Technical data

Managing Storage Media
9.13 Using Mount Verification for Recovery
9.13.2.5 Canceling Mount Verification
You can cancel a mount verification request in one of the following ways:
• Dismount the volume with the DCL command DISMOUNT from a process
that is not hung.
• If the device is off line, allow mount verification to time out. The default time
limit for tapes is 600 seconds (10 minutes); for disks, it is 3600 seconds (1
hour). However, you can use the system parameter MVTIMEOUT (for disk)
or TAPE_MVTIMEOUT (for tape) to set the value to whatever you want.
When the time expires, the system automatically cancels the pending mount
verification. Note that a mount verification initiated by a write-lock condition
does not time out.
• Invoke a special canceling routine, IPC, from the console terminal.
The following section describes the first method, using the DISMOUNT command,
in more detail. See Section 9.14.2 for details about using the last method, IPC, to
cancel mount verification.
Using the DISMOUNT Command
To dismount a volume:
1. Log in at another terminal, or use any logged-in terminal that has access to
the volume. (It does not need to be an operator terminal.)
2. Enter the DISMOUNT/ABORT command for the volume. (To use the /ABORT
qualifier with a volume that is not mounted group or system, you must have
volume ownership or the user privilege VOLPRO.)
If your system is in an OpenVMS Cluster environment, also specify the
/CLUSTER qualifier.
When you cancel a pending mount verification by dismounting the volume,
OPCOM issues a message in the following format:
%%%%%%%%%%%% OPCOM, <dd-mmm-yyyy hh:mm:ss.cc> %%%%%%%%%%%
Mount verification aborted for device <device-name>.
If you do not have access to the volume, you receive an error message. You
can try again if you can find an appropriate process to use. If your process
hangs, the system file ACP is hung, and you cannot use this technique to
cancel mount verification.
3. When the cancellation is complete, remove the volume from the drive.
9.14 Using Interrupt Priority Level C (IPC)
IPC is a special program that issues a software interrupt to gain the attention
of the console terminal. You can use IPC commands to adjust quorum in an
OpenVMS cluster, to cancel mount verification, or to enter the debugger. (The
debugger in this case refers to the system-level debugger, XDELTA.)
Note
IPC commands are intended to be used only for debugging and laboratory
implementation. Use of the commands might cause unexpected results.
Managing Storage Media 9–77