| From: Russell via talk <talk@gtalug.org> | On April 11, 2018 7:02:56 PM EDT, "D. Hugh Redelmeier via talk" <talk@gtalug.org> wrote: | When I first started my switch from DOS to *nix, I was told you | absolutely don't want to run two versions of init on the same machine. I | believe this is why userland programming uses telinit. It seems to me | that not letting different distros share a home is a pretty sound idea, | even if it is based on superstition. | | I forget the exact reasons I was given for always using telinit. However | given the fine granularity and ballistic nature of the bits and dword | bytes, I assume that it could be catastrophic to request pid1 and | receive pid 1001. The audit trail to follow for recovery would be hard | to follow without being able to distinguish the id as being from | userland rather than kernelspace. I don't understand this at all. Perhaps it doesn't matter now that we all use systemd. I don't even have local man pages for this stuff. There could only be one init process (PID 1). But you could issue "init" as a command or "telinit" as a command. Both would do stuff and then tap the init process on the shoulder (using signals) to change its state. The init command was in the original Unix systems, not telinit. 7th Edition doesn't have telinit. Something later (System 3? BSD?) introduced telinit. | >Technically you can have more than one EFI System Partition on a drive | >but don't do this. I did this by accident and had a few problems. | | Out of curiosity, could you say what type of problems they were? I mostly don't remember. The computer wasn't mine and so I didn't get to observe it systematically. | >Windows cannot handle this case and firmware setup screens may be no | >better. I don't know of any upside. That lists two of the problems. I accidentally had a fresh Fedora install create a second EFI System Partition. It was a too-easy mistake to make ("a poor workman blames his tools"). I never understood why grub offered me the choices it did since subsequent Fedora updates didn't always use the same ESP as the UEFI Firmware booted from. I never understood how to control either in a way that stuck. Once I knew what the problem was, and had enough time, I fixed it rather than played with it. I booted from a live stick, copied things I wanted from the second ESP to the first, and denatured the second so it would not be found by the firmware or the OS. I must have updated the UUID of the /etc/fstab entry for /boot/efi. I chose to keep the ESP that Windows knew about because changing Windows' mind about something like that is hard.