| For high
traffic sites desiring 100% up time, a hardware load balancer can be
used to precisely balance traffic between multiple servers. The
load balancer not only balances the traffic load, it also immediately
directs traffic away from a down server. There is no latency as with
global DNS. Advantages: Load
balancing is precise, not in how many visitors go to each server
but in how much load is put on each server. There is also
immediate failover protection.
Disadvantages: It is more
expensive since the load balancer is a relatively expensive piece of
equipment. Also, the load balancer creates a single point of
failure. If it goes down, no server is available within its
cluster. While it is unusual for a load balancer to go down, it
does happen.
Therefore, it is often recommended to have a hot backup load balancer.
|
Go to
Clustering page 3 |
