Unable to access submounts from NFS server after upgrading
Issue:
When mounting an exported tree with NFSv4, sub-directories within the entire tree should be accessible but are not. When attempting to access any directory below the top level export the following error occurs:
ls -l /mnt/server/a
ls: /mnt/server/a: Not a directory
Environment:
- NFS client
- Red Hat Enterprise Linux 5.8 (kernel 2.6.18-308.el5)
- NFS Server
- Netapp: Data ONTAP 7.2 and above
- OpenSolaris NFS server
- RHEL6.2 NFS server
- Directory exported from server contains subdirectories on other filesystems not separately exported
Resolution:
Update to kernel-2.6.18-308.4.1.el5 (RHSA-2012:0480-1) or newer.
# yum update kernel
Root Cause:
Kernel 2.6.18-308.4.1.el5 includes a change where nfs_follow_mountpoint() was replaced with nfs_d_automount.
Permanent fixes are tracked in
- bugzilla 801726 for the current RHEL-5.8
- bugzilla 798809 for the upcoming RHEL-5.9