Starting and stopping safely
Amiga UNIX keeps data in memory and writes it to disk later. Switching off a running system can leave the file systems to be repaired at the next boot. Always halt it first.
Switching off
As root, logged in on the console (a change of run level asked for over telnet can stall):
init 0
It stops the services, then halts. Wait for The system is halted; you may reboot or turn off
power., then 10 seconds more, and switch off. shutdown -i0 -g0 -y does the same (tested in
emulation on 1.1).
If it does not halt and the system stays up:
sync; sync; /sbin/uadmin 2 0
This halts at once, without stopping the services first. Over telnet your session simply ends:
that is the halt succeeding. Wait 10 seconds, then switch off.
Restarting
On a real 68060 (the Z3660): never reboot or shutdown -i6. The Z3660 cannot reset the CPU
cleanly; it may not start again until you switch off and on. Halt as above, then switch off and on.
On a 68030, halting and switching off and on is the tested way as well (shutdown -i0 -g0 -y halts
cleanly, tested in emulation). A software reboot is not tested on 1.1; if you reboot, do it from a
root shell on the console, never over telnet: there it can stall until you switch off.
After a crash or a power cut
Switch off and on. The next boot checks the file systems and repairs them; that is expected. When a halt was clean, the check finds nothing to repair.
A new kernel on trial is not used up by that repair restart: see boot recovery.