Refresh
Snapshots can be taken either from the or from the tab and then stored to a file. A snapshot file contains the MIB object instances (values) that were in the or panel when the snapshot has been taken. A snapshot can be loaded from file at any time thereafter and displayed within a snapshot browser dialog. In addition, snapshots can be compared to identify differences between snapshots.
Snapshots can be used inter alia to:
Save the state of an agent or of a sub-tree of the same for future reference.
How-To: Browse the iso sub-tree of the agent and create a snapshot file from it. Then you can load and browse the snapshot (file) at any later time.
Save the state of an agent or of a sub-tree of the same to restore the values at a later time.
How-To: Browse the iso sub-tree of the agent and create a snapshot file from it. At a later time re-select the target agent's target and then load the snapshot (file). By using the function of the , the values can be set on the target agent.
Compare the state of two agents or of two states of the same agent at different points in time.
How-To: Browse the iso sub-tree of the agent and create a snapshot file from it for both agents or at two different points in time respectively. Then compare the two snapshot files by using the .
Copy the values of one agent or any sub-tree of its MIB to another agent.
How-To: Select the source agent as target and browse the iso sub-tree of that agent. Create a snapshot file from the panel. Then load select the target agent's target and open the snapshot. By using the function of the , the values can be set on the target agent.
To Create a Snapshot
1. Select the target from which you want to create the snapshot.
2. Select the sub-tree you want to create a snapshot from in the MIB tree. To create a snapshot from the complete MIB of an agent, select the iso node.
3. Either use or from the selected node's context menu to retrieve the instances in the selected sub-tree. Using is slower than if the sub-tree contains many instances. However, the first allows to retrieve several sub-trees one after the other so that the resulting snapshot contains the union set of the retrieved sub-trees.
4. Choose from Tree if you used Get to retrieve the values or from tab if you used . Select a file or specify a new file name and press to save the snapshot file.
To Open a Snapshot
1. Choose from the main menu and select the snapshot file to open.
2. Press to load and display the snapshot in a Snapshot Browser window.
To Compare Two Snapshots
1. Choose from the main menu.
2. The is displayed. It has three steps. The first two steps are required and specify the snapshots to be compared. The third (optional) step specifies which syntaxes should be compared and whether only values that are present in both snapshots should be compared.
A Snapshot Browser is divided into a toolbar and a tree-table area. The tree-table has four columns:
1. MIB Tree
The MIB tree column contains the MIB object identifiers of the MIB objects and instances in the snapshot. By default the MIB tree column display objects and instances as an expanded tree. By clicking on the button in the upper left corner of the table's header, the tree is flattened and the objects and instances in the snapshot are displayed as a table.
2. Syntax
If the MIB object in a row is an OBJECT-TYPE definition or instance, then its syntax is displayed in this column. The syntax of MIB OBJECT-TYPE definitions is displayed as defined in the corresponding MIB module, whereas the syntax of MIB object instances is displayed as received from the agent.
3. Value
The value of an object instance. The value is displayed by using the DISPLAY-HINT specification applicable for that object definition, if such a definition is available in the currently loaded set of MIB modules.
4. Status
The status column shows the operation status for or operations per value instance. The status values Restored and Refreshed indicate operation success, whereas Not Restored and Not Refreshed indicate that the restore or refresh operation did not succeed on the particular instance, because there was an error on another instance which has been sent in the same PDU. For restore operations, values are sent within the same PDU, when they are part of the same row. For refresh operations, up to the maximum number of variable bindings allowed per PDU are sent within one PDU. An error status is indicated by a lower letter starting error status description.
Refresh
Refresh the values in the snapshot from the current target. The target that will be used for any operations in a snapshot browser window is displayed in the window's title. While the refresh operation is performed, a progress bar is being displayed. After completion, a message box is shown and the status column contains detail information about the operation success for each value instance.
Save
Saves the content of the snapshot browser to a snapshot file. With this function snapshot files can be copied or kept up-to-date with the latest agent state (in conjunction with the operation).
Restore
The restore operation sends the values in the snapshot as SET requests to the current target (as displayed in the title). In other words, the restore operation assigns the values in the snapshot to the corresponding MIB object instances of the target agent. By pressing the button an option dialog is shown which allows to specify whether
Note: This option is only available from the Snapshot Comparison Browser.
only mismatched instances are restored;
rows with a RowStatus column should be set into notInService(2) before updating them or set to createAndWait(5) before creating them;
only those objects are restored whose OBJECT-TYPE definition (which has to be present in the loaded MIB modules) has a MAX-ACCESS value of read-write or read-create.
By pressing , the values that match the selected criteria are set in the target agent. Each scalar value will be set by itself, which means that each scalar variable binding instance is sent in its own PDU to the target. Columnar object instances (if the corresponding table definition is contained in the loaded MIB modules) will be sent row-by-row to the agent.
If the second option (use RowStatus states) is selected rows will be created in the target agent by setting the RowStatus column to createAndWait(5) and then sending a SET PDU with all matched values for that row. Then the status of the RowStatus column is set to active(1) or it is left unchanged if the status is not specified by the snapshot or it is specified as any other value than active(1).
Note: If the tool bar is part of the and the second option is active and the values restored do not contain a row that is contained in the opposite snapshot, then the row is deleted from the target by sending a SET request on the corresponding RowStatus column with a value of destroy(6).
During the restore operation a progress bar is shown. After completion, a message box is displayed and the status column contains detail information about the operation success for each value instance.
16.4 Snapshot Comparison Browser
The Snapshot Comparison Browser is similar to the described above, except that it contains a second tool bar for the second snapshot and the following three additional columns:
Difference
The column shows the comparison result for each value pair. Possible values are:
Equal Sign
The equal sign indicates that both values have been compared, have the same syntax, and that they equal each other.
Less Than (Yellow)
The yellow less-than-sign indicates that both values have the same syntax, have been compared, and the left value is less than the right value.
Greater Than (Yellow)
The yellow greater-than-sign indicates that both values have been compared, have the same syntax, and the left value is greater than the right value.
Less Than (Red)
The red less-than-sign indicates that only the right snapshot contains a value for this instance.
Greater Than (Red)
The red greater-than-sign indicates that only the left snapshot contains a value for this instance.
Error
The stop/error sign indicates that the values of the both snapshots have different syntax and therefore cannot be compared.
Right Syntax
The syntax of the right snapshot's value.
Right Value
The right snapshot's value.