The Drive Space module collects disk space usage data, including drive name, type, label, capacity, free space, percent free, and file system.

Discussion

One of the biggest issues DBAs have is with disk management, aka “disk free space monitoring”. This makes sense: we as DBAs aren’t usually in control of ordering or parceling out disk space, but the systems we’re in charge of typically take up more space than anything else in the company.

So, we have a great storm brewing:

• Database and backup files take up a ton of space
• DBAs usually don’t manage disk space allocation, and must request space
• There is no automatic space monitor/alert/management that comes installed with the OS, or with SQL Server

We’re absolutely primed for disks to run out of space, bringing down databases or ruining backup solutions. The best solution must have a few key features, and of course Minion Enterprise does:

• Collect disk space usage data into SQL Server tables in a central location.
• Use that data to project when the disk is likely to become full (or better still, 80% or 90% full).
• Automatically alert the DBA team. 
• Provide disk-specific configuration. After all, not all disks should be alerted on at 10% free space.
• Allow for disk alert exceptions (for disks that should never be alerted on).
• Allow for disk alert deferrals (for those times when the new SAN is already on the way and there's nothing else to do).

Tables

Collector.DriveSpace

Holds drive space data collected from servers.  Drive space alerts depend on the information in this table.

dbo.DriveSpaceReport

Alert.DriveSpaceDefer

This table holds drive space deferrment orders. Insert a row here to prevent ME from sending drive space alerts for a particular drive, for a set period of time.

Views

Collector.DriveSpaceCurrent

Provides the most recent collection of drive space data.

Each “Current” view associated with a Collector table contains all (or nearly all) of the columns from the base table, plus a “ViewDesc” description column, and columns from dbo.Servers data:

• ServerName
• ServiceLevel
• Version
• Edition
• Descr

Collector.DriveSpacePrevious

Provides the next-to-most recent collection of drive space data.

Each “Previous” view associated with a Collector table contains all (or nearly all) of the columns from the base table, plus a “ViewDesc” description column, and columns from dbo.Servers data:

• ServerName
• ServiceLevel
• Version
• Edition
• Descr

Stored Procedures

Collector.spDriveSpaceInsert

The script calls this procedure to perform the insert into the Collector.DriveSpace table.

Important: This procedure is meant to be used by automated collectors; we recommend against using it manually. Therefore, the parameter set is only documented internally.

Setup.DriveSpaceDefer

Allows you to set up a drive space deferment for a specific drive, for a set period of time. This allows you to keep the alerting system in place, but prevent alerts for situations that are under control.

For example, if Server1 drive D: has 2GB space left, but the drive is scheduled to be expanded over the weekend, you can defer alerts for Server1 drive D: until Monday.

Setup.DriveSpaceException

Jobs

CollectorDriveSpace-GOLD

CollectorDriveSpace-SILVER

CollectorDriveSpace-BRONZE

Executables

DriveSpace.exe

• $Query – This parameter refers to the service level that the collector should operate on. Examples: Gold, Silver, Bronze. For more information on this topic, see the article “Executables and Service Levels”.

Examples

Examples: Set up deferments, exceptions, and thresholds

Drive Space is a particularly flexible module, in that you can set your own drive-level alert deferments, drive-level alerting exceptions, server-level alert thresholds, and even drive-level thresholds.
Drive level alert deferment:
On Svr1, the E:\ drive is slowly filling up. Today it hit the threshold configured or the server – 5GB space free – and sent you an alert. You did your due diligence and determined that the E:\ drive really needs more space, and so you put in your request. Since you know about the issue, and now have to wait a week for the disk team to fulfil your request, you can defer further alerts about that drive for the next seven days. You shouldn’t keep getting the alert if the situation is under control!

Insert a row to the Alert.DriveSpaceDefer table, using the Setup.DriveSpaceDefer procedure, for Svr1 drive E:\, that ends 7 days from now:

EXEC Setup.DriveSpaceDefer @ServerName = 'Svr1',
    @DriveLetter = 'E:\',
    @DeferDate = '2016-02-23',
    @DeferEndDate = '2016-03-01',
    @DeferEndTime = '08:00:00';

 
Alert deferments can be extremely powerful. For example, you may want to turn off all alerts for C:\ drives across all “Bronze” level servers.  One simple insert statement will do this for you:

INSERT INTO Alert.DiskSpaceDefer (InstanceID
     , DriveLetter
     , Caption
     , DeferDate
     , DeferEndDate
     , DeferEndTime )
SELECT  InstanceID
      , 'C:\' AS DriveLetter
      , 'C:\' AS Caption
      , '01/01/2015' AS DeferDate
      , '12/31/2100' AS DeferEndDate
      , '00:00:00' DeferEndTime
FROM    dbo.Servers
WHERE   ServiceLevel = 'Bronze';

 
You could just as easily defer alerts in this way by environment, by SQL Server version or Windows version, or in any other way you can image. The data is there.

Drive level alerting exception:
Let’s say that there’s a drive you never, ever want to receive an alert on (in our case, drive D:\ on Svr10, which has InstanceID 10). Perhaps it’s someone else’s responsibility; perhaps there are no, and never will be, any SQL files on that drive. For whatever reason, you just don’t want to hear about it. In that case, insert a row to the dbo.DriveSpaceReport table:

INSERT INTO dbo.DriveSpaceReport
        ( InstanceID , Drive , AlertMethod, AlertValue, Report, IsActive, Comment)
-- Svr10: 
VALUES  ( 10 , 'D:\'  , 'GB'  , 5, 0, 1, 'Never alert on D: for this server.' );

 
Now, you will never be alerted on the Svr10 D:\ drive.
While the threshold was set to 5GB, it was only done for continuity purposes in case reporting ever gets turned back on the values aren't NULL.  The import part here is that Report is set to 0.

Server-level threshods:
You can set the drive space alert threshold at the server level using the dbo.DriveSpaceThresholdServer table (which makes this a sort of “server level default” for drive space thresholds, right?). What’s more, you can use one of a handful of alert methods: percent, GB, MB, or KB remaining on disk.

Let’s configure Svr1 to have a 10% threshold for alerts, and Svr2 to have a 5GB threshold:

INSERT INTO dbo.DriveSpaceReport
        ( InstanceID , Drive , AlertMethod, AlertValue, Report, IsActive, Comment)
-- Svr1:
VALUES  ( 10 , 'MinionDefault'  , 'Percent'  , 10, 1, 1, 'All drives for this server.' ),
-- Svr2:
VALUES  ( 17 , 'MinionDefault'  , 'GB'  , 5, 1, 1, 'All drives for this server.' );

Done!

Drive-level threshods:
Drive level thresholds are extremely similar to server level; they’re just drive-specific. If you have a server-level threshold, and a drive-level threshold, for the same server, then of course the drive-level threshold will apply for that drive; and the server level threshold will apply for all the other drives on the server.

Let’s configure Svr1’s Z:\ drive to have a 2GB threshold for alerts:
INSERT INTO dbo.DriveSpaceReport
        ( InstanceID , Drive , AlertMethod, AlertValue, Report, IsActive, Comment)
-- Svr1:
VALUES  ( 16 , 'Z:\'  , 'GB'  , 2, 1, 1, '2GB alert on Z: for this server.' );
Now, we will receive alerts when the Svr1 Z:\ drive is below 2 GB free space; and when any other drive on Svr1 is below 10% of its free space.

Global threshods:
One of the features that makes Minion Enterprise unique is its ability to be configured at a global level.  The system is installed with a single global threshold.  But you can define your own to perform some powerful things.  You can define individual drive thresholds at a global level.  Let's say that you want to never alert on a C: anywhere in your environment.  That's really easy to do.

INSERT INTO dbo.DriveSpaceReport
        ( InstanceID , Drive , AlertMethod, AlertValue, Report, IsActive, Comment)
-- Svr1:
VALUES  ( 0, 'C:\'  , 'GB'  , 2, 0, 1, 'Globally disable alerts for C:.' );
Now, you'll never see alerts for C: for any servers.

***It should be noted though that more-specific always beats less-specific.  So while the above global setting applies, it can be overridden by a server-specific setting.  This means that if there is a server that you do want to receive alerts on C: for, you can simply enter in a row for that server and it'll be excepted from the global setting.

 
https://minionware.desk.com/customer/portal/articles/2376684-drive-space-module
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