How to Change Share Options on an NFS File System

If you use the rw, rw=, ro, or ro= options to the share -o command, NFS fault monitoring works best if you grant access to all the physical hosts or netgroups associated with all Sun Cluster servers.

If you use netgroups in the share(1M) command, add all of the Sun Cluster host names to the appropriate netgroup. Ideally, grant both read and write access to all the Sun Cluster host names to enable the NFS fault probes to do a complete job.

Before you change share options, read the share_nfs(1M) man page to understand which combinations of options are legal.

1. Become superuser on a cluster node.

2. Turn off fault monitoring on the NFS resource.

   # scswitch -n -M -j resource-name

   -M

   Disables the resource monitor.

3. Execute your proposed new share(1M) command.

   Before editing the dfstab.resource-name file with new share options, execute the new share(1M) command to verify that the combination of options is valid.

   # share -F nfs [-o] specific_options [-d "description"] pathname

   -F nfs

   Identifies the file system type as NFS.

   -o specific_options

   Specifies an option. We suggest rw, which grants read-write access to all clients.

   -d description

   Describes the file system being added.

   pathname

   Identifies the file system being shared.

   If the new share(1M) command fails, immediately execute another share(1M) command with the old options. When the new command executes successfully, go on to the next step.

4. Edit the dfstab.resource-name file with the new share options.

   The format of this file is exactly the same as the format used in /etc/dfs/dfstab. Each line consists of a share(1M) command.

5. (Optional) If you are removing a path from the dfstab.resource-name file, execute the unshare(1M) command, then remove the share(1M) command for the path from the dfstab.resource-name file.

   # unshare [-F nfs] [-o rw] pathname # vi dfstab.resource-name

   -F nfs

   Identifies the file system type as NFS.

   -o options

   Specifies the options that are specific to NFS file systems.

   pathname

   Identifies the file system being made unavailable.

6. (Optional) If you are adding a path to or changing an existing path in the dfstab.resource-name file, verify that the mount point is valid, then perform Step 3 and Step 4.

7. Enable fault monitoring on the NFS resource.

   # scswitch -e -M -j resource-name