History (RMON group 2)
By default all active ports generate two history control data entries per active Layer 2 Switch port or Layer 3 Switch interface. An active port is defined as one with a link up. If the link goes down the two entries are automatically deleted.
Two history entries are generated for each device:
The history data can be accessed and displayed using any of the popular RMON applications.
As shown in the following configuration
example, you can use the rmon history command to modify the
sampling interval, the buckets (number of entries saved before overwrite), and
owner
(RMON station that requests the information).
device# configure terminal device(config)# rmon history 1 interface 1 buckets 10 interval 10 owner nyc02
The show rmon history command can be used to display the history
control data, as shown in the following example.
device(config)# show rmon history 1 History 1 is active, owned by monitor Monitors interface mgmt1 (ifIndex 25) every 30 seconds 25 buckets were granted to store statistics