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doublefailure 03-27-2002 07:52 PM

what is devfs?
 
hi all

several days ago, it seems like etc/fstab changed itself..
how do i correct this?

here's my "mount -a" and "/etc/fstab"

[root@localhost mysql]# mount -a
mount: /dev/devfs already mounted or /dev busy
mount: according to mtab, devfs is already mounted on /dev
mount: No medium found


[root@localhost mysql]# cat /etc/fstab
/dev/hda5 / ext2 rw,noatime 0 0
/dev/devfs /dev devfs defaults 0 0
/dev/hda1 /mnt/windows vfat defaults 0 0
/dev/hda8 /home/eugene/data ext2 rw,noatime 0 0
/dev/scd0 /mnt/cdrom iso9660 ro,user,auto,unhide
none /proc proc defaults 0 0
/dev/hda10 /home ext2 rw,noatime 0 0
/dev/hda9 /usr ext2 rw,noatime 0 0
/dev/hda7 /boot ext2 rw,noatime 0 0
[root@localhost mysql]#

another short question...
for /boot /home /usr,
i used mount option rw,noatime 0 0
just because it was the option for /
am i safe(?) with this?

thank you

trickykid 03-27-2002 09:24 PM

not totally familiar with mandrake, but i know you should be able to edit fstab and take out the entry for /dev/devfs with no problem. also, it mentioned it was already mounted in mtab..
what does your mtab file look like ?? most likely it has an entry in there for that /dev/devfs

-trickykid

doublefailure 03-28-2002 04:41 AM

hi..

thank you..

actually, i don't know about mtab..
i know kernel mount all devices in fstab..

what is mtab?
llist of devices which are currently mounted?
--hmm..this does not seem to be a correct answer..

thank you..

here's my mtab
------
[eugene@localhost eugene]$ cat /etc/mtab
/dev/hda5 / ext2 rw,noatime 0 0
none /proc proc rw 0 0
devfs /dev devfs rw 0 0
/dev/hda1 /mnt/windows vfat rw 0 0
/dev/hda10 /home ext2 rw,noatime 0 0
/dev/hda9 /usr ext2 rw,noatime 0 0
/dev/hda7 /boot ext2 rw,noatime 0 0
/proc/bus/usb /proc/bus/usb usbdevfs rw,devmode=0664,devgid=43 0 0
/dev/hda8 /home/eugene/data ext2 rw,noatime 0 0

acid_kewpie 03-28-2002 04:52 AM

well, your fstab is in a bit of a mess, i'd recoommend chaning it to

Code:

/dev/hda5  /              ext2  defaults  1 1
/dev/devfs  /dev            devfs  defaults  0 0
/dev/hda1  /mnt/windows    vfat  defaults  0 0
/dev/hda8  /home/eugene/data ext2 defaults  1 1
/dev/scd0  /mnt/cdrom  iso9660  ro,user,auto,unhide
none        /proc          proc  defaults  0 0
/dev/hda10  /home          ext2  defaults  1 1
/dev/hda9  /usr            ext2  defaults  1 1
/dev/hda7  /boot          ext2  defaults  1 2

all thoses 0 0's will mean the system isn't checked properly if it crashes.

when does this error message actually appear? IS it a problem? DevFS is a new system that will automatically create hte device references in /dev, replacing the current system of just having every imaginable device block permanantly on the system.

Thymox 03-28-2002 06:05 AM

It's pretty damn helpful aswell. Personally I prefer having just the entries: hda1,3,5,6,7,8,9,10,11,12,13, hdc, hdd, hdf4 instead of hunting (or trying to remember) for them from all the possible combinations.

doublefailure 03-28-2002 04:31 PM

thank you...

the error message shows up at boot time..
(or u mean more precisely?..)
actually, i don't think there's a problem besides the warning message..

by the way..
create hte devices rather than permanent files?

maybe i'm too ignorant to understand for u to explain it to me..
then it's ok, i'll catch up later maybe..
=)

Sixpax 03-28-2002 05:10 PM

I wouldn't use "noatime" at all on any of your filesystems unless disk performance is critical to whatever you are doing.

BTW, "0 0" stands for 2 different things... the first "0" tells the system which filesystems to dump in the event of a crash... the second "0" is used by fsck when you reboot your system to tell what order to check your filesystems. I wouldn't recommend having the last field set to "0" (which disables checking) ... that's like walking a tight-rope without a net.


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