Measure the test taker's knowledge about the historical control tasks of GE Ethernet switches.

To learn how to operate the historical control tasks of GE Ethernet switches, there are many problems with Ge Ethernet switches. For various models of Gigabit Ethernet switches, the following is a question and answer topic about historical control tasks. I hope to cover all questions about the use of Gigabit Ethernet switches by netizens.

History Group

The history Group periodically samples the statistical samples of one or more ports of a Gigabit Ethernet switch, obtains network information for each period of time, and saves these historical statistics. The MIB defined in RFC1757 are composed of two tables: The History control table. each row of the table defines a function to sample a specific port at a specific sampling interval.

The historical data table of the Gigabit Ethernet switch, which is used to record the sampled data. Each data table is collected and stored in a new row of the historical data table. The historical data table uses a bucket structure. When the number of rows of historical data that have been saved reaches the maximum value, the new data will overwrite the oldest row.

In specific implementation, the management site uses SNMP to set the required historical sampling function in the history control table. What the RMON agent does is to sample the statistical data according to the historical control table, save the result to the historical data table. Use the linked list of the following data structure as the historical parameter table to save information about each historical statistical task that has been defined.
Struct HISTORY-TEMP
Struct HISTORY-TEMP * next;
UNSIGNED history-indes;/* historical serial number */
UNSIGNED sample-indes;/* sequence number of the last sample */
Unigned buckets-requested;/* Number of row samples stored in the historical Request */
UNSIGNED time-start;/* record sampling interval start time second )*/
UNSIGNED octets;/* record the statistical data at the beginning of the sampling interval */
UNSIGNED pkts;
UNSIGNED broadcastpkts;
UNSIGNED multicastpkts;
UNSIGNED crcerror;
UNSIGNED undersizepkts;
UNSIGNED oversizepkts;
UNSIGNED fragment;
UNSIGNED jabbers;
UNSIGNED collisions;
UNSIGNED timer;/* timer used for this history */
};

A Gigabit Ethernet switch history group consists of two tasks: historical control tasks and Historical monitoring tasks. When the SNMP agent accepts the management site request to perform operations on the MIB, an event is generated, which activates the history control task. The history control task completes the following cyclic operations:

Obtain events. This operation is blocked if no event exists.

◆ Check whether a new history statistics task is added to the control table. If yes, you need to set and save parameters for the new historical statistics task and create a timer. The scheduled period is the value of HistoryControlInterval in the history control table. A message is sent to the Message Queue of the history group after the scheduled completion. The message value is the index value of the history group.

◆ Check whether historyXontrolBucketsRequested in the history of the Gigabit Ethernet switch defined in the history control table has been modified by the management site. If any, you need to adjust the bucket size.

◆ Check whether the historical statistics defined in the history control table are deleted by the management site. If a Gigabit Ethernet switch exists, delete the historical statistics in the following order: Delete the corresponding data rows in the historical data table, delete the timer, and delete the corresponding nodes in the parameter table.