2-12DescriptionUse the rmon history command to add an entry to the history control table. If you do not specify theowner text keyword/argument combination, the owner of the entry is displayed as “null”.Use the undo rmon history command to remove an entry from the history control table.You can use the rmon history command to sample a specific port. You can also set the samplinginterval and the number of the samples that can be saved. After you execute this command, the RMONsystem samples the port periodically and stores the samples for later retrieval. The sampled informationincludes utilization, the number of errors, and total number of packets.You can use the display rmon history command to display the statistics of the history control table.Examples# Create the history control entry numbered 1 for Ethernet 1/0/1, with the table size being 10, thesampling interval being 5 seconds, and the owner being user1. system-viewSystem View: return to User View with Ctrl+Z.[Sysname]interface Ethernet 1/0/1[Sysname-Ethernet1/0/1]rmon history 1 buckets 10 interval 5 owner user1# Remove the history control entry numbered 15.[Sysname-Ethernet1/0/1] undo rmon history 15rmon prialarmSyntaxrmon prialarm entry-number prialarm-formula prialarm-des sampling-timer { delta | absolute |changeratio } rising_threshold threshold-value1 event-entry1 falling_threshold threshold-value2event-entry2 entrytype { forever | cycle cycle-period } [ owner text ]undo rmon prialarm entry-numberViewSystem viewParametersentry-number: Extended alarm entry index, in the range 1 to 65535.prialarm-formula: Expression used to perform operations on the alarm variables, a string of 1 to 256characters. The alarm variables in the expression must be represented by OIDs, for example,(.1.3.6.1.2.1.2.1.10.1)*8. The operations available are addition, subtraction, multiplication and divisionoperations. The operation results are rounded to values that are of long integer type. To prevent invalidoperation results, make sure the operation results of each step are valid long integers.prialarm-des: Alarm description, a string of 1 to 128 characters.sampling-timer: Sampling interval (in seconds), in the range 10 to 65535.delta | absolute | changeratio: Specifies the sample type.threshold-value1: Upper threshold, in the range 0 to 2147483647.event-entry1: Index of the event entry that corresponds to the rising threshold, in the range 0 to 65535.