Description: A filter for selecting the rows of a MIB table that need to be sampled. This is meaningful only if the ahcfConfigObjectType is 'columnar'. A filter can be specified in terms of the values of identifier oids given in ahcfConfigIdentifierVariables. The format for this variable is ([Oid1 Value][,Oid2 Value][,Oid3 Value]) Oid1, Oid2 and Oid3 are the identifier oids specified in ahcfConfigIdentifierVariables. Value for a maximum of 3 identifier oids can be specified. A value of '()' is used as the default value for this variable and it will not be considered as a valid filter. For example, if the object being sampled is the disk space usage defined in the Host Resources MIB (RFC 1514) hrStorage.hrStorageTable.hrStorageEntry.hrStorageUsed, and the description of the storage medium (hrStorageDescr) is being used as the identifier oid. If there are three logical storage media ('/', '/usr' and '/var') and the user only wants to monitor the disk usage of media '/usr', then ahcfConfigFilterType can be set to 'inclusive' and ahcfConfigFilterSpec1 can be set to (/usr) If the user wants to monitor disk usage of all media other than '/', then ahcfConfigFilterType can be set to 'exclusive' and ahcfConfigFilterSpec1 can be set to (/) Maximum of three filters can be specified using ahcfConfigFilterSpec1, 2 and 3. The filter specs MUST be modifiable when the value of ahcfConfigStatus object is equal to active(1). The agent MUST re-evaluate the filters and retain the sample data for mib instances which were being sampled before and which pass the new filters also. For example, if the ahcfConfigFilterSpec1 was previously (/) and ahcfConfigFilterSpec2 is set to (/usr), then the agent MUST retain the previous sample data for the medium '/' and start collecting data for '/usr'. Note that if there are two identifier oids, the user can decide to provide the value for only Oid1 in the filters by leaving the value of Oid2 empty. That is (,)