On RedHat 5.2, I had set up a system with the CD-ROM mounted as /cdrom, 'user' mount privileges enabled, and /cdrom NFS exported to an HP-UX 10.20 system. Worked fine. At RedHat 6.0, this no longer works. Specifically: 1. The HP-UX system cannot see the contents of the CD, even though both the RedHat and HP sides report a successful mount. In particular, "ls /net/redhatbox/cdrom" on the HP returns no output (where /net/redhatbox/cdrom is the NFS mount point on the NFS client). No errors appear on the console or in any logs on either system. 2. After a successful umount of the CD from the NFS client, the RedHat system will not allow an unmount of the physical CD unless NFS is stopped first; '/cdrom: device busy' is the error returned otherwise. This is the case when the only NFS mount is from a non-HP-UX system as well. I can export any other file system from RedHat to the HP-UX box without trouble. I have tried knfsd-1.4.7 from the Rawhide distribution but there was no change. I have tried /sbin/rpcdebug but it complains that /proc/net/rpc/debug doesn't exist.
I also see such things on my RedHat 6.1. When I mount _any_ filesystem, export them into NFS, mount exported NFS shares, succesfully use them, successfully unmount NFS shares, then I try to unmount filesystem, ang got 'device busy'. After stopping and starting NFS daemon I was able to unmount my filesystems. Simple restarting NFS daemon does not have effect. I must stop and start nfsd again.
assigned to johnsonm
Is this problem still occuring in Red Hat Linux 7.3/8.0? I could not duplicate the exact problem, but may not be following the same steps as yours.
Closing this out as result of bit-rot.