Using The Gslb Advanced Feature Set Option; Configuring Gslb - Cisco catalyst 6500 series Configuration Note

Chapter 8 Configuring Additional Features and Options

Using the GSLB Advanced Feature Set Option

To enable GSLB, perform this task in privileged mode:
Command
Router# config t
Router(config)# mod csm 5
Router(config-module-csm)# variable name value
Router(config-module-csm)# exit
Router (config)# write mem
Router#:hw-module slot number reset
1. GSLB requires a separately purchased license. To purchase your GSLB license, contact your Cisco representative.

Configuring GSLB

Global Server Load Balancing (GSLB) performs load balancing between multiple, dispersed hosting
sites by directing client connections through DNS to different server farms and real servers based on load
availability. GSLB is performed using access lists, maps, server farms, and load balancing algorithms.
Table 8-1
Table 8-1 GSLB Operations
Client Request (From)
Access lists can be used to
filter incoming DNS
requests, and policies are
used to associate the
configured maps,
client-groups, and server
farms for incoming DNS
requests.
Figure 8-1
OL-4612-01
gives an overview of what is required for a GSLB configuration on the CSM.
Domain (For)
A map is configured to specify
the domain names that client
requests must match. Regular
expression syntax is
supported.
For example, domain names
are cnn.com or yahoo.com that
a client request must be
matched against. If the domain
name matches the specified
map of a policy, the primary
server farm is queried for a
real server to respond to the
request.
shows a basic configuration for GSLB.
Purpose
Enters the configuration mode, and enters CSM
configuration mode for the specific CSM (for
example, module 5, as used here).
Enables GSLB by using the name and value
provided as follows:
1
Name=
Value=
Exits CSM module configuration mode, and save the
configuration changes.
Reboots your CSM to activate changes.
Server farm (To)
A server farm specifies a
group of real servers where
information is located that
satisfies the client's request.
Catalyst 6500 Series Content Switching Module Configuration Note
Configuring Global Server Load Balancing
Algorithm (Method)
The GSLB probe is available
for determining a target real
server's availability, using the
probe type configured on the
real server.
GSLB server farm predictors
are round-robin least load,
ordered list, hash address
source, hash domain, hash
domain address source.
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