A. Request for bestlinux.cs.twsu.edu.
ENTERING LOAD BALANCING SECTION List of servers for bestlinux 0: sisko.cs.twsu.edu 1: kira.cs.twsu.edu Return/Total : 1/2 Return/Total : 2/2 sisko.cs.twsu.edu 4735 kira.cs.twsu.edu 3580 BestPosition/BestHost : 1/kira.cs.twsu.edu LEAVING LOAD BALANCING SECTIONHere, kira.cs.twsu.edu has a lesser rating than sisko.cs.twsu.edu, so kira.cs.twsu.edu is returned as the best server to the client.
B. Request for www2.cs.twsu.edu with one of the servers having an optimal rating.
ENTERING LOAD BALANCING SECTION List of servers for www2 0: q.cs.twsu.edu 1: daneel.cs.twsu.edu 2: giskard.cs.twsu.edu 3: sisko.cs.twsu.edu 4: kira.cs.twsu.edu Received Best Rating daneel.cs.twsu.edu 400 BestPosition/BestHost : 1/daneel.cs.twsu.edu LEAVING LOAD BALANCING SECTIONHere, daneel.cs.twsu.edu has a rating less than the optimal rating of 1500, so dlbDNS returns back daneel.cs.twsu.edu as the best server to the client without waiting for the other servers to return their ratings.
C. Request for www1.cs.twsu.edu with only two of the four servers responding.
ENTERING LOAD BALANCING SECTION List of servers for www1 0: sisko.cs.twsu.edu 1: kira.cs.twsu.edu 2: daneel.cs.twsu.edu 3: giskard.cs.twsu.edu Return/Total : 2/4 Return/Total : 2/4 Return/Total : 2/4 Return/Total : 2/4 Return/Total : 2/4 *** Time elapsed for waiting *** sisko.cs.twsu.edu 4774 kira.cs.twsu.edu 3610 daneel.cs.twsu.edu 10000 giskard.cs.twsu.edu 10000 BestPosition/BestHost : 1/kira.cs.twsu.edu LEAVING LOAD BALANCING SECTIONThe dlbDNS waits a specific period of time for the servers to return their rating. If the servers fail to return in this time period, dlbDNS gives the server a maximum rating of 10000. Here, daneel.cs.twsu.edu and giskard.cs.twsu.edu fail to respond within the specific time period, so dlbDNS assigns them a maximum rating of 10000.
Request from dlbDNS Rating returned to dlbDNS : 4762 Sun Dec 13 17:34:58 CST 1998 Updated Rating : 4735 Request from dlbDNS Rating returned to dlbDNS : 4735 Request from dlbDNS Rating returned to dlbDNS : 4735 Sun Dec 13 17:35:58 CST 1998 Updated Rating : 4795 Sun Dec 13 17:36:58 CST 1998 Updated Rating : 4774 Request from dlbDNS Rating returned to dlbDNS : 4774 Request from dlbDNS Rating returned to dlbDNS : 4774 Sun Dec 13 17:37:58 CST 1998 Updated Rating : 4771 Sun Dec 13 17:38:58 CST 1998 Updated Rating : 4653 Sun Dec 13 17:39:59 CST 1998 Updated Rating : 4629 Sun Dec 13 17:40:59 CST 1998 Updated Rating : 4691 Sun Dec 13 17:41:59 CST 1998Here, the rating demon updates its rating once every minute independent of dlbDNS request. When there is a request for rating from dlbDNS, the rating demon replies by returning the latest rating of the server rather than calculating the rating again.
