Not sure how efficient & advisable it is to link many servers.

Being conservative, I run a small sp as part of each nightly backup/maint plan on each SQL server I administer. It writes the free space into a small cummulative table in the Master db, which I can then retrieve with an external application every morning.

Table:

CREATE TABLE [dbo].[tblStatsDisk](

[ID] [int] IDENTITY(1,1) NOT NULL,

[DiskTimeStamp] [datetime] NULL,

[Drive] [char](1) NULL,

[FreeDisk] [bigint] NULL

Maint Plan SP:

USE MASTER

-- Description: Poll free disk space on each drive immediately after the backup

-- =============================================

ALTER PROCEDURE [dbo].[GetDiskFree]

AS

/* TEST HARNESS

exec [dbo].[GetDiskFree]

select * from dbo.tblStatsDisk

*/

BEGIN

SET NOCOUNT ON;

INSERT into dbo.tblStatsDisk (drive, FreeDisk)

EXEC master.dbo.xp_fixeddrives

-- this command creates the rows (one for each drive) with NULL date, srv... fields

-- the columns must allow NULL especially disktimestamp

UPDATE master.dbo.tblStatsDisk

SET DiskTimeStamp = (GETDATE())

where disktimestamp is null

END

----

How you collect and centralise this later is another story ... but you start small with a modular approach then build an application that combines this with some DB size stats collected from the backup DMV routines.

HTH