Citrix Systems 4.2 manual How Gslb Works in CloudPlatform

Models: 4.2

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Chapter 16. Managing Networks and Traffic

Load Balancing or Content Switching Virtual Servers: According to Citrix NetScaler terminology, a load balancing or content switching virtual server represents one or many servers on the local network. Clients send their requests to the load balancing or content switching virtual server’s virtual IP (VIP) address, and the virtual server balances the load across the local servers. After a GSLB virtual server selects a GSLB service representing either a local or a remote load balancing or content switching virtual server, the client sends the request to that virtual server’s VIP address.

DNS VIPs: DNS virtual IP represents a load balancing DNS virtual server on the GSLB service provider. The DNS requests for domains for which the GSLB service provider is authoritative can be sent to a DNS VIP.

Authoritative DNS: ADNS (Authoritative Domain Name Server) is a service that provides actual answer to DNS queries, such as web site IP address. In a GSLB environment, an ADNS service responds only to DNS requests for domains for which the GSLB service provider is authoritative. When an ADNS service is configured, the service provider owns that IP address and advertises it. When you create an ADNS service, the NetScaler responds to DNS queries on the configured ADNS service IP and port.

16.9.1.2. How GSLB Works in CloudPlatform

Global server load balancing is used to manage the traffic flow to a web site hosted on two separate zones that ideally are in different geographic locations. The following is an illustration of how GLSB functionality is provided in CloudPlatform: An organization, xyztelco, has set up a public cloud

that spans two zones, Zone-1 and Zone-2, across geographically separated data centers that are managed by CloudPlatform. Tenant-A of the cloud launches a highly available solution by using xyztelco cloud. For that purpose, they launch two instances each in both the zones: VM1 and VM2 in Zone-1 and VM5 and VM6 in Zone-2. Tenant-A acquires a public IP, IP-1 in Zone-1, and configures a load balancer rule to load balance the traffic between VM1 and VM2 instances. CloudPlatform orchestrates setting up a virtual server on the LB service provider in Zone-1. Virtual server 1 that is set up on the LB service provider in Zone-1 represents a publicly accessible virtual server that client reaches at IP-1. The client traffic to virtual server 1 at IP-1 will be load balanced across VM1 and VM2 instances.

Tenant-A acquires another public IP, IP-2 in Zone-2 and sets up a load balancer rule to load balance the traffic between VM5 and VM6 instances. Similarly in Zone-2, CloudPlatform orchestrates setting up a virtual server on the LB service provider. Virtual server 2 that is setup on the LB service provider in Zone-2 represents a publicly accessible virtual server that client reaches at IP-2. The client traffic that reaches virtual server 2 at IP-2 is load balanced across VM5 and VM6 instances. At this point Tenant-A has the service enabled in both the zones, but has no means to set up a disaster recovery plan if one of the zone fails. Additionally, there is no way for Tenant-A to load balance the traffic intelligently to one of the zones based on load, proximity and so on. The cloud administrator of xyztelco provisions a GSLB service provider to both the zones. A GSLB provider is typically an ADC that has the ability to act as an ADNS (Authoritative Domain Name Server) and has the mechanism to monitor health of virtual servers both at local and remote sites. The cloud admin enables GSLB as a service to the tenants that use zones 1 and 2.

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Citrix Systems 4.2 manual How Gslb Works in CloudPlatform

4.2 specifications

Citrix Systems, a leading provider of virtualization solutions and cloud computing technologies, released version 4.2 of its popular software, Citrix XenApp, which was previously known as Presentation Server. This version marked a significant evolution in providing users with remote access to applications and desktops, emphasizing simplicity, performance, and security.

One of the standout features of Citrix XenApp 4.2 is its improved application streaming capabilities. This technology allows applications to be delivered to users in real-time, reducing the need for extensive local installations and enhancing the user experience. With application streaming, administrators can efficiently manage applications on a central server while ensuring that users have immediate access to the necessary tools.

Another highlight of this version is the enhanced security measures put in place to protect sensitive data. Citrix XenApp 4.2 includes support for SSL encryption, providing a secure communication channel for data transmitted between the server and clients. This is particularly crucial for businesses that need to comply with strict data protection regulations. Additionally, the integration of endpoint security features ensures that unauthorized access to applications is minimized.

Performance enhancements are also a critical focus in this release. Citrix optimized the delivery of applications over various network conditions, ensuring that users experience minimal latency regardless of their location. This was achieved through the incorporation of SmartAccess and SmartControl technologies, which allow administrators to set policies based on user roles, device types, and network conditions. This level of granularity enables organization-wide security without compromising on usability.

The user experience was further improved with a revamped interface, making it easier for end-users to access their applications and data. Simplified menus, clear navigation paths, and the ability to customize user settings contributed to a more efficient workflow, allowing users to focus on their tasks rather than struggling with the software.

Finally, Citrix XenApp 4.2 was designed to be highly scalable. Organizations of all sizes could deploy this solution to deliver applications efficiently, adapting to their specific needs as their user base grows or changes. This flexibility is crucial for businesses looking to future-proof their IT investments while maintaining optimal performance.

In summary, Citrix XenApp 4.2 stands out with its enhanced application streaming, robust security features, improved performance under varying conditions, user-friendly interface, and scalability, making it an ideal choice for organizations seeking to leverage virtualization for remote access to applications and desktops.