Instal linux from linux

Install Arch Linux from existing Linux (Русский)

Эта статья или раздел нуждается в переводе

Этот документ описывает bootstrapping process, нужный для того, чтобы установить Arch Linux из уже работающего хоста Linux. После bootstrapping, установка продолжается так, как описано в руководстве по установке Arch Linux.

Установка Arch Linux из-под другого Linux полезна для:

• беспроводной установки Arch Linux, например для виртуального сервера
• замены существующего Linux без LiveCD (смотрите #Замена уже существующей системы без LiveCD)
• создания нового дистрибутива Linux или LiveCD основанного на Arch Linux
• создания chroot окружения Arch Linux, например для контейнеров Docker
• rootfs-over-NFS для бездисковых систем

Цель процедуры начальной загрузки в том, чтобы настроить окружение, из которого можно будет запустить arch-install-scripts (содержит такие скрипты как pacstrap и arch-root ). Установить arch-install-scripts нужно на самой хост-системе или настройкой chroot основанного на Arch Linux.

Если хост работает под Arch Linux, сразу установите arch-install-scripts .

Contents

Arch Linux-based chroot

Идея состоит в том, чтобы как бы запустить Arch Linux внутри уже имеющейся системы. Настоящая установка, которая будет содержаться внутри chroot, будет затем запущена из этой Arch системы. Есть два способа настроить и войти в chroot, они представлены ниже.

Создаём chroot

Способ 1: Использование Bootstrap образа (рекомендуется)

Скачиваем образ bootstrap с любого желаемого зеркала, либо сразу используя прямую ссылку на нужный вам образ (с зеркала kernel.org):
Образ x86_64:

Внимание! Ссылки могут оказаться нерабочими. В этом случае перейдите по адресу https://mirrors.kernel.org/archlinux/iso/ и найдите образ там

Выбираем подходящий для вашего интернета сервер, откуда будут загружаться основные репозитории:

Войдём в chroot

• Если установлен bash 4 или новее, то:

• Иначе:

Способ 2: Используя образ LiveCD

Можно смонтировать корневой образ последнего установочного диска Arch Linux и затем заchroot’ить туда. Плюс этого способа в том, что у вас будет сразу рабочий Arch Linux installation прямо внутри хост-системы без надобности в его настройки.

• Корневой образ можно скачать с одного из зеркал в папке arch/x86_64/ либо arch/i686/, смотря какую архитектуру хотите. Образ имеет формат squashfs, который является read-only, поэтому нам надо распаковать его и смонтировать корневой образ (root-image.fs).

• Чтобы распаковать корневой образ, надо

• Теперь смонтируем его с помощью опции loop

• Перед тем как chrooting to it, нужно смонтировать некоторые виртуальные системные разделы, а затем скопировать resolv.conf для интернета.

• Теперь всё готово, чтобы to chroot в только что установленное окружение Arch

Используем наше chroot окружение

Начальная настройка хранилища ключей pacman

Перед установкой, ключи pacman должны быть настроены. Перед тем как вводить следующие две команды, можете почитать pacman/Подпись пакета#Инициализация связки ключей, чтобы узнать entropy requirements:

Установка

Хост Debian

На хостах Debian pacstrap выводит следующую ошибку:

Это потому, что в Debian /dev/shm ссылается на /run/shm , который в Arch-based chroot не существует, поэтому ссылка не рабочая. Чтобы исправить это, просто создайте каталог /run/shm :

Хост Fedora

На хостах Fedora и Live USB, если у вас не получается сгенерировать ваш fstab с помощью genfstab , то удалите из fstab одинаковые записи и везде опции seclabel (это опция специфична для Fedora и поэтому не даст вам загрузиться).

Настройка системы

С этого момента просто следуйте согласно разделам начиная с «Монтирование разделов» из руководства по установке Arch Linux.

Замена уже существующей системы без LiveCD

650МБ, например, переформатировав существующий swap-раздел (после окончания установки, можете обратно создать swap). Если не можете столько освободить, выясните точно, какие пакеты группы base вам понадобятся для того, чтобы get a system с работающим интернетом and running in the temporary partition. То есть надо будет ясно указать каждый пакет для pacstrap. И ещё надо указать -c, чтобы пакеты скачивались на хост-систему, дабы избежать недостатка свободного места.

После того как установили, перезагрузитесь в свою новую систему, затем rsync the entire system to the primary partition. Fix the bootloader configuration before rebooting.

Источник

Install Arch Linux from existing Linux

This document describes the bootstrapping process required to install Arch Linux from a running Linux host system. After bootstrapping, the installation proceeds as described in the Installation guide.

Installing Arch Linux from a running Linux is useful for:

• remotely installing Arch Linux, e.g. a (virtual) root server
• replacing an existing Linux without a LiveCD (see #Replacing the existing system without a LiveCD)
• creating a new Linux distribution or LiveMedia based on Arch Linux
• creating an Arch Linux chroot environment, e.g. for a Docker base container
• rootfs-over-NFS for diskless machines

The goal of the bootstrapping procedure is to setup an environment from which the scripts from arch-install-scripts (such as pacstrap and arch-chroot ) can be run.

If the host system runs Arch Linux, this can be achieved by simply installing arch-install-scripts . If the host system runs another Linux distribution, you will first need to set up an Arch Linux-based chroot.

Contents

Backup and preparation

Backup all your data including mails, webservers, etc. Have all information at your fingertips. Preserve all your server configurations, hostnames, etc.

Here is a list of data you will likely need:

• IP address
• hostname(s), (note: rootserver are mostly also part of the providers domain, check or save your /etc/hosts before you delete)
• DNS server (check /etc/resolv.conf )
• SSH keys (if other people work on your server, they will have to accept new keys otherwise. This includes keys from your Apache, your mail servers, your SSH server and others.)
• Hardware info (network card, etc. Refer to your pre-installed /etc/modules.conf )
• Grub configuration files.

In general, it is a good idea to have a local copy of your original /etc directory on your local hard drive.

From a host running Arch Linux

Follow Installation guide#Mount the file systems to mount the filesystem that will be used for the root directory as well as all the other needed mount points. If you already use the /mnt directory for something else, just create another directory such as /mnt/install and use it as the mount point base for the rest of the installation.

At this stage, Arch Linux can either be installed from scratch or it can mirror the host installation. The two options are described thereafter.

Create a new Arch installation

In the procedure, the first step, Installation guide#Select the mirrors, can be skipped since the host should already have a correct mirrorlist.

Create a copy of an existing Arch installation

It is possible to replicate an existing Arch Linux installation by copying the host filesystem to the new partition and make some adjustments to it to make it bootable and unique.

The first step is to copy the host files into the mounted new partition, for this, consider using the approach exhibited in rsync#Full system backup.

Then, follow the procedure described in Installation guide#Configure the system with some caveats and additional steps:

• Installation guide#Time zone, Installation guide#Localization and Installation guide#Root password can be skipped
• Installation guide#Initramfs may be required in particular if changing filesystem, for example from ext4 to Btrfs
• Regarding Installation guide#Boot loader, it is necessary to reinstall the bootloader
• Delete /etc/machine-id so that a new, unique one, is generated at the next boot

If the mirrored Arch installation may be used within a different configuration or with another hardware, consider the following additional operations:

• Use the CPU microcode update adapted to the target system during the step Installation guide#Boot loader
• If any specific Xorg#Configuration was present on the host and may be incompatible with the target system, follow Moving an existing install into (or out of) a virtual machine#Disable any Xorg-related files
• Make any other adjustment appropriate to the target system, like reconfiguring the network or the audio.

From a host running another Linux distribution

There are multiple tools which automate a large part of the steps described in the following subsections. See their respective homepages for detailed instructions.

The manual way is presented in the following subsections. The idea is to either get pacman working directly on the host system, or to run an Arch system inside the host system, with the actual installation being executed from the Arch system. The nested system is contained inside a chroot.

Using pacman from the host system

Pacman can be compiled on most Linux distributions, and used directly on the host system to bootstrap Arch Linux. The arch-install-scripts should run without issues directly from the downloaded sources on any recent distribution.

Some distributions provide a package for pacman and/or arch-install-scripts in their official repositories which can be used for this purpose. As of July 2020, Void Linux is known to provide the pacman package, and Alpine Linux and Fedora are known to provide both pacman and arch-install-scripts.

Creating a chroot

Two methods to setup and enter the chroot are presented below, from the easiest to the most complicated. Select only one of the two methods. Then, continue at #Using a chroot environment.

Method A: Using the bootstrap image (recommended)

Download the bootstrap image from a mirror into /tmp . You can also download the signature (same URL with .sig added) and verify it with GnuPG.

Extract the tarball:

Select a repository server by editing /tmp/root.x86_64/etc/pacman.d/mirrorlist .

Enter the chroot:

• If bash 4 or later is installed, and unshare supports the —fork and —pid options:
• Otherwise, run the following commands:

Method B: Using the LiveCD image

It is possible to mount the root image of the latest Arch Linux installation media and then chroot into it. This method has the advantage of providing a working Arch Linux installation right within the host system without the need to prepare it by installing specific packages.

The root image can be found on one of the mirrors under iso/latest/arch/x86_64/ . The squashfs format is not editable, so we unsquash the root image and mount it.

To unsquash the root image, run

Select a repository server by editing squashfs-root/etc/pacman.d/mirrorlist .

Before chrooting to the unsquashed root image, we need to set up some mount points and copy the resolv.conf for networking.

Now, everything is prepared to chroot into the newly installed Arch environment:

Using a chroot environment

The bootstrap environment is really barebones (no nano or lvm2 ). Therefore, we need to set up pacman in order to download other necessary packages.

Initializing pacman keyring

Before starting the installation, pacman keys need to be setup. Before running the following two commands, read pacman-key#Initializing the keyring to understand the entropy requirements:

If you prefer generating entropy through system activity and decide to run ls -Ra / in another console (TTY, terminal, SSH session. ), do not be afraid of running it in a loop a few times: five or six runs from the host proved sufficient to generate enough entropy on a remote headless server.

Downloading basic tools

Installation tips

Some host systems or configurations may require certain extra steps. See the sections below for tips.

Debian-based host

/dev/shm

On some Debian-based host systems, pacstrap may produce the following error:

This is because in some versions of Debian, /dev/shm points to /run/shm while in the Arch-based chroot, /run/shm does not exist and the link is broken. To correct this error, create a directory /run/shm :

/dev/pts

While installing archlinux-2015.07.01-x86_64 from a Debian 7 host, the following error prevented both pacstrap(8) and arch-chroot from working:

Apparently, this is because these two scripts use a common function. chroot_setup() [1] relies on newer features of util-linux , which are incompatible with Debian 7 userland (see FS#45737).

The solution for pacstrap is to manually execute its various tasks, but use the regular procedure to mount the kernel filesystems on the target directory ( «$newroot» ):

Instead of using arch-chroot for Installation guide#Chroot, simply use:

lvmetad

Trying to create LVM logical volumes from an archlinux-bootstrap-2015.07.01-x86_64 environment on a Debian 7 host resulted in the following error:

(Physical volume and volume group creation worked despite /run/lvm/lvmetad.socket: connect failed: No such file or directory being displayed.)

This could be easily worked around by creating the logical volumes outside the chroot (from the Debian host). They are then available once chrooted again.

The factual accuracy of this article or section is disputed.

Also, if the system you are using has lvm, you might have the following output:

This is because debian does not use lvmetad by default. You need to edit /etc/lvm/lvm.conf and set use_lvmetad to 0 :

The factual accuracy of this article or section is disputed.

This article or section needs language, wiki syntax or style improvements. See Help:Style for reference.

This will trigger later an error on boot in the initrd stage. Therefore, you have to change it back after the grub generation. In a software RAID + LVM, steps would be the following:

• After installing the system, double check your Mkinitcpio and your bootloader settings. See Arch boot process#Boot loader for a list of bootloaders.
• You may need to change your /etc/mdadm.conf to reflect your RAID settings (if applicable).
• You may need to change your HOOKS and MODULES according to your LVM and RAID requirements: MODULES=»dm_mod» HOOKS=»base udev mdadm_udev . block lvm2 filesystems . «
• You will most likely need to generate new initrd images with mkinitcpio. See Mkinitcpio#Image creation and activation.
• Set use_lvmetad = 0 in /etc/lvm/lvm.conf .
• Update your bootloader settings. See your bootloader’s wiki page for details.
• Set use_lvmetad = 1 in /etc/lvm/lvm.conf .

Fedora-based host

On Fedora based hosts and live USBs you may encounter problems when using genfstab to generate your fstab. Remove duplicate entries and the «seclabel» option where it appears, as this is Fedora-specific and will keep your system from booting normally.

Things to check before you reboot

Before rebooting, doublecheck a few details in your installation to achieve a successful installation. To do so, first chroot into the newly-installed system, and then:

• create a user with password, so you can login via ssh. This is critical since root login is disabled by default since OpenSSH-7.1p2.
• set a root password so that you can switch to root via su later
• install a ssh solution and enable its server instance to start automatically at boot.
• set up your network configuration in order to have a connection started automatically at boot.
• set up a boot loader and configure it to use the swap partition you appropriated earlier as the root partition. You might want to configure your bootloader to be able to boot into your old system; it is helpful to re-use the server’s existing /boot partition in the new system for this purpose.

Replacing the existing system without a LiveCD

700 MB of free space somewhere on the disk, e.g. by partitioning a swap partition. You can disable the swap partition and set up your system there.

Set old swap partition as new root partition

Check cfdisk , /proc/swaps or /etc/fstab to find your swap partition. Assuming your hard drive is located on sdaX ( X will be a number).

Do the following:

Disable the swap space:

Create a filesystem on it

Create a directory to mount it in

Finally, mount the new directory for installing the intermediate system.

Installation

Install essentials packages and any other package required to get a system with internet connection up and running in the temporary partition, being careful with the limit of

700 MB space. When specifying packages to be installed with pacstrap, consider adding the -c flag to avoid filling up valuable space by downloading packages to the host system.

Once the new Arch Linux system is installed, fix the bootloader configuration, then reboot into the newly created system, and rsync the entire system to the primary partition.

Источник