I had a super fast but small SSD and didn’t know what to do with it, so I was playing with caching slow spinning LVM drives. It worked pretty good, but I got interrupted and came back a few weeks later to upgrade the OS. I forgot about the caching LVM, updated the packages in preparation for the OS upgrade, then rebooted. The LVM cache modules weren’t in the initfs image and it didn’t boot.
I should know better. I used to roll my own kernels since Slackware 1.0. I’ve had build initfs images for performance tweaks. Ugh!
Where’s my rescue disk?
A Gentoo LiveUSB and some chroot would save your day!
Adding a netboot.xyz EFI boot menu entry can be useful if you do not need a live system often and do not have a USB stick when you do.
But don’t you need a wired network connection for this to actually work?
I have only tried it with wired but it uses ipxe and that is supposed to work with Android USB tethering too to bridge to other kinds of network access.
I have the Debian netinst disk, but it doesn’t include the dm-cache modules, so I downloaded the live DVD last night. I only get about an hour a day to work on stuff.