====== MS-SQL Free space in file ======

===== Purpose =====
  * The disk space allocated to a data file is logically divided into pages and extents 
  * Being able to monitor database files free space evolution becomes then important to stablish a good database storage strategy.  

**Monitor features include :**
  * Monitoring of every SQL Server file type (Data - row -, Log ...) and specific file name 
  * Able to alert if free space in a file  (of any type) has reached a given threshold expressed in MB or percentage

===== Configuration hints =====

**Surveillance table:**\\
  * This is a table of rules that you can use to configure and customize the configuration.
  * Each line of the table will define a rule of monitoring. You can combine multiple rules to cover different cases. 
  * Within a rule, you can configure the **SQL Server file type** you want to monitor, **specific file name(s)** using regular expressions, a **free space in file threshold** expressed in MB or percentage

**File type**\\
Select the specific SQL server file type you want to monitor , select "Any" to monitor free space in any kind of file, select "Aggregate if you need to monitor the total free space in all database files 

**File name:**\\
You can set a file specific rule by setting its name in the File name filter field. Use * to match any file name, or use regular expressions.

**Free space in file:**\\
Use the multi-threshold syntax to set multiple threshold/severity associations: G2W:40 W2M:30 M2C:5 (Green To Warning, Warning To Major, etc...), expressed in MB or percentage  An alarm of the corresponding severity will be sent if free space in file is **lower** than threshold.  Set 0 in the field if unused
 
Notice that values retrieved in MB will be rounded 
===== Surveillance table =====
^Parameter^Description^
^Active|Use this field to activate or deactivate a line of configuration.|
^File type|Select the specific SQL Server type file you want to monitor Select "Any" so to monitor every type of file Select "Aggregate" if you want to monitor the free space of all database files (aggregated)|
^File name|A filter to match only a specific SQL Server file name, you can use regular expression, white or black list|
^Free space in file|The threshold for the free space in file You can use the multi threshold syntax (i.e. : G2W:40 W2C:5) . Values can be expressed in MB or Percentage|
^Unit|Represents  the free space in file unit of measure|
^Auto clear|If checked, the alarm will be cleared as soon as the alarm condition is not met anymore.|
^Alarm tag|This field allows to add custom text within the alarm message. %MSG% variable will contain the actual generated message and can be used such as: "my_prefix %MSG% my_suffix". By default, tag will be used as prefix.|
^Alarm|If checked, this line of surveillance will be used for alarm generation.|
^Metric|If checked, this line of surveillance will be used for metric generation.|
^Report|If checked, this line of surveillance will used for showing threshold and severity in the daily report|
===== Examples =====
 
^Active^File type^File name^Free space in file^Unit^Auto clear^Alarm tag^Alarm^Metric^Report^
|true|Data|DBDATA|G2W:30 W2C:5|Percentage|true| |true|true|true|

**Effect** : For this rule, only Data - rows - type files  will be monitored (File Type set to : "Data").
 
All Data type files containing the string "DBDATA" on their file names will be taken into account.  
A WARNING alarm is sent if free space in file is 30% or less, a CRITICAL alarm if 5% or less.
===== Generated metrics =====
^metricId^metricUnit^metricTarget^metricDescription^
|MSSQL_DATABASE_FREE_SPACE_IN_FILE_PERCENT|Percentage|[File type] - [File name]|Retrieved SQL Server file free space,  expressed in percentage|
|MSSQL_DATABASE_FREE_SPACE_IN_FILE_MB|MB|[File type] - [File name]|Retrieved SQL Server file free space,  expressed in MB|
|MSSQL_DATABASE_AGG_FREE_SPACE_IN_FILE_PERCENT|Percentage|AGGREGATE|The addition of all retrieved SQL Server files free spaces - aggregated - of a given database, expressed in percentage|
|MSSQL_DATABASE_AGG_FREE_SPACE_IN_FILE_MB|MB|AGGREGATE|The addition of all retrieved SQL Server files free spaces - aggregated - of a given database, expressed in MB|