Study Notes

When installed BA880 system with Zhu Feng yesterday, I saw the indeed load-balancing mechanism is DNS Round Robin. As the client requires for service, the DNS Round Robin give the client the first hostname/IP address in the local DNS zone recorders. For example, assume there’re totol 3 nodes in cluster, and related three DNS entries in the name table. The first accessing client would be given the first DNS address in the table, and the second client given the second, third accessing given the third. If there’s other clients, the fourth vistor, it is guided to login the first recorder as cycle-rotating.

DNS Round Robin has many disadvantages, such as TTL parameter(Time To Live), and caching recorders. In fact, Round Robin is loading distribution, not load balancing, for it does not know the load of every node. However, Round Robin mechanism has even been used by sina and yahoo for their distributed nodes around the country.

DHCP performance impact Kick-Start installation
I meet the trouble that when using KS file to install Linux, the ethernet network deviced (eth0) would not be sighed IP address by DHCP. And just repeat the KS install command(Linux ks=nfs:192.168.3.246:/os/1.cfg), it seemed to get dynamic IP again and go to install successfully. Note, if not repeat, configure the eth0 IP address manually would also go straightly. Perhaps I have to configure my own DHCP server for future experiments.