How to Remove a Cluster File System

You remove a cluster file system by merely unmounting it. If you want to also remove or delete the data, remove the underlying disk device (or metadevice or volume) from the system.

Note - Cluster file systems are automatically unmounted as part of the system shutdown that occurs when you run scshutdown(1M) to stop the entire cluster. A cluster file system is not unmounted when you run shutdown to stop a single node. However, if the node being shut down is the only node with a connection to the disk, any attempt to access the cluster file system on that disk results in an error.

The prerequisites to unmount cluster file systems are:

• Superuser privilege on a node in the cluster.

• The file system cannot be busy. A file system is considered busy if a user is in a directory in the file system, or if a program has a file open in that file system. The user or program could be running on any node in the cluster.

1. Become superuser on any node in the cluster.

2. Determine which cluster file systems are mounted.

   # mount -v

3. On each node, list all processes that are using the cluster file system, so you know which processes you are going to stop.

   # fuser -c [ -u ] mountpoint

   -c	Reports on files that are mount points for file systems and any files within those mounted file systems.
   -u	(Optional) Displays the user login name for each process ID.
   mountpoint	Specifies the name of the cluster file system for which you want to stop processes.

4. On each node, stop all processes for the cluster file system.

   Use your preferred method for stopping processes. If necessary, use the following command to force termination of processes associated with the cluster file system.

   # fuser -c -k mountpoint

   A SIGKILL is sent to each process using the cluster file system.

5. On each node, verify that no processes are using the file system.

   # fuser -c mountpoint

6. From just one node, umount the file system.

   # umount mountpoint

   mountpoint

   Specifies the name of the cluster file system you want to unmount. This can be either the directory name where the cluster file system is mounted, or the device name path of the file system.

7. (Optional) Edit the /etc/vfstab file to delete the entry for the cluster file system being removed.

   Perform this step on each cluster node that has an entry for this cluster file system in its /etc/vfstab file.

8. (Optional) Remove the disk device group/metadevice/plex.

   See your volume manager documentation for more information.

Example--Removing a Cluster File System

The following example removes a UFS cluster file system mounted on the Solstice DiskSuite/Solaris Volume Manager metadevice /dev/md/oracle/rdsk/d1.

# mount -v
...
/global/oracle/d1 on /dev/md/oracle/dsk/d1 read/write/setuid/global/logging/largefiles 
# fuser -c /global/oracle/d1
/global/oracle/d1: 4006c
# fuser -c -k /global/oracle/d1
/global/oracle/d1: 4006c
# fuser -c /global/oracle/d1
/global/oracle/d1:
# umount /global/oracle/d1
 
(on each node, remove the highlighted entry:)
# vi /etc/vfstab
#device           device        mount   FS      fsck    mount   mount
#to mount         to fsck       point   type    pass    at boot options
#                       
/dev/md/oracle/dsk/d1 /dev/md/oracle/rdsk/d1 /global/oracle/d1 ufs 2 yes global,logging
[Save and exit.]

Note - To remove the data on the cluster file system, remove the underlying device. See your volume manager documentation for more information.

How to Check Global Mounts in a Cluster

The sccheck(1M) utility verifies the syntax of the entries for cluster file systems in the /etc/vfstab file. If there are no errors, nothing is returned.

Note - Run sccheck after making cluster configuration changes, such as removing a cluster file system, that have affected devices or volume management components.

1. Become superuser on any node in the cluster.

2. Check the cluster global mounts.

   # sccheck

Administering Disk-Path Monitoring

Disk path monitoring (DPM) administration commands enable you to receive notification of secondary disk-path failure. Use the procedures in this section to perform administrative tasks that are associated with monitoring disk paths. Refer to "Key Concepts for Administration and Application Development" in Sun Cluster 3.1 Concepts Guide for conceptual information about the disk-path monitoring daemon. Refer to the scdpm(1M) man page for a description of the scdpm(1M) command options and related commands. Refer to the syslogd(1M) man page for logged errors that are reported by the daemon.

Note - Disk paths are automatically added to the monitoring list monitored when I/O devices are added to a node by using the scgdevs(1M) or scdidadm(1M) commands. Disk paths are also automatically unmonitored when devices are removed from a node by using Sun Cluster commands.

Table 4-5 Task Map: Administering Disk-Path Monitoring

The procedures in the following section issue the scdpm(1M) command with the disk-path argument. The disk-path argument is always constituted of a node name and a disk name. The node name is not required and defaults to all if none is specified. The following table describes the conventions that are used for naming the disk path.

Note - Use of the global disk-path name is strongly recommended, because the global disk-path name is consistent throughout the cluster. The UNIX disk-path name is not consistent throughout the cluster. The UNIX disk path for one disk can differ from cluster node to cluster node. The disk path could be c1t0d0 on one node and c2t0d0 on another node. If you use UNIX disk-path names, use the scdidadm -L command to map the UNIX disk-path name to the global disk-path name before issuing DPM commands. See the scdidadm(1M) man page.

Table 4-6 Sample Disk-Path Names