Updated nfs-utils packages that fix several bugs and add various enhancements are now available for Red Hat Enterprise Linux 6.
The nfs-utils packages provide a daemon for the kernel Network File System (NFS) server and related tools, which provides better performance than the traditional Linux NFS server used by most users. These packages contain the mount.nfs, umount.nfs, and showmount programs.
- Prior to this update, the nfsiostat utility was run in the background with the stdout stream redirected to a file. As a consequence, the data was not displayed in a timely matter. This update clears stdout periodically to ensure the buffered output of nfsiostat does not get lost if the nfsiostat process is terminated.
- The nfs-utils packages were moved to an in-kernel keyring to store the ID mappings needed for NFSv4. However, the kernel key is too small for large enterprise environments. With this update, the nfsidmap utility, used by the kernel to do ID mapping, has been changed to use multiple keyrings.
- Previously, the rpc.idmapd name mapping daemon returned a warning message after failing to open communication with a client mount. As the warning message was harmless and unnecessary, rpc.idmapd now displays the message only if the user passes the "--verbose" option on the command line.
- The starting of the rpc.statd utility caused a creation of an extra privileged UDP socket. As a consequence, rpc.statd listened on a random port on all the interfaces, which is required only for internal communication with the rpc.lockd utility. With this update, rpc.statd no longer opens an extra socket in the described situation, and instead opens an extra random port on the loopback address only.
- The starting of the rpc.statd utility caused messages being flooded to the log. With this update, the socket is kept open until another one is found. As a result, the same port is not reused, and messages are no longer flooding the log in the described situation.
- When root squashing was enabled and world execute permissions were disabled, using the "-o remount" option of the mount utility caused the mount attempt to fail. This update fixes the chk_mountpoint() function, and the mount utility now checks only execute permissions for unprivileged users, thus fixing this bug.
- When the rpc.gssd daemon was started, a zero lifetime was sent to the kernel, which then guessed and used the default lifetime. To fix this bug, the correct lifetime is now passed to the kernel, which uses it for timeouts in GSS contexts.
- Previously, the rpcdebug utility did not work correctly when used with the NFS module and the "state" option. This update allows the "state" option to be used with the NFS module, and NFS state debugging can now be set as expected.
- Previously, machines with multiple disks made the rpc.mountd utility use 100% of the CPU for 30 to 40 minutes, needlessly scanning the disks. The libblkid daemon usage has been optimized, and rpc.mountd no longer causes downtime in this scenario.
- Due to a wrong indentation in its code, the nfsiostat utility failed to start. This update adds the correct indentation, and nfsiostat now starts as expected.
In addition, this update adds the following
- This update enhances the nfsmount.conf file manual page to include syntax for mount options. Now, the reader has a better understanding on how to set variables in the configuration file.
- IPv6 is now a supported address type, and the exportfs utility can thus use IPv6 addresses to export file systems.
- This update adds descriptions on what each value of the column in the output of the nfsiostat utility means.
Users of nfs-utils are advised to upgrade to these updated packages, which fix these bugs and add these enhancements. After installing this update, the nfs service will be restarted automatically.