From: hans@mo.hobby.nl (Hans Oey) Subject: Re: Is (e2)fsck dangerous?? Date: Wed, 7 Apr 1993 20:08:18 GMT
jwinstea@fenris.claremont.edu (Jim Winstead Jr.) writes:
>In article <1993Apr4.184748.8798@mo.hobby.nl> hans@mo.hobby.nl (Hans Oey) writes:
> What's wrong with rebooting without sync after fsck has corrected
> the root filesystem? It seems more easy then booting from a
> readonly file system and remounting it afterward.
>How is going through the whole rebooting process easier than simply
>waiting until *after* the fsck has completed before you allow any
>writes to the root filesystem?
One way or another should be easy to run, even unattended.
I meant that booting from a readonly file system would
require more changes. (Being able to boot from a write
protected floppy would be great.)
>When fsck is done and closes the device it's worked on, the device
>gets synced out to disk. Otherwise doing all the changes would be
>pretty pointless (because they'de be lost when you reboot).
I know fsck itself should sync before exiting. But after that
you can just hard reset the machine without any fancy shutdown
or reboot programs.
>There's nothing to prevent any other program from also making changes
>to the root filesystem (or any other mounted filesystem) while you are
>doing the fsck. It's possible that some other program will be making
>changes that clash with what fsck does so you end up with a bigger
>mess than you started.
The point is that init should run fsck on the root fs first
(before /etc/rc or any getty). So there won't be any
other program.
>The new approach is very simple, quite standard, and makes a lot of
>sense. Rebooting is just silly, because it's not as safe.
Hope it will be simple to develop. Rebooting is
safe if done right. (SVR4 wasn't that bad :-)