Creating a Custom Vendor Certification › Understanding the Vendor Certification XML Structure › ExpressionGroup

ExpressionGroup

The ExpressionGroup maps attributes as follows:

• From the AttributeGroup (that defines how to get a metric from an SNMP MIB)
• To the metrics specified in a metric family (that defines how an attribute is stored in the database)

You can store a MIB value in the database as it is received from the device or after some normalization operations are performed. For example, normalization operations include dividing or multiplying with 1024 to transform to/from kilobytes.

ExpressionGroup/name

(Optional) Specifies the expression group name.

Can be updated: Yes

Possible values: Plain text

Effect of updating: None

ExpressionGroup/destCert

Specifies the metric family that contains the destAttrs to populate.

Can be updated: Yes

Possible values: Any valid metric family

Effect of updating: Changes the permissible expression destAttr.

When does the update take effect: Immediately

Required actions for updates to take effect: None

ExpressionGroup/Filter

(Optional) Specifies which components are discovered. Using the Filter reduces the number of components that are managed.

Can be updated: Yes

Possible values: Boolean MVEL expression using available Attributes

Effect of updating: Changes which components are discovered.

When does the update take effect: After component rediscovery.

Required actions for updates to take effect: Update the metric family or change the vendor certification priority.