The SNMP point manager view is the default view on Snmp Point Device Extension. It is used to compile and display the contents of MIB files for easy creation of SNMP proxy points that represent data values in the actual SNMP device (based on the information contained in the compiled MIB file). It is also used for viewing, storing, and removing SNMP trap and notification types learned for an SnmpDevice from the compiled MIB file.
The SNMP point manager view is basically the same as the standard point manager view that is used for most Niagara drivers and is described in detail in the NiagaraAX-3.x Drivers Guide.
The SNMP point manager view splits into two panes when you do a “Discover” (see Figure 22).
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Discover pane
This pane displays MIB entries from the last compiled MIB file.
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Database pane
This pane displays the points that are added to your station database.
In addition to the standard point manager functions, the SNMP point manager view has some SNMP-specific functions that are described in the following sections:
The discover pane displays MIB entries from the last compiled MIB file. These entries provide a template for creating and pre-configuring SNMP proxy points for the SnmpDevice (in particular, it automatically sets up such SNMP proxy point properties as the 'Object Identifier', or OID). The columns of the table include:
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Name
The name of the OBJECT-TYPE of the MIB entry. This name will be used to give a name to any created SNMP proxy points based on the entry.
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OID
The Object Identifier of the given entry. This OID will be pre-configured in the 'Object Identifier' property of any created SNMP proxy points based on the entry.
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Type
The type of object given in the SYNTAX section of the MIB entry. Common examples are INTEGER, DisplayString, Gauge, IpAddress, Counter, TimeTicks, etc. This type is used to pre-configure the 'Variable Type' property of any created writable SNMP proxy points based on the entry.
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Value
This column displays the point value. When the MIB is loaded but not “walked” the value column is empty.
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Access
The accessibility of the MIB entry (read-only, read-write, not-accessible). Used to determine if and what type (read-only or writable) of SNMP proxy points can be created for the given entry.
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Status
The current relevance of the MIB entry: mandatory, current, optional, deprecated, or obsolete. For display purposes only, does not affect creation of SNMP proxy points based on the entry.
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ElementType
This column is only used internally by Niagara during creation of SNMP proxy points based on selected entries in the table. It displays whether the MIB entry is a sequence element, trap-type, notification-type, or non-sequence element.
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Description
Displays a summary of the function of the given MIB entry.
The SNMP point manager Database pane is located below the Discover pane. This pane lists the proxy points that are currently in the database. You may edit some of the point values, depending on the value type, by double clicking on the desired row and using the Edit dialog box. The columns of the table include:
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Path
This column displays the ORD path, starting from the station database to the listed point.
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Name
This is the displayed point name.
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Type
This is the type of object given in the SYNTAX section of the MIB entry. Common examples are Integer, DisplayString, Gauge, IpAddress, Counter, TimeTicks, etc. This type is used to pre-configure the 'Variable Type' property of any created writable SNMP proxy points based on the entry.
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Out
This is the value of the point
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Object Identifier
The Object Identifier of the given point. This OID will be pre-configured in the 'Object Identifier' property of any created SNMP proxy points based on the entry.
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Variable Type
This is the variable type of the proxy point. You can edit the variable type for input values but cannot edit the variable type for output values.
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Enabled
This property allows you to set the proxy point in service (with a
truevalue) or to set it out of service (with afalsevalue). -
Device Facets
This property represents the device proxy point facets for how the value should be displayed in Niagara.
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Facets
This property represents the parent Niagara proxy point’s facets, for how the value should be displayed in Niagara.
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Conversion
This property specifies the conversion to use between the “read value” (in Device Facets) and the parent point facets, where “Default” is typically used.
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Read Value
(read only) This is the last value read from the device, expressed in device facets.
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Write Value
(read only) This is applies only if the point is writable. This is the last value written, using device facets.
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Tuning Policy Name
This property specifies the SNMP service type to use when binding to this item.
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Value
This column displays the point value. When the MIB is loaded but not “walked” the value column is empty.
The SNMP point discovery (or “learn”) process includes two steps:
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Loading the MIB
“Loading the MIB” is the process where the point manager compiles, reads, and displays points in the table pane of the SNMP point manager view. See Loading the MIB for details.
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Walking the MIB
“Walking the MIB is where communication takes place between an agent (client) application and a manager application to discover the point values for those loaded point types that have values available.
When you click the button, the SNMP point manager opens the Select MIBs to load dialog box.
The “MIB to load” field allows for specifying the MIB and populating the point table based on the MIB file that you select. When a MIB file is “loaded”, the MIB file and any dependent files are read into memory. The object types that are available for a device are limited to those types that are defined in the MIB file. Loading the MIB is a client-side operation that does not require remote communication. If you do not select the “Walk the MIB?” option, no data values are determined for point types that are defined in the MIB. This might be an option that you use when you are developing an application offline. After developing your application, you can “walk” the MIB when you can establish communication between the SNMP agent and manager applications.
The resulting table contains only MIB entries for the most recent MIB file to be compiled and loaded.
If there are errors when trying to compile the MIB files that you selected, an error message displays to indicate the errors encountered. For example, a missing dependent MIB file would cause an exception pop-up similar to the one shown in Figure 24
If no errors are encountered after issuing the LoadMIB command, the MIB entries contained in the loaded MIB file appear in the table (as shown in Figure 21 and Figure 22).
Dependent MIBs may be required by the primary MIB. Any MIBs that are not already available in the snmp module may be placed in one or more accessible folders.
The Dependent MIB Directories dialog box provides a way to specify MIB file locations that satisfy dependencies of the primary MIB file.
This dialog box displays when you select 
from the right corner of the button.
This is a time-saver if you have one or more locations where you store dependency MIBs. Once the folder locations are specified in this dialog box (as shown in Figure 25) they are loaded any time that a Load MIB type command is issued (for example, Load MIB and Walk MIB).
The Dependent MIBs list configuration is saved as a user option. Therefore, running Workbench from a different platform may
present you with a different list of MIB directories.
The Dependent MIB Directories dialog box allows you to add and remove MIB directories from a list, as described below:
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MIB directories to the list
Click the button to navigate to a directory to add to the list.
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MIB directories from the directories list
Use the button to remove any selected directories from the list.