Issuing an SNMP MIB query

Issue a MIB query to retrieve MIB variables from network devices and subsequently diagnose problems on those devices.

To perform this procedure, you must be in the SNMP MIB Browser.

  1. Navigate to the part of the MIB tree that contains the MIB object that you wish to query and select the desired MIB object. Specify the MIB object that you wish to query. You can do this in one of the following ways:
    The OID field displays the MIB object identifier that corresponds to the MIB object you selected.
    Tip: Standard MIB variables can be found at the MIB tree path iso/org/dod/internet/mgmt/mib-2. Vendor-specific MIB variables can be found at the MIB tree path iso/org/dod/internet/private/enterprises.
  2. Type the IP address or hostname of the target device in the Host field.
    If you launched the SNMP MIB Browser from the Event Viewer, from a network map, or from the Structure Browser, then the Host field is automatically filled in when the SNMP MIB Browser starts.
  3. Select the query to issue from the Method drop-down list.
    The options available within this menu are:
    Get
    Use this query to obtain a single (scalar) values; for example, sysUpTime
    Get Next
    Use this query to obtain the next single (scalar) value in an array.
    Walk
    Use this query to obtain array data; for example, system.
    Get Table
    Use this query to obtain table data.
    Graph
    Use this query to start the Graph Properties window and specify the information (content and scope) to be displayed in the MIB graph.

    The choice of SNMP query is constrained by the type of MIB object you selected.

    V4.2 Fix Pack 15:Some SNMP object labels refer to more than one OID and are thus not unique. The way that the GUI processes ambiguous labels is determined by the mib_browser.duplicate.mib.label.action property in the mib_browser.properties file. This property has the following allowed values:
    • always: Always use the OID instead of the label.
    • never: Always use the label. This was the behaviour prior to Fix Pack 15.
    • prompt: If the label is unique, use the label. If the label is not unique, you can choose to replace it with the OID, if the OID is known, choose from a list of multiple OIDs with that label, or use the label. This option is the default.
    For example, you cannot perform a Get query on a MIB variable of type table. If you try to issue a query on a node that does not accept that query, the SNMP MIB Browser responds with a warning.
  4. Deselect the Ignore filtering checkbox if you want to limit the interfaces that the SNMP MIB Browser queries by applying any interface filters that are configured. By default, the Ignore filtering option is selected, and the SNMP MIB Browser has access to all interfaces, regardless of any interface filters. Interface filters only apply to SNMP walks and SNMP table requests. The Ignore filtering checkbox is only active when the Walk or Get Table option is selected in the Method list.
  5. Click Go.
    The results of the query appear in the SNMP Query Results area.
    Note: If the SNMP query yields no results, the reason may be one of the following:
    • The MIB object you selected does not exist on the host.
    • The SNMP Helper, the device that the SNMP MIB Browser uses to query the host, is unable to access the host.
  6. To refresh MIB object data to see how data has changed since the last time a query was issued, click the Go button.