Rescuing Linux: Difference between revisions
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echo b > /proc/sysrq-trigger</pre> | echo b > /proc/sysrq-trigger</pre> | ||
Alt+SysRq+B will accomplish this at the terminal if sysrq reboot is enabled. Unlike <tt>reboot</tt>, there will be no syncing and unmounting of disks. | Alt+SysRq+B will accomplish this at the terminal if sysrq reboot is enabled. Unlike <tt>reboot</tt>, there will be no syncing and unmounting of disks. | ||
==moving a root filesystem + bootloader== | |||
Ideally, mount the source filesystem <tt>ro</tt>, so it's not being modified while you copy. Start assuming a clean destination filesystem (otherwise, wipe it). Using the <tt>-a</tt> flag, <tt>cp</tt> basic toplevel directories *but do not cross filesystem boundaries on the source* (i.e. if <tt>/home</tt> is on its own filesystem, do not include it below; this includes <tt>/boot/efi</tt>). Any that you skip in this fashion ought have their mountpoints created; add them to the <tt>mkdir</tt> below: | |||
<pre> | |||
cp -a SOURCE/{bin,boot,etc,home,lib*,root,sbin,usr} DEST/ | |||
mkdir -p DEST/{dev,proc,var/tmp,tmp} | |||
ln -s /run DEST/var/run | |||
ln -s /lock DEST/var/lock | |||
chmod 1777 DEST/{var/tmp,tmp} | |||
</pre> | |||
<b>ESP, bootloader, initramfs...</b> | |||
==External links== | ==External links== | ||
* Debian wiki page for [https://wiki.debian.org/initramfs initramfs] | * Debian wiki page for [https://wiki.debian.org/initramfs initramfs] | ||
* Kernel documentation for [https://www.kernel.org/doc/html/latest/filesystems/ramfs-rootfs-initramfs.html Ramfs, Rootfs, and Initramfs] | * Kernel documentation for [https://www.kernel.org/doc/html/latest/filesystems/ramfs-rootfs-initramfs.html Ramfs, Rootfs, and Initramfs] | ||