mount_ccase

Mount and unmount commands for VOBs and the viewroot directory

Applicability

Product

Command type

ClearCase®

command

Platform

UNIX

Linux

Synopsis

The mount_mvfs program must never be invoked explicitly. Instead, use cleartool mount, which invokes the correct architecture-specific mount command.

Description

This reference page describes the mechanisms that mount VOBs as file systems of type MVFS (the ClearCase multiversion file system).

Automatic VOB activation at system startup

At system startup, the architecture-specific ClearCase startup script (see the init_ccase reference page) issues a mount –all command. This activates on the local host all the VOBs that are registered as public in the local host's network region of the ClearCase VOB registry. During this procedure, the architecture-specific mount command performs the actual work of mounting the VOB as a file system of type MVFS. (The command is actually a symbolic link to ccase-home-dir/etc/mount_mvfs.)

VOB activation after system startup

After system startup, a mount command can be used to activate or reactivate any VOB that is listed in the tags registry.

  • root can activate any VOB in this way.
  • Another identity can activate any public VOB, or any private VOB owned by that identity.

Automatic VOB deactivation at system shutdown

At system shutdown, the architecture-specific ClearCase startup script is invoked with the stop option to execute the ClearCase shutdown procedure. As part of this procedure, a umount –all command deactivates all VOBs currently active on the local host. On all supported platforms except for AIX®, umount –all invokes the standard umount(1M) utility directly. On AIX, umount –all invokes the architecture-specific mount command /sbin/helpers/mvfsmnthelp with U as its first argument, and /sbin/helpers/mvfsmnthelp then invokes umount(1M).

Individual VOB deactivation

While ClearCase is running, a umount command can be used to deactivate any mounted VOB:

  • root can deactivate any VOB in this way.
  • A non-root user can deactivate any public VOB, or any private VOB owned by that user.