Alarm Configuration
in which they reside; for example, if you wish to set an alarm on an object located in an RMON Statistics table, you can determine the appropriate instance by noting the index number assigned to the table that is collecting data on the interface you’re interested in. In the case of the default tables, index numbers often mirror interface numbers; however, if there are multiple default tables per interface, or if additional tables have been created, this may not be true. (Table index numbers are assigned automatically as table entries are created; no two tables — even those on different interfaces — will share the same table index number.)
If you have selected an object from a table which is indexed by some other means — for example, by ring number — you must be sure to assign the instance accordingly. If you’re not sure how a tabular object is instanced, you can use the MIB Tools utility (described in the Tools Guide) to query the object; all available instances for the object will be displayed. (Host and matrix table objects — which are indexed by MAC address — require special handling; see the Note which follows this step, page
If you have selected an object which is not part of a table, you must assign an instance value of 0.
You can use the MIB Tree display to determine which objects are tabular and which are
TIP not: objects which are part of a table will descend from a blue folder (which will have a “T” on it, and a name which will almost always include the word “table”); objects which are not will descend directly from a yellow folder. (There may be one or more yellow folders in between the blue folder which contains the table and the leaf object you wish to use; however, those objects are still part of the table.)
Be sure you define your instance values carefully; if you neglect to set the instance correctly, you will receive the “Set failed; ensure variable is readable” error message when you click the Apply button to set your alarm.
Advanced Alarm Configuration |
