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.