Thanks for the response Lennart. I think something like this should be added to the man page. I opened a bug report for this.
Michael 2016-02-03 22:58 GMT+01:00 Lennart Poettering <[email protected]>: > On Wed, 03.02.16 22:03, Michael Biebl ([email protected]) wrote: > >> Hi everyone >> >> I wonder that emergency.target/emergency.service/emergency mode is good for. >> >> Afaics, it doesn't offer anything that rescue mode doesn't also offer. >> I find this situation a bit confusing. >> >> Can anyone enlighten me why we need two different modes which are >> basically the same? > > Emergency mode means the only running process is a shell, besides > systemd itself. > > rescue mode means all early-boot services have been started, all > mounts have been established, and then gives you a shell. > > emergency mode is a bit like booting with init=/bin/sh except that you > actually have systemd up properly, and can start services bit-by-bit > if you like. emergency mode is also entered if fsck fails, as in that > case rescue mode is unachievable, as we cannot mount the failed > disks... > > rescue mode is usually what admins want to boot into for single-user > maintainance tasks. The only reason when you want to boot into > emergency mode instead if you have some fuckup with your disks. > > Note that sysvinit had the very same distinction, though the feature > is little-known. Booting sysvinit with "emergency" on the kernel > cmdline would give you just sysvinit as PID1 plus /bin/sh forked > off. Booting sysvinit with "1" on the kernel cmdline would give you > runlevel 1 services including mounts, and then a shell. In fact, > systemd understand the same kernel cmdline keywords and does the right > thing... > > Lennart > > -- > Lennart Poettering, Red Hat -- Why is it that all of the instruments seeking intelligent life in the universe are pointed away from Earth? _______________________________________________ systemd-devel mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/systemd-devel
