Components

VDM has four main features.

An on-line report generator which creates reports directly from the INDEXF.SYS file; this makes it significantly faster than the DIRECTORY command when searching for files across an entire disk. Features include:

a report showing the 50 largest files on a disk

the ability to find files using a variety of selection criteria including size (used, allocated or unused), protection, organization (indexed, sequential, direct), etc.

V7 adds the ability to find files based on a file specification which can include wildcards (/file qualifier)

A report generator that creates reports from previously collected data. This data can be collected daily or weekly and from it reports can be generated:

showing total usage by user or UIC on a disk or group of disks

showing projected disk usage for capacity planning

V7 adds the ability to report usage by user across all disks that VDM collects data on (/sequence=detail)

A detached process that can be configured to send mail, send console messages and/or submit batch jobs when:

disks are filling past user defined thresholds

disks have experienced an error

a particular file has been changed

a particular file is found or has been deleted

a particular file has grown/shrunk beyond a specified size

GO; a utility that works much like set default but is more flexible. Go allows the user to change their DCL prompt automatically to reflect their current working directory, omit the square brackets from directory specifications and go back to your last working directory automatically.

Getting Started

This chapter shows you how to get started after you have installed VDM.

From the command line interface you can initiate data collection and generate reports. Some reports require that data collection has run; others can be run immediately. For further information on commands, refer to the chapter "VDM Commands". Here are some examples of DCL commands:

To show the directory structure on a disk drive, type:

$ VDM /REPORT=TREE /DISK=disk-name

To display which version of VDM you are running, type:

$ VDM /VERSION

Here is a procedure to generate sample reports from the DCL interface.

1. Enable the VDM command verb if necessary.

$ SET COMMAND VDM_CDU:VDM_COMMANDS

2. Specify a report; in this case a size report for all files with 5000 or more blocks of disk space allocated

$ VDM /REPORT=SIZE /DISK=disk /ALLOCATED=5000: /OUTPUT

3. Print the report.

$ PRINT VDM.LIS

Data Collection
To generate usage analysis or capacity projections, you must first run data collection.
We recommend you do the following to get started:
Run ANALYZE/DISK/REPAIR on your drives
If you haven't run the OpenVMS ANALYZE/DISK utility on your drives within the last two weeks, please run it before you run data collection. If it finds errors in your disk structure you may wish to run it again with the /REPAIR option. This will clean up any errors in file headers and pointers and prevent problems during data collection runs.

Review the data collection procedure
The directory [VDM.COM] contains the data collection procedure COLLECT.COM. It reads the DISKNAMES.DAT file and does the data collection on the specified drives. You may want to confirm that this file exists and contains an appropriate list of disk drives. If this file does not exist it should be created using the VDM_COM:CREATE_DISK_FILE.COM procedure. The only modification that you may want to make to the data collection procedure would be to remove collection for directories if it is unlikely that you will generate current usage or capacity reports summarized by directory. Some sites like to modify this file to collect data only 1 or 2 days a week; this is particularly appropriate at sites where large changes in disk usage are not likely to occur from day to day or that have a large number of disks and wish to avoid the overhead of collecting data on these disks every day. To change the time, frequency or queue with which collect.com is run edit the procedure vdm_com:resubmit.com.

Submit the data collection procedure to batch
Because the data collection procedure imposes a load on the system, we do not recommend that data collection be done on_line. Submit it to batch queue that will run at a lower priority or, even better, submit it to run at night during a low usage period.

Wait until the data collection procedure runs
Check the batch log to verify that the procedure executed correctly. It can be found in the default login directory of the account the batch procedure was submitted from. Once the data collection procedure has been executed, it will automatically be requeued to SYS$BATCH to run at a future date _ you can specify the date by modifying the resubmit.com command file. The log file will be in the VDM_DAT directory.

Generate an analysis report
The directory [VDM.COM] contains three sample data analysis procedures, ANALYSIS_1.COM, ANALYSIS_2.COM and ANALYSIS_3.COM. Look at them, select the one that is closest to your needs and customize it. You can run the data analysis procedures interactively.

Update the collection procedure
When you've established which drives you want to monitor, you can modify the DISKNAMES.DAT file to your needs or run the vdm_com:create_disk_file.com procedure to recreate this file at anytime.