Citrix - 1.1.1 Introduction

This lesson covers application launch behaviour in XenApp and XenDesktop 7.6. Two features improve the perceived speed of Citrix sessions: session pre-launch and session lingering. Pre-launch establishes the user session in advance, before any application is requested. Lingering keeps the session open for a few minutes after the user closes their last application. A second click on an icon then reuses the existing session and the application appears almost instantly, giving users the impression of a local launch.

In XenApp 6.5 these behaviours were configured through Citrix policies. In 7.6 the configuration moves to the broker: it can be enabled per delivery group through the Studio console. The same screen also lets administrators allow anonymous access to applications, so users reach published apps through StoreFront kiosks without supplying credentials. Anonymous access is configured at the delivery group level by allowing unauthenticated or anonymous users; you then provide a StoreFront URL tuned for that audience.

Connection leasing

  • Each controller caches the connections to the applications and desktops users have used recently.
  • If the site database becomes unavailable, controllers switch to connection leasing mode.
  • Users can still launch their most-recent resources even when the central database is down.
  • Once the database is back, full operation resumes.

Connection leasing is a best practice promoted by Citrix to deliver high availability of published apps and desktops even during database outages. The feature is enabled automatically and works in the background: every controller keeps a copy of the connection metadata users need most often, so they keep working through transient database issues without noticing any disruption.

Summary

This introduction to Citrix explains how pre-launch sessions and session sharing work to optimize application startup speed and user experience. It covers authentication mechanisms (authenticated vs. anonymous access), configuration management through Citrix Broker, and the operational features like connection leasing and database caching that enable reliable user access to applications and desktops.

Key points

  • Pre-launch sessions and session sharing provide fast application startup with minimal overhead for end users
  • Authentication can be configured for authenticated users, anonymous/unauthenticated users, or via Kiosks depending on business requirements
  • Citrix Broker manages delivery group configuration, access policies, and anonymous credential handling for applications and desktops
  • Connection leasing enables users to reconnect to their most recently used applications and desktops even when databases are temporarily unavailable
  • Controllers cache user connections and session data during normal operation; when database connectivity is lost, the system switches to limited collection mode
  • Citrix management infrastructure has shifted from NGX to XenDesktop/XenApp with configuration now handled through Broker and access portals

FAQ

What is the main benefit of pre-launch sessions in Citrix?

Pre-launch sessions and session sharing provide fast application and desktop launch times with minimal overhead, giving users the perception of rapid application availability.

How does Citrix handle user access when the database is unavailable?

Controllers cache user connections and session data during normal operations. When the database becomes unavailable, the system switches to limited collection mode, allowing users to continue accessing their most recently used applications and desktops.

What authentication methods does Citrix support for application delivery?

Citrix supports authenticated users (with stored credentials), anonymous or unauthenticated users (requiring soft token/credential provider), and kiosk-based access (with credential requirements). Each method is configured through Citrix Broker when creating delivery groups.