Subject: kern/564: msdosfs incompatibility with NFS
To: None <>
From: None <>
List: netbsd-bugs
Date: 11/08/1994 14:35:05
>Number:         564
>Category:       kern
>Synopsis:       msdosfs is incompatible with NFS
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    gnats-admin (Kernel Bug People)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Nov  8 14:35:02 1994
>Originator:     Mike Hartman
Human Designed Systems, Inc.
>Release:        current
System: SunOS hdssun1 4.1.3 1 sun4m
Architecture: sun4

	Since msdosfs does not update the modification times for directories,
	it is incompatible with NFS.  Some NFS clients cache info on
	directories and files and the file modification time is used to
	determine if the the cached info is valid.
	When an msdosfs filesystem is NFS mounted from a Sun running
	SunOS 4.1.3, the following example shows the problem:

	sun>cd subdir1/subdir2
	sun>cd ..
	sun>mv subdir2 ..
	sun>cd ../subdir2
	sun>cd ..
	current directory is 'subdir1'.

	One possible solution is for msdosfs to update the file modification
	times for directories on the disk.  Would MS-DOS complain?  If so,
	the file modification times for directories' RAM entries (denodes)
	could be updated without modifying the data on the disk.