abcWelcome to the continuing series on the ABC's of Networking.  For Today's letter  of "D", I picked a core component in the scaling of websites and application servers.  Today's word is a load balancing method that deals with dynamically changing application servers.

"D" is for Dynamic Ratio Load Balancing

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Dynamic Ratio Load Balancing

Pronounced:
   Dahy-nam-ik Rey-shoh Lohd Bal-uhns-ing

The ratio method of load balancing distributes connections across an array of servers in a server farm in proportion to the static ratio weights assigned to each individual server.  The Dynamic Ratio mode is like the Ratio method, except that ratio weights are based on continuous monitoring of the servers and are therefore continually changing.  The Dynamic Ratio method makes use of an agent on the server to report health metrics that are used to feed the dynamic ratio.