Citrix Xenapp Logon Process Through Web Interface

This can be sort of confusing when logging in through a web interface that is configured to “Authenticate at the Web Interface”. First of all, that’s not what that setting means — When it’s clicked, it actually means that you’ll be authenticated at the XML broker. Whether you are troubleshooting slow logins, or just trying to configure the optimal architecture for faster logins — Knowing the Citrix logon process can be helpful. Here is the process flow as we see it, and how it works:

1). Enter credentials at the Web Interface
2). Web interface reaches out to the XML broker, and passes the credentials
3). XML broker reaches out to AD Domain Controller, and authenticated credentials.
4). After being authenticated, user can request an ICA file for application launch
5). The best server will be selected based on load evaluators
6). Best server will respond back to the web interface with ICA file
7). ICA file is passed from Web Interface to client machine
8). Client machine is connected over ICA to given Xenapp server
9). Xenapp server confirms the RDS/TS License is in order
10). AD is queried for roaming profile information
11). Roaming profile is downloaded to the Xenapp server
12). Xenapp server checks with Citrix license server to make sure licensing is in order
13). Microsoft GPO’s get applied
14). Citrix policies get applied
15). User’s “Startup” folder gets executed, launching logon scripts, etc
13). Application / Desktop launches.