Messages in this thread |  | | | From | "Eric S. Mountain" <> | | Subject | Re: Eject, Rebooting, Shortcuts, kernel bloat | | Date | Sun, 31 Mar 1996 21:11:06 +0100 (BST) |
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Laszlo Vecsey ecrivit: > Is there a safe way to reboot the system, making absolutely sure that the > file systems get unmounted before the system is restarted? I always have > one partition that needs to be re-e2fscked each time on startup, probably > because the processes that were using it were not terminated properly > during shutdown and the filesystem wasn't unmounted and marked as clean.
This is a vagary I have encountered before: check out the Tips-HOWTO: [ Quote from Tips-HOWTO ] 2.4. How to avoid fscks caused by "device busy" at reboot time. Jon Tombs, jon@gtex02.us.es
If you often get device busy errors on shutdown that leave the filesystem in need of an fsck upon reboot, here is a simple fix:
To /etc/brc or /sbin/brc, add the line
mount -o remount,ro /mount.dir
for all your mounted filesystems except /, before the call to umount -a. This means if, for some reason, shutdown fails to kill all pro- cesses and umount the disks they will still be clean on reboot. Saves a lot of time at reboot for me [ End quote ]
> And why is it that certain processes can go dead and not even kill -9 can > remove them? How about having a ctrl-scroll-lock option that would list
These are called zombie processes. They are already dead, so you can't kill them. I think they occupy zero-memory so apart from an ugly entry in your ps -aux they won't do much harm. See the comp.unix.shell FAQ "How do I get rid of zombie processes that persevere?" for a discussion on this.
> all the processes and allow you to move up and down with a scrollbar, > highlight the process you want (giving status information) and zap it if > need be. Also, is it possible to have a process running that would NOT be > listed with ps -x? I've heard it could be done. I would feel much better > if the kernel could tell me exactly which processes are running, and give > me the ability to zap or -SIGHUP them with ease.
ps -ax gives you a complete listing. No need to bloat the kernel with this kind of work.
Also, you mean you want to give anyone the ability to kill any process!?
> I don't see any security risk with having this kind of option freely > available through a hotkey (i.e., even if root isn't logged in on a VC)
I see you _are_ serious. Wow.
> because anybody can hit ctrl-alt-del and insert a bootdisk and get full
Not if you disable booting from A: in the CMOS and put a password on the CMOS setup. (OK, so they can open the box, short the CMOS battery... ;)
> access. Actually, maybe we need a compile option to remove ctrl-alt-del
No need for a compile-option: edit your inittab file to disable CAD: you want to comment-out the following:
# What to do when CTRL-ALT-DEL is pressed. ca::ctrlaltdel:/sbin/shutdown -t1 -r now
:E -- Eric S. Mountain - eric@minouche.demon.co.uk
No matter what occurs, someone believes it happened according to his pet theory
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