# Creating a history using EDM

RMON can be used to collect statistics at intervals. For example, if switch performance is monitored over a weekend, enough buckets to cover two days must be set aside. To do this, set the history to gather one bucket each hour, thus covering a 48-hour period. After history characteristics are set, they cannot be modified; the history must be deleted and another created.

Use the following procedure to establish a history for a port, and set the bucket interval.

## Procedure steps

1. From the navigation tree, double-click Serviceability.

2. In the Serviceability tree, double-click RMON.

3. In the RMON tree, double-click Control.

4. In the work area, click the History tab.

5. In the toolbar, click Insert.

   The Insert History dialog box appears.

6. In the fields provided, enter the information for the new RMON history.

7. Click Insert.

## Variable Definitions

The following table describes the fields of the Insert History dialog box.

Field | Description
--- | ---
Index | Indicates a unique value assigned to each interface. An index identifies an entry in a table.
Port | Indicates any Ethernet interface on the device.
BucketsRequested | Indicates the requested number of discrete time intervals over which data is to be saved in the part of the media-specific table associated with this entry.
Interval | Indicates the interval in seconds over which the data is sampled for each bucket in the part of the media-specific table associated with this entry. You can set this interval to a number of seconds between 1 and 3600 (1 hour). Because the counters in a bucket may overflow at their maximum value with no indication, note the possibility of overflow in the associated counters. Consider the minimum time in which a counter could overflow on a particular media type and set the historyControlInterval object to a value less than this interval. This interval is typically most important for the octets counter in a media-specific table. For example, on an Ethernet network, the etherHistoryOctets counter could overflow in about one hour at the Ethernet's maximum utilization.
Owner | Indicates the network management system that created this entry.