Messages in this thread | | | Date | Mon, 05 Feb 2001 03:08:50 +0000 | From | "Michael D. Crawford" <> | Subject | OK to mount multiple FS in one dir? |
| |
I was groping around my FAT/NTFS directories from Linux, mounting and unmounting them into /mnt, and was suprised at some point that I got the message "/dev/sda5 already mounted or /mnt busy". (I'm using a SCSI disk, use hda* for IDE).
Upon further examination, I found that I'd accidentally mounted /dev/sda1 (VFAT) on /mnt while /dev/sda5 (NTFS) was still mounted there. The NTFS files remained invisible until I'd unmounted /dev/sda1 and then I could see them again.
This is with the 2.4.1 kernel on a Pentium III machine with an Adaptec 29160 SCSI controller.
I found I could mount three partitions on /mnt, and they'd all show up as mounted at /mnt in the "mount" command, but if I unmounted one of them (only tried with the currently visible one), then it appeared that there were no filesystems mounted there, but I could continue umounting until the other two were gone.
I'm suprised this works. Note that the kernel rejected an attempt to mount a filesystem that was already mounted, but not to mount a filesystem at a point that was already in use. It looks like there is a stack of mounts on the mount point.
Looking at Documentation/Changes, I see that I need util-linux 2.10o. I had 2.10l. But I had the 2.10r util-linux sources on my machine and installed mount and umount from it, and I find that it gets it right mostly when I mount and unmount multiple things, with the exception that if /dev/sda5 was mounted before /dev/sda1, then if I give the command "umount /dev/sda5", sda1 is the one that gets unmounted rather than sda5, so it takes the most recently mounted filesystem rather than the one you specify.
Michael D. Crawford GoingWare Inc. - Expert Software Development and Consulting http://www.goingware.com/ crawford@goingware.com
Tilting at Windmills for a Better Tomorrow.
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
| |