the +filename of a keyfile, as well as the label (or uuid) of the partition this +file is on. This way, you can unlock your computer automatically if you have a +USB stick with your LUKS key inserted at boot. A passphrase will still be asked +if the LUKS key can not be found. +.br +For example, if your USB thumb drive has a FAT partition with label +"TRAVELSTICK" and the actual keyfile is called "/keys/alien.luks", then +you need to set: + + -K LABEL=TRAVELSTICK:/keys/alien.luks +.TP +.B \-T device list +A colon (:) delimited list of luks encrypted block devices to be passed the +"--allow-discards" option when unlocked by the initrd using cryptsetup, e.g. + + -T /dev/sda2:/dev/sda4 + +This has the effect of allowing TRIM on SSD drives. Be sure your SSD supports +this feature (correctly) before enabling it. See fstrim(8) for more information. +.TP +.B \-P microcode_archive +This option specifies a cpio archive containing updated microcode for your CPU. +CPU manufacturers occasionally release such updates to fix bugs in the microcode +currently embedded in the CPU. The microcode archive will be prepended to the +output initrd, where the kernel will find it for early patching: + + -P /boot/intel-ucode.cpio + +.TP +.B \-B +This option adds the btrfs utility to the initrd so that multi-device filesystems +will be picked up by a scan (/sbin/btrfs device scan). This is needed if the +root filesystem is a Btrfs multi-device filesystem. +.TP +.B \-L +This option adds LVM support to the initrd, if the tools are +available on the system. +.TP +.B \-R +This option adds RAID support to the initrd, if a static mdadm binary is +available on the system. +.TP +.B \-V +Display version information and exit. +.SH EXAMPLES +A simple example: Build an initrd for a reiserfs root partition: + + mkinitrd -c -m reiserfs + +Another example: Build an initrd image using Linux 2.6.33.1 kernel +modules for a system with an ext3 root partition on /dev/sdb3: + + mkinitrd -c -k 2.6.33.1 -m ext3 -f ext3 -r /dev/sdb3 + +An example of a single encrypted partition setup: +.br +As a user convenience, the value for the "-r" option may also be specified as +"/dev/sda2" in this example: + + mkinitrd -c -k 2.6.33.1 \\ + -m ext4:ehci-hcd:uhci-hcd:usbhid \\ + -f ext4 -r /dev/mapper/lukssda2 \\ + -C /dev/sda2 \\ + -l uk + +Finally, A more complex example: +.br +This one is for a LVM Volume Group (rootvg) comprising of two LVM Physical +Volumes, each of which is on a LUKS encrypted partition that will need to be +unlocked before the root filesystem (/dev/rootvg/lvroot) can be accessed. + + mkinitrd -c -k 2.6.29.6 \\ + -m ext4:ehci-hcd:uhci-hcd:usbhid \\ + -f ext4 -r /dev/rootvg/lvroot \\ + -L -C /dev/sda2:/dev/sdb2 \\ + -l uk + +If run without options, mkinitrd will rebuild an initrd image using +the contents of the $SOURCE_TREE directory, or, if that directory +does not exist it will be created and populated, and then mkinitrd +will exit. These options are handy for building an initrd mostly +by hand. After creating /boot/initrd-tree/, you can add modules and +edit files by hand, and then rerun mkinitrd to create the initrd. + +Once the initrd is created, you'll need to tell your boot loader +to load it. If you boot with LILO, you will need to add an initrd +line to /etc/lilo.conf. Here's a section of lilo.conf that shows +how to set this up: + + # Linux bootable partition config begins + image = /boot/vmlinuz-generic-2.6.33.1 + initrd = /boot/initrd.gz + root = /dev/sda3 + label = Linux26331 + read-only + # Linux bootable partition config ends + +Note that the line "root = /dev/sda3" is not needed if the root device +has been configured in the initrd image. + +Once you've created the initrd and editing /etc/lilo.conf, you will +need to run 'lilo' to write out the changed boot block. The next +time you reboot the initrd should be loaded along with the kernel. + +Have fun! + +.SH SEE ALSO +mkinitrd.conf (5) + +.SH AUTHOR +Patrick J. Volkerding <volkerdi@slackware.com> |