HP WebQoS Peak for HP-UX Concepts and Operation Guide

62 Chapter6

Conﬁguring HP LocalDirector Controller

What is HP LocalDirector Controller?

HP LocalDirector Controller (HP LDC) works with Cisco LocalDirector by

automatically generating the information needed by Cisco LocalDirector

to load balance TCP/IP trafﬁc across multiple servers. HP LDC,

speciﬁcally the HP LocalDirector Control daemon (ldc_agt), must be

conﬁgured and running on each system that is managed by Cisco

LocalDirector. Information regarding CiscoLocalDirector can be found at

the URL

http://www.cisco.com/warp/public/cc/cisco/mkt/scale/locald/index.shtml.

Figure 6-1 HP LocalDirector Controller

The information generated by HP LDC is referred to as “weights” in this

document. The weights help Cisco LocalDirector determine which

system has the resources to process an incoming request.

Initial weights are generatedby the Webstone benchmark tool. Webstone

generates trafﬁc to a system and calculates the throughput based on

getting different-sized static pages in three minutes. The throughput is

used to calculate the initial weights.

HP LDC adjusts the weights depending on CPU usage and system load.

Both the CPU usage and system load (measured by a one minute average

job queue) must reach their conﬁgured thresholds before the weights are

lowered. The weights will range between one and the initial weights.

Cisco

LocalDirector

HP LDC

Server 1

HP LDC

Server 2

Internet/

Intranet

HP 9000