Information
Global Server Load Balancing (GSLB) describes a range of technologies to distribute resources around the internet for various purposes. Depending on the user and nature of deployment, different goals are targeted, which include:
Disaster Recovery- Providing an alternate location for accessing a resource in the event of a failure, or to provide a means of shifting traffic easily to simplify maintenance (or both).
Load Sharing——分配多个位置之间的交通:
To minimize bandwidth costs.
Limit the capacity used at a given location.
Limit exposure to various issues, including outages, geographic disruption, and so on.
Performance-To position content closer to users, which enhances the users' experience.
Legal Obligations- Present users with different versions of resources based on political location.
Over time, various techniques have been developed to meet these requirements, although three techniques have withstood the test of time:
DNS based redirection to different locations;
Content level redirection to different locations, using HTTP redirection;
Route Injection to advertise the same IP address to multiple locations.
Route health injection or RHI, generally uses different methods more applicable to large companies than the first two, and is not covered in this guide. The other two techniques, that of DNS and content level redirection, are covered, with examples and various configurations.
The attached guide covers the basics of DNS and GSLB configuration that are necessary when deploying GSLB on the Citrix NetScaler Application Delivery Appliance. While the basics of the commands used for configuring GSLB are detailed in this guide, additional information on each command and a complete set of options can be found in the Citrix NetScaler Command Reference Guide, and additional details on various configurations are also found in the Traffic Management Guide.