From 8c5031d63e2132284ddeec9d5143734069c93b2a Mon Sep 17 00:00:00 2001 From: Richard Laager Date: Sat, 11 Dec 2021 19:08:14 -0600 Subject: [PATCH] Revert "Introduce Debian Bullseye root on ZFS howto" This reverts commit b81a4719398f5ac305249bef4f33f96d7a13b7ca. We clashed while working on this. The Bullseye HOWTO in the above commit was not rebased on the current Buster HOWTO, so a lot of its delta between Buster and Bullseye is improper. Signed-off-by: Richard Laager --- .../Debian/Debian Bullseye Root on ZFS.rst | 1119 ----------------- 1 file changed, 1119 deletions(-) delete mode 100644 docs/Getting Started/Debian/Debian Bullseye Root on ZFS.rst diff --git a/docs/Getting Started/Debian/Debian Bullseye Root on ZFS.rst b/docs/Getting Started/Debian/Debian Bullseye Root on ZFS.rst deleted file mode 100644 index edf17aa..0000000 --- a/docs/Getting Started/Debian/Debian Bullseye Root on ZFS.rst +++ /dev/null @@ -1,1119 +0,0 @@ -.. highlight:: sh - -Debian Bullseye Root on ZFS -=========================== - -.. contents:: Table of Contents - :local: - -Overview --------- - -Caution -~~~~~~~ - -- This HOWTO uses a whole physical disk. -- Do not use these instructions for dual-booting. -- Backup your data. Any existing data will be lost. - -System Requirements -~~~~~~~~~~~~~~~~~~~ - -- `64-bit Debian GNU/Linux Bullseye Live CD w/ GUI (e.g. gnome iso) - `__ -- `A 64-bit kernel is strongly encouraged. - `__ -- Installing on a drive which presents 4 KiB logical sectors (a “4Kn” drive) - only works with UEFI booting. This not unique to ZFS. `GRUB does not and - will not work on 4Kn with legacy (BIOS) booting. - `__ - -Computers that have less than 2 GiB of memory run ZFS slowly. 4 GiB of memory -is recommended for normal performance in basic workloads. If you wish to use -deduplication, you will need `massive amounts of RAM -`__. Enabling -deduplication is a permanent change that cannot be easily reverted. - -Support -~~~~~~~ - -If you need help, reach out to the community using the :ref:`mailing_lists` or IRC at -`#zfsonlinux `__ on `Libera Chat -`__. If you have a bug report or feature request -related to this HOWTO, please `file a new issue and mention @rlaager -`__. - -Contributing -~~~~~~~~~~~~ - -#. Fork and clone: https://github.com/openzfs/openzfs-docs - -#. Install the tools:: - - sudo apt install python3-pip - - pip3 install -r docs/requirements.txt - - # Add ~/.local/bin to your $PATH, e.g. by adding this to ~/.bashrc: - PATH=$HOME/.local/bin:$PATH - -#. Make your changes. - -#. Test:: - - cd docs - make html - sensible-browser _build/html/index.html - -#. ``git commit --signoff`` to a branch, ``git push``, and create a pull - request. Mention @rlaager. - -Encryption -~~~~~~~~~~ - -This guide supports three different encryption options: unencrypted, ZFS -native encryption, and LUKS. With any option, all ZFS features are fully -available. - -Unencrypted does not encrypt anything, of course. With no encryption -happening, this option naturally has the best performance. - -ZFS native encryption encrypts the data and most metadata in the root -pool. It does not encrypt dataset or snapshot names or properties. The -boot pool is not encrypted at all, but it only contains the bootloader, -kernel, and initrd. (Unless you put a password in ``/etc/fstab``, the -initrd is unlikely to contain sensitive data.) The system cannot boot -without the passphrase being entered at the console. Performance is -good. As the encryption happens in ZFS, even if multiple disks (mirror -or raidz topologies) are used, the data only has to be encrypted once. - -LUKS encrypts almost everything. The only unencrypted data is the bootloader, -kernel, and initrd. The system cannot boot without the passphrase being -entered at the console. Performance is good, but LUKS sits underneath ZFS, so -if multiple disks (mirror or raidz topologies) are used, the data has to be -encrypted once per disk. - -Step 1: Prepare The Install Environment ---------------------------------------- - -#. Boot the Debian GNU/Linux Live CD. If prompted, login with the username - ``user`` and password ``live``. Connect your system to the Internet as - appropriate (e.g. join your WiFi network). Open a terminal. - -#. Setup and update the repositories:: - - sudo vi /etc/apt/sources.list - - .. code-block:: sourceslist - - deb http://deb.debian.org/debian bullseye main contrib - - :: - - sudo apt update - -#. Optional: Install and start the OpenSSH server in the Live CD environment: - - If you have a second system, using SSH to access the target system can be - convenient:: - - sudo apt install --yes openssh-server - - sudo systemctl restart ssh - - **Hint:** You can find your IP address with - ``ip addr show scope global | grep inet``. Then, from your main machine, - connect with ``ssh user@IP``. - -#. Disable automounting: - - If the disk has been used before (with partitions at the same offsets), - previous filesystems (e.g. the ESP) will automount if not disabled:: - - gsettings set org.gnome.desktop.media-handling automount false - -#. Become root:: - - sudo -i - -#. Install ZFS in the Live CD environment:: - - apt install --yes debootstrap gdisk dkms dpkg-dev zfs-dkms - - modprobe zfs - apt install --yes zfsutils-linux - - - We need to get the module built and loaded before installing - zfsutils-linux or `zfs-mount.service will fail to start - `__. - -Step 2: Disk Formatting ------------------------ - -#. Set a variable with the disk name:: - - DISK=/dev/disk/by-id/scsi-SATA_disk1 - - Always use the long ``/dev/disk/by-id/*`` aliases with ZFS. Using the - ``/dev/sd*`` device nodes directly can cause sporadic import failures, - especially on systems that have more than one storage pool. - - **Hints:** - - - ``ls -la /dev/disk/by-id`` will list the aliases. - - Are you doing this in a virtual machine? If your virtual disk is missing - from ``/dev/disk/by-id``, use ``/dev/vda`` if you are using KVM with - virtio; otherwise, read the `troubleshooting <#troubleshooting>`__ - section. - -#. If you are re-using a disk, clear it as necessary: - - If the disk was previously used in an MD array:: - - apt install --yes mdadm - - # See if one or more MD arrays are active: - cat /proc/mdstat - # If so, stop them (replace ``md0`` as required): - mdadm --stop /dev/md0 - - # For an array using the whole disk: - mdadm --zero-superblock --force $DISK - # For an array using a partition: - mdadm --zero-superblock --force ${DISK}-part2 - - Clear the partition table:: - - sgdisk --zap-all $DISK - - If you get a message about the kernel still using the old partition table, - reboot and start over (except that you can skip this step). - - -#. Partition your disk(s): - - Run this if you need legacy (BIOS) booting:: - - sgdisk -a1 -n1:24K:+1000K -t1:EF02 $DISK - - Run this for UEFI booting (for use now or in the future):: - - sgdisk -n2:1M:+512M -t2:EF00 $DISK - - Run this for the boot pool:: - - sgdisk -n3:0:+1G -t3:BF01 $DISK - - Choose one of the following options: - - - Unencrypted or ZFS native encryption:: - - sgdisk -n4:0:0 -t4:BF00 $DISK - - - LUKS:: - - sgdisk -n4:0:0 -t4:8309 $DISK - - If you are creating a mirror or raidz topology, repeat the partitioning - commands for all the disks which will be part of the pool. - -#. Create the boot pool:: - - zpool create \ - -o cachefile=/etc/zfs/zpool.cache \ - -o ashift=12 -d \ - -o feature@async_destroy=enabled \ - -o feature@bookmarks=enabled \ - -o feature@embedded_data=enabled \ - -o feature@empty_bpobj=enabled \ - -o feature@enabled_txg=enabled \ - -o feature@extensible_dataset=enabled \ - -o feature@filesystem_limits=enabled \ - -o feature@hole_birth=enabled \ - -o feature@large_blocks=enabled \ - -o feature@lz4_compress=enabled \ - -o feature@spacemap_histogram=enabled \ - -o feature@zpool_checkpoint=enabled \ - -O acltype=posixacl -O canmount=off -O compression=lz4 \ - -O devices=off -O normalization=formD -O relatime=on -O xattr=sa \ - -O mountpoint=/boot -R /mnt \ - bpool ${DISK}-part3 - - You should not need to customize any of the options for the boot pool. - - GRUB does not support all of the zpool features. See ``spa_feature_names`` - in `grub-core/fs/zfs/zfs.c - `__. - This step creates a separate boot pool for ``/boot`` with the features - limited to only those that GRUB supports, allowing the root pool to use - any/all features. Note that GRUB opens the pool read-only, so all - read-only compatible features are “supported” by GRUB. - - **Hints:** - - - If you are creating a mirror topology, create the pool using:: - - zpool create \ - ... \ - bpool mirror \ - /dev/disk/by-id/scsi-SATA_disk1-part3 \ - /dev/disk/by-id/scsi-SATA_disk2-part3 - - - For raidz topologies, replace ``mirror`` in the above command with - ``raidz``, ``raidz2``, or ``raidz3`` and list the partitions from - additional disks. - - The pool name is arbitrary. If changed, the new name must be used - consistently. The ``bpool`` convention originated in this HOWTO. - - **Feature Notes:** - - - The ``allocation_classes`` feature should be safe to use. However, unless - one is using it (i.e. a ``special`` vdev), there is no point to enabling - it. It is extremely unlikely that someone would use this feature for a - boot pool. If one cares about speeding up the boot pool, it would make - more sense to put the whole pool on the faster disk rather than using it - as a ``special`` vdev. - - The ``project_quota`` feature has been tested and is safe to use. This - feature is extremely unlikely to matter for the boot pool. - - The ``resilver_defer`` should be safe but the boot pool is small enough - that it is unlikely to be necessary. - - The ``spacemap_v2`` feature has been tested and is safe to use. The boot - pool is small, so this does not matter in practice. - - As a read-only compatible feature, the ``userobj_accounting`` feature - should be compatible in theory, but in practice, GRUB can fail with an - “invalid dnode type” error. This feature does not matter for ``/boot`` - anyway. - -#. Create the root pool: - - Choose one of the following options: - - - Unencrypted:: - - zpool create \ - -o ashift=12 \ - -O acltype=posixacl -O canmount=off -O compression=lz4 \ - -O dnodesize=auto -O normalization=formD -O relatime=on \ - -O xattr=sa -O mountpoint=/ -R /mnt \ - rpool ${DISK}-part4 - - - ZFS native encryption:: - - zpool create \ - -o ashift=12 \ - -O encryption=aes-256-gcm \ - -O keylocation=prompt -O keyformat=passphrase \ - -O acltype=posixacl -O canmount=off -O compression=lz4 \ - -O dnodesize=auto -O normalization=formD -O relatime=on \ - -O xattr=sa -O mountpoint=/ -R /mnt \ - rpool ${DISK}-part4 - - - LUKS:: - - apt install --yes cryptsetup - - cryptsetup luksFormat -c aes-xts-plain64 -s 512 -h sha256 ${DISK}-part4 - cryptsetup luksOpen ${DISK}-part4 luks1 - zpool create \ - -o ashift=12 \ - -O acltype=posixacl -O canmount=off -O compression=lz4 \ - -O dnodesize=auto -O normalization=formD -O relatime=on \ - -O xattr=sa -O mountpoint=/ -R /mnt \ - rpool /dev/mapper/luks1 - - **Notes:** - - - The use of ``ashift=12`` is recommended here because many drives - today have 4 KiB (or larger) physical sectors, even though they - present 512 B logical sectors. Also, a future replacement drive may - have 4 KiB physical sectors (in which case ``ashift=12`` is desirable) - or 4 KiB logical sectors (in which case ``ashift=12`` is required). - - Setting ``-O acltype=posixacl`` enables POSIX ACLs globally. If you - do not want this, remove that option, but later add - ``-o acltype=posixacl`` (note: lowercase “o”) to the ``zfs create`` - for ``/var/log``, as `journald requires ACLs - `__ - - Setting ``normalization=formD`` eliminates some corner cases relating - to UTF-8 filename normalization. It also implies ``utf8only=on``, - which means that only UTF-8 filenames are allowed. If you care to - support non-UTF-8 filenames, do not use this option. For a discussion - of why requiring UTF-8 filenames may be a bad idea, see `The problems - with enforced UTF-8 only filenames - `__. - - ``recordsize`` is unset (leaving it at the default of 128 KiB). If you - want to tune it (e.g. ``-o recordsize=1M``), see `these - `__ `various - `__ `blog - `__ - `posts - `__. - - Setting ``relatime=on`` is a middle ground between classic POSIX - ``atime`` behavior (with its significant performance impact) and - ``atime=off`` (which provides the best performance by completely - disabling atime updates). Since Linux 2.6.30, ``relatime`` has been - the default for other filesystems. See `RedHat’s documentation - `__ - for further information. - - Setting ``xattr=sa`` `vastly improves the performance of extended - attributes - `__. - Inside ZFS, extended attributes are used to implement POSIX ACLs. - Extended attributes can also be used by user-space applications. - `They are used by some desktop GUI applications. - `__ - `They can be used by Samba to store Windows ACLs and DOS attributes; - they are required for a Samba Active Directory domain controller. - `__ - Note that ``xattr=sa`` is `Linux-specific - `__. If you move your - ``xattr=sa`` pool to another OpenZFS implementation besides ZFS-on-Linux, - extended attributes will not be readable (though your data will be). If - portability of extended attributes is important to you, omit the - ``-O xattr=sa`` above. Even if you do not want ``xattr=sa`` for the whole - pool, it is probably fine to use it for ``/var/log``. - - Make sure to include the ``-part4`` portion of the drive path. If you - forget that, you are specifying the whole disk, which ZFS will then - re-partition, and you will lose the bootloader partition(s). - - ZFS native encryption `now - `__ - defaults to ``aes-256-gcm``. - - For LUKS, the key size chosen is 512 bits. However, XTS mode requires two - keys, so the LUKS key is split in half. Thus, ``-s 512`` means AES-256. - - Your passphrase will likely be the weakest link. Choose wisely. See - `section 5 of the cryptsetup FAQ - `__ - for guidance. - - **Hints:** - - - If you are creating a mirror topology, create the pool using:: - - zpool create \ - ... \ - rpool mirror \ - /dev/disk/by-id/scsi-SATA_disk1-part4 \ - /dev/disk/by-id/scsi-SATA_disk2-part4 - - - For raidz topologies, replace ``mirror`` in the above command with - ``raidz``, ``raidz2``, or ``raidz3`` and list the partitions from - additional disks. - - When using LUKS with mirror or raidz topologies, use - ``/dev/mapper/luks1``, ``/dev/mapper/luks2``, etc., which you will have - to create using ``cryptsetup``. - - The pool name is arbitrary. If changed, the new name must be used - consistently. On systems that can automatically install to ZFS, the root - pool is named ``rpool`` by default. - -Step 3: System Installation ---------------------------- - -#. Create filesystem datasets to act as containers:: - - zfs create -o canmount=off -o mountpoint=none rpool/ROOT - zfs create -o canmount=off -o mountpoint=none bpool/BOOT - - On Solaris systems, the root filesystem is cloned and the suffix is - incremented for major system changes through ``pkg image-update`` or - ``beadm``. Similar functionality has been implemented in Ubuntu 20.04 with - the ``zsys`` tool, though its dataset layout is more complicated. Even - without such a tool, the `rpool/ROOT` and `bpool/BOOT` containers can still - be used for manually created clones. That said, this HOWTO assumes a single - filesystem for ``/boot`` for simplicity. - -#. Create filesystem datasets for the root and boot filesystems:: - - zfs create -o canmount=noauto -o mountpoint=/ rpool/ROOT/debian - zfs mount rpool/ROOT/debian - - zfs create -o mountpoint=/boot bpool/BOOT/debian - - With ZFS, it is not normally necessary to use a mount command (either - ``mount`` or ``zfs mount``). This situation is an exception because of - ``canmount=noauto``. - -#. Create datasets:: - - zfs create rpool/home - zfs create -o mountpoint=/root rpool/home/root - chmod 700 /mnt/root - zfs create -o canmount=off rpool/var - zfs create -o canmount=off rpool/var/lib - zfs create rpool/var/log - zfs create rpool/var/spool - - The datasets below are optional, depending on your preferences and/or - software choices. - - If you wish to exclude these from snapshots:: - - zfs create -o com.sun:auto-snapshot=false rpool/var/cache - zfs create -o com.sun:auto-snapshot=false rpool/var/tmp - chmod 1777 /mnt/var/tmp - - If you use /opt on this system:: - - zfs create rpool/opt - - If you use /srv on this system:: - - zfs create rpool/srv - - If you use /usr/local on this system:: - - zfs create -o canmount=off rpool/usr - zfs create rpool/usr/local - - If this system will have games installed:: - - zfs create rpool/var/games - - If this system will store local email in /var/mail:: - - zfs create rpool/var/mail - - If this system will use Snap packages:: - - zfs create rpool/var/snap - - If you use /var/www on this system:: - - zfs create rpool/var/www - - If this system will use GNOME:: - - zfs create rpool/var/lib/AccountsService - - If this system will use Docker (which manages its own datasets & - snapshots):: - - zfs create -o com.sun:auto-snapshot=false rpool/var/lib/docker - - If this system will use NFS (locking):: - - zfs create -o com.sun:auto-snapshot=false rpool/var/lib/nfs - - Mount a tmpfs at /run:: - - mkdir /mnt/run - mount -t tmpfs tmpfs /mnt/run - mkdir /mnt/run/lock - - A tmpfs is recommended later, but if you want a separate dataset for - ``/tmp``:: - - zfs create -o com.sun:auto-snapshot=false rpool/tmp - chmod 1777 /mnt/tmp - - The primary goal of this dataset layout is to separate the OS from user - data. This allows the root filesystem to be rolled back without rolling - back user data. - - If you do nothing extra, ``/tmp`` will be stored as part of the root - filesystem. Alternatively, you can create a separate dataset for ``/tmp``, - as shown above. This keeps the ``/tmp`` data out of snapshots of your root - filesystem. It also allows you to set a quota on ``rpool/tmp``, if you want - to limit the maximum space used. Otherwise, you can use a tmpfs (RAM - filesystem) later. - -#. Install the minimal system:: - - debootstrap --components=main,contrib bullseye /mnt - - The ``debootstrap`` command leaves the new system in an unconfigured state. - An alternative to using ``debootstrap`` is to copy the entirety of a - working system into the new ZFS root. - -#. Copy in zpool.cache:: - - mkdir /mnt/etc/zfs - cp /etc/zfs/zpool.cache /mnt/etc/zfs/ - -Step 4: System Configuration ----------------------------- - -#. Configure the hostname: - - Replace ``HOSTNAME`` with the desired hostname:: - - echo HOSTNAME > /mnt/etc/hostname - vi /mnt/etc/hosts - - .. code-block:: text - - Add a line: - 127.0.1.1 HOSTNAME - or if the system has a real name in DNS: - 127.0.1.1 FQDN HOSTNAME - - **Hint:** Use ``nano`` if you find ``vi`` confusing. - -#. Configure the network interface: - - Find the interface name:: - - ip addr show - - Adjust ``NAME`` below to match your interface name:: - - vi /mnt/etc/network/interfaces.d/NAME - - .. code-block:: text - - auto NAME - iface NAME inet dhcp - - Customize this file if the system is not a DHCP client. - -#. Configure the package sources:: - - vi /mnt/etc/apt/sources.list - - .. code-block:: sourceslist - - deb http://deb.debian.org/debian bullseye main contrib - deb http://security.debian.org/debian-security bullseye-security/updates main contrib - deb http://deb.debian.org/debian bullseye-updates main contrib - - :: - - -#. Bind the virtual filesystems from the LiveCD environment to the new - system and ``chroot`` into it:: - - mount --rbind /dev /mnt/dev - mount --rbind /proc /mnt/proc - mount --rbind /sys /mnt/sys - mount -t tmpfs tmpfs /mnt/run - mkdir /mnt/run/lock - chroot /mnt /usr/bin/env DISK=$DISK bash --login - - **Note:** This is using ``--rbind``, not ``--bind``. - -#. Configure a basic system environment:: - - ln -s /proc/self/mounts /etc/mtab - apt update - - apt install --yes console-setup locales - - Even if you prefer a non-English system language, always ensure that - ``en_US.UTF-8`` is available:: - - dpkg-reconfigure locales tzdata keyboard-configuration console-setup - -#. Install ZFS in the chroot environment for the new system:: - - apt install --yes dpkg-dev linux-headers-amd64 linux-image-amd64 - - apt install --yes zfs-initramfs - - echo REMAKE_INITRD=yes > /etc/dkms/zfs.conf - -#. For LUKS installs only, setup ``/etc/crypttab``:: - - apt install --yes cryptsetup - - echo luks1 /dev/disk/by-uuid/$(blkid -s UUID -o value ${DISK}-part4) \ - none luks,discard,initramfs > /etc/crypttab - - The use of ``initramfs`` is a work-around for `cryptsetup does not support - ZFS `__. - - **Hint:** If you are creating a mirror or raidz topology, repeat the - ``/etc/crypttab`` entries for ``luks2``, etc. adjusting for each disk. - -#. Install GRUB - - Choose one of the following options: - - - Install GRUB for legacy (BIOS) booting:: - - apt install --yes grub-pc - - Select (using the space bar) all of the disks (not partitions) in your - pool. - - - Install GRUB for UEFI booting:: - - apt install dosfstools - - mkdosfs -F 32 -s 1 -n EFI ${DISK}-part2 - mkdir /boot/efi - echo /dev/disk/by-uuid/$(blkid -s UUID -o value ${DISK}-part2) \ - /boot/efi vfat defaults 0 0 >> /etc/fstab - mount /boot/efi - apt install --yes grub-efi-amd64 shim-signed - - **Notes:** - - - The ``-s 1`` for ``mkdosfs`` is only necessary for drives which present - 4 KiB logical sectors (“4Kn” drives) to meet the minimum cluster size - (given the partition size of 512 MiB) for FAT32. It also works fine on - drives which present 512 B sectors. - - For a mirror or raidz topology, this step only installs GRUB on the - first disk. The other disk(s) will be handled later. - -#. Optional: Remove os-prober:: - - apt remove --purge os-prober - - This avoids error messages from `update-grub`. `os-prober` is only - necessary in dual-boot configurations. - -#. Set a root password:: - - passwd - -#. Enable importing bpool - - This ensures that ``bpool`` is always imported, regardless of whether - ``/etc/zfs/zpool.cache`` exists, whether it is in the cachefile or not, - or whether ``zfs-import-scan.service`` is enabled. - - :: - - vi /etc/systemd/system/zfs-import-bpool.service - - .. code-block:: ini - - [Unit] - DefaultDependencies=no - Before=zfs-import-scan.service - Before=zfs-import-cache.service - - [Service] - Type=oneshot - RemainAfterExit=yes - ExecStart=/sbin/zpool import -N -o cachefile=none bpool - # Work-around to preserve zpool cache: - ExecStartPre=-/bin/mv /etc/zfs/zpool.cache /etc/zfs/preboot_zpool.cache - ExecStartPost=-/bin/mv /etc/zfs/preboot_zpool.cache /etc/zfs/zpool.cache - - [Install] - WantedBy=zfs-import.target - - :: - - systemctl enable zfs-import-bpool.service - -#. Optional (but recommended): Mount a tmpfs to ``/tmp`` - - If you chose to create a ``/tmp`` dataset above, skip this step, as they - are mutually exclusive choices. Otherwise, you can put ``/tmp`` on a - tmpfs (RAM filesystem) by enabling the ``tmp.mount`` unit. - - :: - - cp /usr/share/systemd/tmp.mount /etc/systemd/system/ - systemctl enable tmp.mount - -#. Optional (but kindly requested): Install popcon - - The ``popularity-contest`` package reports the list of packages install - on your system. Showing that ZFS is popular may be helpful in terms of - long-term attention from the distro. - - :: - - apt install --yes popularity-contest - - Choose Yes at the prompt. - -Step 5: GRUB Installation -------------------------- - -#. Verify that the ZFS boot filesystem is recognized:: - - grub-probe /boot - -#. Refresh the initrd files:: - - update-initramfs -c -k all - - **Note:** When using LUKS, this will print “WARNING could not determine - root device from /etc/fstab”. This is because `cryptsetup does not - support ZFS - `__. - -#. Workaround GRUB's missing zpool-features support:: - - vi /etc/default/grub - # Set: GRUB_CMDLINE_LINUX="root=ZFS=rpool/ROOT/debian" - -#. Optional (but highly recommended): Make debugging GRUB easier:: - - vi /etc/default/grub - # Remove quiet from: GRUB_CMDLINE_LINUX_DEFAULT - # Uncomment: GRUB_TERMINAL=console - # Save and quit. - - Later, once the system has rebooted twice and you are sure everything is - working, you can undo these changes, if desired. - -#. Update the boot configuration:: - - update-grub - - **Note:** Ignore errors from ``osprober``, if present. - -#. Install the boot loader: - - #. For legacy (BIOS) booting, install GRUB to the MBR:: - - grub-install $DISK - - Note that you are installing GRUB to the whole disk, not a partition. - - If you are creating a mirror or raidz topology, repeat the ``grub-install`` - command for each disk in the pool. - - #. For UEFI booting, install GRUB to the ESP:: - - grub-install --target=x86_64-efi --efi-directory=/boot/efi \ - --bootloader-id=debian --recheck --no-floppy - - It is not necessary to specify the disk here. If you are creating a - mirror or raidz topology, the additional disks will be handled later. - -#. Fix filesystem mount ordering: - - We need to activate ``zfs-mount-generator``. This makes systemd aware of - the separate mountpoints, which is important for things like ``/var/log`` - and ``/var/tmp``. In turn, ``rsyslog.service`` depends on ``var-log.mount`` - by way of ``local-fs.target`` and services using the ``PrivateTmp`` feature - of systemd automatically use ``After=var-tmp.mount``. - - :: - - mkdir /etc/zfs/zfs-list.cache - touch /etc/zfs/zfs-list.cache/bpool - touch /etc/zfs/zfs-list.cache/rpool - ln -s /usr/lib/zfs-linux/zed.d/history_event-zfs-list-cacher.sh /etc/zfs/zed.d - zed -F & - - Verify that ``zed`` updated the cache by making sure these are not empty:: - - cat /etc/zfs/zfs-list.cache/bpool - cat /etc/zfs/zfs-list.cache/rpool - - If either is empty, force a cache update and check again:: - - zfs set canmount=on bpool/BOOT/debian - zfs set canmount=noauto rpool/ROOT/debian - - If they are still empty, stop zed (as below), start zed (as above) and try - again. - - Stop ``zed``:: - - fg - Press Ctrl-C. - - Fix the paths to eliminate ``/mnt``:: - - sed -Ei "s|/mnt/?|/|" /etc/zfs/zfs-list.cache/* - -Step 6: First Boot ------------------- - -#. Optional: Install SSH:: - - apt install --yes openssh-server - - vi /etc/ssh/sshd_config - # Set: PermitRootLogin yes - -#. Optional: Snapshot the initial installation:: - - zfs snapshot bpool/BOOT/debian@install - zfs snapshot rpool/ROOT/debian@install - - In the future, you will likely want to take snapshots before each - upgrade, and remove old snapshots (including this one) at some point to - save space. - -#. Exit from the ``chroot`` environment back to the LiveCD environment:: - - exit - -#. Run these commands in the LiveCD environment to unmount all - filesystems:: - - mount | grep -v zfs | tac | awk '/\/mnt/ {print $3}' | \ - xargs -i{} umount -lf {} - zpool export -a - -#. Reboot:: - - reboot - - Wait for the newly installed system to boot normally. Login as root. - -#. Create a user account: - - Replace ``YOUR_USERNAME`` with your desired username:: - - username=YOUR_USERNAME - - zfs create rpool/home/$username - adduser $username - - cp -a /etc/skel/. /home/$username - chown -R $username:$username /home/$username - usermod -a -G audio,cdrom,dip,floppy,netdev,plugdev,sudo,video $username - -#. Mirror GRUB - - If you installed to multiple disks, install GRUB on the additional - disks. - - - For legacy (BIOS) booting:: - - dpkg-reconfigure grub-pc - - Hit enter until you get to the device selection screen. - Select (using the space bar) all of the disks (not partitions) in your pool. - - - For UEFI booting:: - - umount /boot/efi - - For the second and subsequent disks (increment debian-2 to -3, etc.):: - - dd if=/dev/disk/by-id/scsi-SATA_disk1-part2 \ - of=/dev/disk/by-id/scsi-SATA_disk2-part2 - efibootmgr -c -g -d /dev/disk/by-id/scsi-SATA_disk2 \ - -p 2 -L "debian-2" -l '\EFI\debian\grubx64.efi' - - mount /boot/efi - -Step 7: Optional: Configure Swap ---------------------------------- - -**Caution**: On systems with extremely high memory pressure, using a -zvol for swap can result in lockup, regardless of how much swap is still -available. There is `a bug report upstream -`__. - -#. Create a volume dataset (zvol) for use as a swap device:: - - zfs create -V 4G -b $(getconf PAGESIZE) -o compression=zle \ - -o logbias=throughput -o sync=always \ - -o primarycache=metadata -o secondarycache=none \ - -o com.sun:auto-snapshot=false rpool/swap - - You can adjust the size (the ``4G`` part) to your needs. - - The compression algorithm is set to ``zle`` because it is the cheapest - available algorithm. As this guide recommends ``ashift=12`` (4 kiB - blocks on disk), the common case of a 4 kiB page size means that no - compression algorithm can reduce I/O. The exception is all-zero pages, - which are dropped by ZFS; but some form of compression has to be enabled - to get this behavior. - -#. Configure the swap device: - - **Caution**: Always use long ``/dev/zvol`` aliases in configuration - files. Never use a short ``/dev/zdX`` device name. - - :: - - mkswap -f /dev/zvol/rpool/swap - echo /dev/zvol/rpool/swap none swap discard 0 0 >> /etc/fstab - echo RESUME=none > /etc/initramfs-tools/conf.d/resume - - The ``RESUME=none`` is necessary to disable resuming from hibernation. - This does not work, as the zvol is not present (because the pool has not - yet been imported) at the time the resume script runs. If it is not - disabled, the boot process hangs for 30 seconds waiting for the swap - zvol to appear. - -#. Enable the swap device:: - - swapon -av - -Step 8: Full Software Installation ----------------------------------- - -#. Upgrade the minimal system:: - - apt dist-upgrade --yes - -#. Install a regular set of software:: - - tasksel - -#. Optional: Disable log compression: - - As ``/var/log`` is already compressed by ZFS, logrotate’s compression is - going to burn CPU and disk I/O for (in most cases) very little gain. Also, - if you are making snapshots of ``/var/log``, logrotate’s compression will - actually waste space, as the uncompressed data will live on in the - snapshot. You can edit the files in ``/etc/logrotate.d`` by hand to comment - out ``compress``, or use this loop (copy-and-paste highly recommended):: - - for file in /etc/logrotate.d/* ; do - if grep -Eq "(^|[^#y])compress" "$file" ; then - sed -i -r "s/(^|[^#y])(compress)/\1#\2/" "$file" - fi - done - -#. Reboot:: - - reboot - -Step 9: Final Cleanup ---------------------- - -#. Wait for the system to boot normally. Login using the account you - created. Ensure the system (including networking) works normally. - -#. Optional: Delete the snapshots of the initial installation:: - - sudo zfs destroy bpool/BOOT/debian@install - sudo zfs destroy rpool/ROOT/debian@install - -#. Optional: Disable the root password:: - - sudo usermod -p '*' root - -#. Optional (but highly recommended): Disable root SSH logins: - - If you installed SSH earlier, revert the temporary change:: - - sudo vi /etc/ssh/sshd_config - # Remove: PermitRootLogin yes - - sudo systemctl restart ssh - -#. Optional: Re-enable the graphical boot process: - - If you prefer the graphical boot process, you can re-enable it now. If - you are using LUKS, it makes the prompt look nicer. - - :: - - sudo vi /etc/default/grub - # Add quiet to GRUB_CMDLINE_LINUX_DEFAULT - # Comment out GRUB_TERMINAL=console - # Save and quit. - - sudo update-grub - - **Note:** Ignore errors from ``osprober``, if present. - -#. Optional: For LUKS installs only, backup the LUKS header:: - - sudo cryptsetup luksHeaderBackup /dev/disk/by-id/scsi-SATA_disk1-part4 \ - --header-backup-file luks1-header.dat - - Store that backup somewhere safe (e.g. cloud storage). It is protected by - your LUKS passphrase, but you may wish to use additional encryption. - - **Hint:** If you created a mirror or raidz topology, repeat this for each - LUKS volume (``luks2``, etc.). - -Troubleshooting ---------------- - -Rescuing using a Live CD -~~~~~~~~~~~~~~~~~~~~~~~~ - -Go through `Step 1: Prepare The Install Environment -<#step-1-prepare-the-install-environment>`__. - -For LUKS, first unlock the disk(s):: - - apt install --yes cryptsetup - - cryptsetup luksOpen /dev/disk/by-id/scsi-SATA_disk1-part4 luks1 - # Repeat for additional disks, if this is a mirror or raidz topology. - -Mount everything correctly:: - - zpool export -a - zpool import -N -R /mnt rpool - zpool import -N -R /mnt bpool - zfs load-key -a - zfs mount rpool/ROOT/debian - zfs mount -a - -If needed, you can chroot into your installed environment:: - - mount --rbind /dev /mnt/dev - mount --rbind /proc /mnt/proc - mount --rbind /sys /mnt/sys - chroot /mnt /bin/bash --login - mount /boot - mount -a - -Do whatever you need to do to fix your system. - -When done, cleanup:: - - exit - mount | grep -v zfs | tac | awk '/\/mnt/ {print $3}' | \ - xargs -i{} umount -lf {} - zpool export -a - reboot - -Areca -~~~~~ - -Systems that require the ``arcsas`` blob driver should add it to the -``/etc/initramfs-tools/modules`` file and run ``update-initramfs -c -k all``. - -Upgrade or downgrade the Areca driver if something like -``RIP: 0010:[] [] native_read_tsc+0x6/0x20`` -appears anywhere in kernel log. ZoL is unstable on systems that emit this -error message. - -MPT2SAS -~~~~~~~ - -Most problem reports for this tutorial involve ``mpt2sas`` hardware that does -slow asynchronous drive initialization, like some IBM M1015 or OEM-branded -cards that have been flashed to the reference LSI firmware. - -The basic problem is that disks on these controllers are not visible to the -Linux kernel until after the regular system is started, and ZoL does not -hotplug pool members. See `https://github.com/zfsonlinux/zfs/issues/330 -`__. - -Most LSI cards are perfectly compatible with ZoL. If your card has this -glitch, try setting ``ZFS_INITRD_PRE_MOUNTROOT_SLEEP=X`` in -``/etc/default/zfs``. The system will wait ``X`` seconds for all drives to -appear before importing the pool. - -QEMU/KVM/XEN -~~~~~~~~~~~~ - -Set a unique serial number on each virtual disk using libvirt or qemu -(e.g. ``-drive if=none,id=disk1,file=disk1.qcow2,serial=1234567890``). - -To be able to use UEFI in guests (instead of only BIOS booting), run -this on the host:: - - sudo apt install ovmf - sudo vi /etc/libvirt/qemu.conf - -Uncomment these lines: - -.. code-block:: text - - nvram = [ - "/usr/share/OVMF/OVMF_CODE.fd:/usr/share/OVMF/OVMF_VARS.fd", - "/usr/share/OVMF/OVMF_CODE.secboot.fd:/usr/share/OVMF/OVMF_VARS.fd", - "/usr/share/AAVMF/AAVMF_CODE.fd:/usr/share/AAVMF/AAVMF_VARS.fd", - "/usr/share/AAVMF/AAVMF32_CODE.fd:/usr/share/AAVMF/AAVMF32_VARS.fd" - ] - -:: - - sudo systemctl restart libvirtd.service - -VMware -~~~~~~ - -- Set ``disk.EnableUUID = "TRUE"`` in the vmx file or vsphere configuration. - Doing this ensures that ``/dev/disk`` aliases are created in the guest.