A bootable clone is a disk that holds a complete copy of a running system that\u2019s ready to boot. Bootable clones can be a critical part of your backup strategy.<\/p>\n
<\/p>\n
If you already know why you want a bootable clone, just skip to the recipe<\/a>.<\/p>\n If you\u2019re truly hardcore, and just want a command reference so you don\u2019t leave out any steps, skip to the expert mode recipe<\/a>.<\/p>\n If you have mission critical computers in your life, I hope you are already aware of the importance of good backups. I\u2019ve noticed, though, that a lot of people think that just having copies of all their files is enough. They\u2019ll set up, say, an automated cloud backup \u2014 and figure they\u2019re done.<\/p>\n They\u2019re probably in for a nasty surprise if disaster hits.<\/p>\n A lot of the information in your computer isn\u2019t in the files, but in various nebulous kinds of metadata: where the files are located, various configuration files, license keys, special directories, file links, permissions\u2026 Just restoring all your files isn\u2019t enough if you want to be back online as fast as possible.<\/p>\n My primary laptop is a macOS machine. I\u2019ve long employed SuperDuper<\/a> and Carbon Copy Cloner<\/a> to make bootable clones. If my laptop gets destroyed, lost, or stolen, all I have to do is plug a clone into any recent-vintage Macintosh, reboot, and I\u2019m back in production. I don\u2019t even have to wait for files to copy. By contrast, last year I tried a scratch restore from a Time Machine backup, and it took almost two days to get reasonable working system, and several weeks after that before most of the little glitches were smoothed out. In fairness, my setup is a lot more complicated than the average user, but I also get the sense that most users are largely unaware of how tied they are to complicated configurations that they\u2019ve (consciously or otherwise) fine-tuned to their workflow over the course of years.<\/p>\n I also maintain a hundred or so Linux-based systems. I\u2019ve searched from time to time, but surprisingly I\u2019ve never found a SuperDuper-like utility for making bootable clones. It\u2019s long been on my list of things to create, but a recent People get cagey about backups. They want to be selective (who needs to be able to access three years of temporary cache files?). They want to conserve backup space. That\u2019s all well and good, but your bootable clone is not the place to do this. Just buy a backup drive that\u2019s as large or larger than your primary and back up everything<\/em>. You don\u2019t want to be scrambling to get back online and discover that a rule you created to save a few MB of drive space inadvertently blocked the backup of a critical file.<\/p>\n <\/a><\/p>\n This technique has been tested with Ubuntu 14.04, Ubuntu 18.04, Devuan ascii, as well as recent Arch releases. It should work with Debian-derived distros and other systems that use the WARNING!<\/strong> This will erase all data on whatever drive you specify. Specify the wrong drive, and you\u2019ll erase your source<\/em> instead of your destination. Be careful!<\/p>\n <\/a><\/p>\n <\/a><\/p>\n Remember that the \u201cdisaster\u201d in \u201cdisaster recovery\u201d can mean many things, from acts of nature to government seizures to theft or sabotage or facility breakdown. I keep two bootable clones of each machine and, each week, I swap them between two geographically-separate sites. That way, I always have a bootable clone that\u2019s less than two weeks old even if one location is completely lost. Of course, that\u2019s in addition to much-more-frequent No, I don\u2019t actually juggle 200+ clones. Many of my boxen are very small (think whiteboxed routers). I use a small stack of 2TB portable USB3 drives and create Unlike the Apple use case above, using clones to run from different hardware isn\u2019t quite as straightforward. Since the hardware doesn\u2019t come from a corporate monoculture, more differences exist than in the Macintosh ecosystem. Surprisingly, this hasn\u2019t been as big an issue as I expected, in spite of the fact that my infrastructure is built from fire-sale, castoff, and various other forms of junk computers ranging from Mac minis to repurposed doorstops. It is sometimes necessary to tweak In order to keep things as simple as possible, I have not enabled swap (though we did reserve a swap partition). Linux systems tend to degrade more gracefully when swap is enabled. The ArchWiki has a good discussion on how to enable swap<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":" A bootable clone is a disk that holds a complete copy of a running system that\u2019s ready to boot. Bootable clones can be a critical part of your backup strategy.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-189","post","type-post","status-publish","format-standard","hentry","category-coding"],"_links":{"self":[{"href":"https:\/\/looseassociations.com\/index.php?rest_route=\/wp\/v2\/posts\/189"}],"collection":[{"href":"https:\/\/looseassociations.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/looseassociations.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/looseassociations.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/looseassociations.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=189"}],"version-history":[{"count":14,"href":"https:\/\/looseassociations.com\/index.php?rest_route=\/wp\/v2\/posts\/189\/revisions"}],"predecessor-version":[{"id":539,"href":"https:\/\/looseassociations.com\/index.php?rest_route=\/wp\/v2\/posts\/189\/revisions\/539"}],"wp:attachment":[{"href":"https:\/\/looseassociations.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=189"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/looseassociations.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=189"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/looseassociations.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=189"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}systemd<\/code>-related disaster<\/a> left me with a crashed mission-critical server for over five days. That, combined with a horrible bug in the duplicity<\/code> backup system, resulted in more downtime than all of my systems combined over the previous ten years.<\/p>\nCurrent Options<\/h1>\n
\n
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Clonezilla requires that the system have a working optical drive<\/del>.<\/li>\nssh<\/code>). In my world, that means a certain amount of physical discomfort. I much prefer the comfort of working from my mother\u2019s basement, chugging Mountain Dew while my Dorito-dust covered fingers clack away on my sticky gaming keyboard.<\/li>\ncp<\/code>, tar<\/code>, or rsync<\/code> can make sure that you get all your files. The usual advice is then \u201cinstall a fresh system, and copy the important files from your backup to the new bootable system.\u201d Guess what: it won\u2019t work. Yes, you can copy your \/home<\/code> directory, but that won\u2019t restore any of your system configuration. Over time, you\u2019ve probably installed multiple software packages with multiple configuration files, perl and python modules, all scattered through the \/etc<\/code> and \/var<\/code> directories and configuration files, thoroughly mixed in with install-specific files and data that you can\u2019t just replace with information from the old system. You\u2019ll lose log files. You\u2019ll lose startup sequences. Unless you run a vanilla system (and I doubt any plain-vanilla users are here reading this) you\u2019ll be in for hours and hours of reconfiguration and figuring out which \u201cimportant\u201d files should be copied, and which must not be, and which configuration files need to be carefully merged with those on the new system.<\/li>\ndd<\/code>. I use and love dd<\/code>, and it meets my criterion for simplicity, but it has some real limitations.\n\n
dd<\/code>, I pretty much have to copy the entire 1.5TB which takes hours. Yes, I could re-partition the drive and only dd<\/code> the partition but then the clone wouldn\u2019t be bootable and I\u2019d lose the simplicity.<\/li>\nSimplicity is Key<\/h1>\n
Creating a Bootable Clone<\/h1>\n
GRUB2<\/code> bootloader.<\/p>\nGet Ready<\/h2>\n
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bash<\/code> shell; you need to be root so\u2026<\/li>\n<\/ul>\nsudo -s<\/code><\/p>\n\n
fdisk -l<\/code><\/p>\n\n
\/dev\/sdx<\/code>. So remember: whenever you see \/dev\/sdx<\/code>, be sure to replace the x with the appropriate device indicator.<\/li>\n<\/ul>\nFirst Time? Prepare the Bare Drive<\/h2>\n
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\/dev\/sdx<\/code> to your actual device designation. You might have to repeat the \u201cd\u201d command several times if there are multiple existing partitions. When in doubt, use defaults.<\/li>\n<\/ul>\nfdisk \/dev\/sdx<\/code><\/p>\n\n
Welcome to fdisk (util-linux 2.29.2).\r\nChanges will remain in memory only, until you decide to write them.\r\nBe careful before using the write command.\r\n\r\nCommand (m for help): d<\/strong><\/em>\r\nPartition number (1-3, default 3):\r\n\r\nPartition 3 has been deleted.\r\n[repeat until you get an error because all the partitions have been deleted]<\/strong><\/em>\r\n\r\nCommand (m for help): n<\/strong><\/em>\r\nPartition type\r\np primary (0 primary, 0 extended, 4 free)\r\ne extended (container for logical partitions)\r\nSelect (default p):\r\n\r\nUsing default response p.\r\nPartition number (1-4, default 1):\r\nFirst sector (2048-468862127, default 2048):\r\nLast sector, +sectors or +size{K,M,G,T,P} (2048-468862127, default 468862127): +512M<\/strong><\/em>\r\n\r\nCreated a new partition 1 of type 'Linux' and of size 512 MiB.\r\n\r\nCommand (m for help): t<\/strong><\/em>\r\nSelected partition 1\r\nPartition type (type L to list all types): XX<\/strong><\/em>\r\nChanged type of partition 'Linux' to 'EFI (FAT-12\/16\/32)'.\r\n\r\nCommand (m for help): n<\/strong><\/em>\r\nPartition type\r\np primary (1 primary, 0 extended, 3 free)\r\ne extended (container for logical partitions)\r\nSelect (default p):\r\n\r\nUsing default response p.\r\nPartition number (2-4, default 2):\r\nFirst sector (1050624-468862127, default 1050624):\r\nLast sector, +sectors or +size{K,M,G,T,P} (1050624-468862127, default 468862127): +213G\r\n[subtract the desired swap size from the total disk size; this was a 223GB disk as reported by fdisk, and I want about a 10GB swap]<\/strong><\/em>\r\n\r\nCreated a new partition 2 of type 'Linux' and of size 213 GiB.\r\n\r\nCommand (m for help): n<\/strong><\/em>\r\nPartition type\r\np primary (2 primary, 0 extended, 2 free)\r\ne extended (container for logical partitions)\r\nSelect (default p):\r\n\r\nUsing default response p.\r\nPartition number (3,4, default 3):\r\nFirst sector (447744000-468862127, default 447744000):\r\nLast sector, +sectors or +size{K,M,G,T,P} (447744000-468862127, default 468862127):\r\n\r\nCreated a new partition 3 of type 'Linux' and of size 10.1 GiB.\r\n\r\nCommand (m for help): t<\/strong><\/em>\r\nPartition number (1-3, default 3):\r\nPartition type (type L to list all types): XX<\/strong><\/em>\r\n\r\nChanged type of partition 'Linux' to 'Linux swap'.\r\n\r\nCommand (m for help): w\r\nThe partition table has been altered.\r\nCalling ioctl() to re-read partition table.\r\nSyncing disks.\r\n<\/pre>\n\n
apt install dosfstools<\/code>) to create the FAT partition.<\/li>\n<\/ul>\nmkfs.fat -F32 \/dev\/sdx1<\/pre>\n
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\/dev\/sdx2<\/code> appropriately.<\/li>\n<\/ul>\nmkfs.ext4 \/dev\/sdx2<\/code><\/p>\n\n
mkswap \/dev\/sdx3<\/pre>\n
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\/dev\/sdx2<\/code> first.<\/li>\n<\/ul>\nmount -t ext4 \/dev\/sdx2 \/mnt<\/code><\/p>\n\n
mkdir \/mnt\/dev
\nmkdir \/mnt\/dev\/pts
\nmkdir \/mnt\/sys
\nmkdir \/mnt\/proc<\/code><\/p>\nMount and Copy<\/h3>\n
\n
mount -t ext4 \/dev\/sdx2 \/mnt<\/code><\/p>\n\n
rsync<\/code>, if a clone already exists on this drive, it will incrementally update which should save some time.<\/li>\n<\/ul>\nrsync --archive --verbose --delete --exclude=\/dev --exclude=\/sys --exclude=\/proc --exclude=\/mnt -xx \/ \/mnt<\/code><\/p>\nInstall GRUB2<\/h3>\n
\n
mount --bind \/dev \/mnt\/dev
\nmount --bind \/dev\/pts \/mnt\/dev\/pts
\nmount --bind \/sys \/mnt\/sys
\nmount --bind \/proc \/mnt\/proc
\nmkdir \/mnt\/boot\/efi
\nmount \/dev\/sdx1 \/mnt\/boot\/efi
\nchroot \/mnt<\/code><\/p>\n\n
\/dev\/sdx<\/code> in two places<\/em> before executing these commands.<\/li>\n<\/ul>\ngrub-install \/dev\/sdx\r\ngrub-install --recheck \/dev\/sdx\r\nupdate-grub<\/pre>\n
Clean up
\/etc\/fstab<\/code><\/h3>\n\n
\/boot<\/code> or \/home<\/code> or for swap space. In order to keep things clean and simple, I\u2019ve made the clone into a monolithic file system. Unfortunately, the cloned \/etc\/fstab<\/code> might cause the system to fail to boot. These commands attempt to create an fstab<\/code> that\u2019s good enough to boot. (Swap might be important to you; see the note at the end of this article for information on re-enabling swap on a clone.)<\/li>\nfstab<\/code>.<\/li>\n<\/ul>\nmv \/etc\/fstab \/etc\/fstab.bak<\/code><\/p>\n\n
\/dev\/sdx2<\/code> that needs to be edited!<\/li>\n<\/ul>\necho -e \"UUID=`lsblk -no UUID \/dev\/sdx1`\\t\/\\text4\\tdefaults,noatime\\t0\\t1\" >\/etc\/fstab<\/code><\/p>\nClean Up and Reboot<\/h3>\n
\n
exit
\numount \/mnt\/boot\/efi \/mnt\/dev\/pts \/mnt\/dev \/mnt\/sys \/mnt\/proc \/mnt<\/code><\/p>\n\n
del<\/code> or esc<\/code> or F11<\/code> or F12<\/code> or whatever key allows you to change the BIOS or EFI boot device, and change it to the newly created disk<\/li>\n<\/ul>\nExpert Mode<\/h1>\n
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sudo -s\r\nfdisk -l\r\nfdisk \/dev\/sdx ### fixup\r\nmkfs.fat -F32 \/dev\/sdx1 ### fixup\r\nmkfs.ext4 \/dev\/sdx1 ### fixup\r\nmkswap \/dev\/sdx3 ### fixup\r\nmount -t ext4 \/dev\/sdx2 \/mnt ### fixup\r\nmkdir \/mnt\/dev \r\nmkdir \/mnt\/dev\/pts \r\nmkdir \/mnt\/sys \r\nmkdir \/mnt\/proc\r\nrsync --archive --verbose --delete --exclude=\/dev --exclude=\/sys --exclude=\/proc --exclude=\/mnt -xx \/ \/mnt\r\nmount --bind \/dev \/mnt\/dev \r\nmount --bind \/dev\/pts \/mnt\/dev\/pts \r\nmount --bind \/sys \/mnt\/sys \r\nmount --bind \/proc \/mnt\/proc \r\nchroot \/mnt\r\nmkdir \/boot\/efi\r\nmount \/dev\/sdx1 \/boot\/efi\/ ### fixup\r\ngrub-install \/dev\/sdx ### fixup\r\ngrub-install --recheck \/dev\/sdx ### fixup\r\nupdate-grub \r\nmv \/etc\/fstab \/etc\/fstab.bak\r\necho -e \"UUID=`lsblk -no UUID \/dev\/sdx1`\\t\/\\text4\\tdefaults,noatime\\t0\\t1\" >\/etc\/fstab ### fixup required\r\nexit \r\numount \/mnt\/boot\/efi \/mnt\/dev\/pts \/mnt\/dev \/mnt\/sys \/mnt\/proc \/mnt<\/pre>\n
<\/a>After Words<\/h1>\n
rsync<\/code> backups between sites and archiving cloud backups. Back up in depth \u2014 it\u2019s good for your health.<\/p>\nrsync<\/code> images in separate directories under root. If I need a clone, I can either copy the subdirectory to root on a fresh drive, or just move the subdirectory up to root. I then install GRUB2<\/code> and go.<\/p>\n\/etc\/fstab<\/code> or to change networking parameters to switch from eth0<\/code> to eth1<\/code> or the like.<\/p>\n