Blog posts tagged with 'expertexchange'


31 Jul 2008 05:56 PM EDT

Load Balancing


A crucial piece of knowledge to being an Application Expert is providing availability and offload of the backend servers across any TCP port number. Most web applications run on port 80 and 443. Some enterprise applications use custom ports. Either way, if you want to optimize the performance and keep clients connected when one of the servers or applications starts to fail, you will need a Load Balancer such as the Citrix Application Switch.

Load balancing allows you to distribute incoming requests to a particular virtual server (vserver or VIP) evenly across several backend physical servers. This is also known as Server Load Balancing (SLB). The virtual server runs load balancing algorithms within the Citrix Application Switch.

A vserver consists of a combination of an IP address, port, and protocol that accepts incoming the traffic. The vserver is bound to a number of physical services running on physical servers in the backend server farm. Typical physical servers range from apache web servers to high-end enterprise applications such as SAP and Oracle.

The way it works is a client sends a request to the virtual server, which selects a physical server in the backend server farm and directs the request to the selected physical server. Load balancing allows the Citrix Application Switch to choose the physical server with the lowest load and greatest available resources and directs the incoming request to that server. The Citrix Application Switch can select from many different algorithms for balancing the load, the most common being Round Robin.

Different virtual servers can be configured for different sets of physical services, for example TCP and UDP services. The Citrix Load Balancer supports protocol/application specific vservers for HTTP, HTTPS, FTP, SSL, SSL BRIDGE, SSLTCP, NNTP, DNS, SIP and SNMP services.

To with with your understanding and first time configuration, this deployment guide speaks directly to configuring Load Balancing and SSL Offload on a Citrix Application Switch. It was developed for the SAP Application, but the concepts apply to any Web Application.

Citrix Load Balancing Deployment Guide.

Watch this Load Balancing Tip:


Tap into the power of AppExpert!

Read about the Citrix Load Balancer here.

Buy the Citrix Load Balancer here.

Expand Blog Post
11 Jun 2008 07:09 PM EDT

In the Application Expert series part 2, Caching, I released a Deployment Guide discussing Static and Dynamic Caching.  As we are partners with Microsoft, we recently did some work here internally setting up some Dynamic Caching for an ASP.NET application and thought we would share the knowledge. This Caching Deployment Guide for ASP.NET Web Applications discusses the way an Application Expert would find out the potential caching scenarios that a web application can benefit from, and shows how to create and test the NetScaler caching policies and settings to put these scenarios into effect.

Tap into the power of AppExpert!

Expand Blog Post
06 May 2008 12:08 PM EDT
[ Tags: apptips,  tips,  appexpert,  caching,  compression,  ssl offload,  load balancing,  content switching,  gslb,  global server load balancing,  ssl acceleration,  tcp multiplexing,  mpx,  netscaler,  acceleration,  delivery,  content,  rewrite,  expertexchange,  lb,  llb,  slb,  citrix load balancer,  citrix load balancing,  link load balancer,  link load balancing,  load balancer,  server load balancer,  server load balancing,  security load balancer,  security load balancing,  hardware load balancer,  hardware load balancing,  next gen load balancing,  website load balancer,  website load balancing,  application load balancer,  application load balancing,  application switch,  clustering,  web application controller,  application controller,  application delivery,  ssl multiplexing,  wan load balancing,  content rewrite,  client-ip,  x-forwarded-for,  apache,  iis,  external url,  internal url,  home page redirect,  apache rewrite,  server obfuscation,  application obfuscation,  http header,  policies,  policy,  policy engine,  pe,  cache,  appcache,  compress,  appcompress,  controller,  content switch,  content acceleration,  content accelerator,  application acceleration,  application accelerator,  tcp acceleration,  f5,  array,  zeus,  radware,  cisco,  microsoft,  asp,  ias,  foundry,  extreme,  sap,  oracle,  siebel,  peoplesoft,  bea,  googlejuice ]

As web applications grow in complexity, the art of accelerating them seems to remain the same. This art is performed by applying some basic concepts to the application; that is, Caching, Compression, Load Balancing, Global Server Load Balancing, SSL Offload & Acceleration, Content Switching, TCP Multiplexing and SSL Session Reuse.

Citrix® is a leader in Gartners magic quadrant for Application Delivery with their flagship appliance NetScaler®. NetScaler accelerates web application performance by leveraging multiple acceleration technologies and innovative TCP optimizations.

Whether you are building out a new datacenter and architecting it the right way, or retrofitting an existing datacenter, Citrix NetScaler will perform and keep costs down. Whether you are looking to accelerate legacy enterprise applications such as Oracle or SAP, or building a new web 2.0 social community, Citrix NetScaler contains all of the tools to get you there.

Citrix NetScaler web application delivery solutions are purpose built appliances that accelerate application performance, while simultaneously reducing datacenter costs and improving web application security. Platforms range from the entry level 7000 to the latest MPX-series appliances that provide an industry-leading 15 Gbs of throughput at Layers 4 through 7.

There's more here: Case Studies, White Papers, Analysts , Datasheets

Check out the new MPX!

Buy it here!

Tap into the power of AppExpert!

Expand Blog Post
29 Apr 2008 08:17 PM EDT
[ Tags: caching,  appexpert,  apptips,  tips,  netscaler,  expertexchange,  mpx,  cache,  appcache,  lb,  llb,  slb,  gslb,  citrix load balancer,  citrix load balancing,  link load balancer,  link load balancing,  load balancer,  load balancing,  server load balancer,  server load balancing,  security load balancer,  security load balancing,  hardware load balancer,  hardware load balancing,  next gen load balancing,  website load balancer,  website load balancing,  application load balancer,  application load balancing,  application switch,  clustering,  web application controller,  application controller,  application delivery,  tcp multiplexing,  ssl offload,  ssl multiplexing,  global server load balancing,  wan load balancing,  rewrite,  content rewrite,  client-ip,  x-forwarded-for,  apache,  iis,  external url,  internal url,  home page redirect,  apache rewrite,  server obfuscation,  application obfuscation,  http header,  policies,  policy,  policy engine,  pe,  compress,  compression,  appcompress,  controller,  content switching,  content switch,  acceleration,  content acceleration,  content accelerator,  application acceleration,  application accelerator,  tcp acceleration,  ssl acceleration,  f5,  array,  zeus,  radware,  cisco,  microsoft,  asp,  ias,  foundry,  extreme,  sap,  oracle,  siebel,  peoplesoft,  bea,  googlejuice ]
posted by Craig Ellrod

Becoming an Application Expert means that you can profile an application and quickly determine how it can be architected or re-constructed for higher performance. Of course, we want you to use the Citrix Application Switch as part of the architecture. In Part 1, we learned how to profile an application to learn what it looks like as the traffic flows through the Citrix Application Switch. Now we will determine what parts of an application are cacheable and what parts are non-cacheable.

By Application Profiling we can determine which parts of the application are cacheable and non-cacheable just by looking at the Request and Response headers. The application will sometimes tell you through it's "Cache-Control" header directives. Some content that we just know is static and doesn't ever change, we can consider cacheable as static content. Content that changes, such as reports, are often considered non-cacheable but with the help of Selectors and Dynamic Content Groups in the Citrix NetScaler, this content can be cached. As a proof of concept, we deployed the Citrix NetScaler Application Switch in the front of Oracle E-Business Suite v12 application and implemented caching policies for both static and dynamic content. As it turns out, alot of static content is cached by default policies and setting up dynamic policies is not that difficult. To see how, read the Caching Deployment Guide for Oracle E-Business Suite v12.

Watch this Caching Tip:

Tap into the power of AppExpert!

Expand Blog Post
04 Apr 2008 06:06 PM EDT
[ Tags: sap,  soa,  caching,  compression,  rewrite,  lb,  ssl offload,  soap,  xml,  wisl,  appexpert,  apptips,  tips,  netscaler,  llb,  slb,  gslb,  citrix load balancer,  citrix load balancing,  link load balancer,  link load balancing,  load balancer,  load balancing,  server load balancer,  server load balancing,  security load balancer,  security load balancing,  hardware load balancer,  hardware load balancing,  next gen load balancing,  website load balancer,  website load balancing,  application load balancer,  application load balancing,  application switch,  clustering,  web application controller,  application controller,  application delivery,  tcp multiplexing,  ssl multiplexing,  global server load balancing,  wan load balancing,  xml load balancer,  xml load balancing,  expertexchange,  mpx,  content rewrite,  client-ip,  x-forwarded-for,  apache,  iis,  external url,  internal url,  home page redirect,  apache rewrite,  server obfuscation,  application obfuscation,  http header,  headers,  policies,  policy,  policy engine,  pe,  request,  response,  cache,  appcache,  compress,  appcompress,  controller,  content switching,  content switch,  acceleration,  content acceleration,  content accelerator,  application acceleration,  application accelerator,  tcp acceleration,  ssl acceleration ]
posted by Craig Ellrod

The SAP Enterprise Service Oriented Architecture (SOA) provides a blueprint for services-based, enterprise scale business solutions that are adaptable, flexible, and open. Enterprise Services Architecture takes the concept of service-oriented architecture to a new level by transforming Web services into enterprise services. Bringing Citrix and SAP Enterprise Services Architecture together reduces the dependence on customized applications, and increases flexibility and reduces time to deployment while reducing operational expenses.


This Citrix / SAP Enterprise SOA Deployment Guide was created out of a joint engagement between Citrix and SAP at the Co-Innovation Laboratory in Palo Alto, California, USA. This deployment guide walks through the step-by-step configuration details of how to configure the Citrix NetScaler for use as front-end to SAP Portal for end-user traffic, that is HTTP ~ HTML. To further complement the value of the Enterprise SOA, this guide walks through the details of how to configure the Citrix NetScaler for use as a front-end to the SAP Composite Application Framework and SAP ERP Web Services platforms, providing a flexible load balancer and HTTPS encryption point for machine to machine web service traffic. With this deployment Citrix becomes an integral and flexible part of the SAP Enterprise SOA "Applistructure" bringing together applications and technology for a fast, flexible and highly effective service oriented IT infrastructure.


Watch this Load Balancing Tip:



Tap into the power of AppExpert

Expand Blog Post