Interoperability Between L4 / L7 Virtual Services; Api For Agent Based Adaptive Balancing; O. Appendix I - KEMP Technologies LoadMaster 1500 Installation And Configuration Manual

5. Interoperability between L4 / L7 Virtual Services

When one switches a service from one persistency method to another, the absolute values of all VS / RS
counters will be reset to zero.
This may cause peaks in the service graphs when displaying relative values (bytes per second, etc.) when e.g.
the bytes counter jumps from terabyte values to zero.

O. Appendix I

1. API for Agent Based Adaptive Balancing

For adaptive scheduling the balancer periodically checks the system load on all the servers in the farm. Each
server machine has to provide a file that contains a numeric value in the range between 0 and 100
representing the actual load on this server (0 = idle, 100 = overload). The balancer retrieves this file by an
HTTP GET operation. It is the servers' job to provide the actual load in the ASCII file. There are no
prerequisites, though, how the servers evaluate this information.
Anyway there are some conditions that must hold:
There must exist an ASCII file with a number between 0 and 100 in the first line.
The file must be accessible to an HTTP GET from the balancer.
The URL must be the same on all servers.
The URL must match the entry "URL for adaptive scheduling" as set in the "Global Options" window.
The following is an example script to determine and present the load information on a
LINUX server:
Here is an example of a C program to determine and present the load information on a MS Windows NT or
2000 server:
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