On a recent customer project there was the need to migrate off of VDA TLS encryption and migrate the connections from StoreFront to Citrix Gateway.
The customer previously had StoreFront direct connections and used the VDA TLS encryption setup to provide a TLS encrypted session to the desktop or applications.
The VDA TLS encryption setup was too much engineering labor for the day 2 day operations and therefore they asked for a alternate solution but still provide the client>desktop as an TLS encrypted session.
Here we have two options, the first is to use Citrix Gateway and StoreFront as authentication but this introduces the users with a new logon screen and then delegates the credentials with json to StoreFront.
The second is forcing the connections from StoreFront through the Citrix Gateway by the means of optimal gateway routing, and we don’t have any user experience changes because the logon point is still StoreFront.
Option two was chosen and after a quick and simple deployment a seamless migration with optimal gateway routing is in place.
First all the preparation in place is creating a new Citrix Gateway DNS record and a new StoreFront load-balancer IP into the current setup will be migrated, afterwards configure the CVAD wizard on the NetScaler for a simple Citrix Gateway deployment and unbind any authentication policies because these will not be used. Afterwards configure all the necessary settings for a standard Citrix Gateway deployment and propagate these changes across the cluster. When all this is done edit the web.config file of the store that got configured under the primary StoreFront servers IIS inetpub directory and search for: optimalGatewayForFarmsCollection and make sure there is an entry with optimalGatewayForFarms enabledOnDirectAccess=”true” and save the file. Propagate the changes and after that migrate the old DNS entry to the new StoreFront ip. You will see that after logon the desktop brokering is force through Citrix Gateway.
The following reference articles where used for configuration and testing:
How to Force Connections Through NetScaler Gateway Using Optimal Gateway Feature of StoreFront (citrix.com)
How to Configure Authentication at StoreFront using NetScaler Gateway – NetScaler Configuration (citrix.com)
FAQ: Configuring Authentication at StoreFront using NetScaler Gateway (citrix.com)
SSL configuration on VDA (citrix.com)
I’ve updated my lab environment with Citrix Gateway push OTP support and had some trouble in configuring the Citrix SSO app on my iPhone. For some reason it couldn’t setup the gateway connection and it wasn’t reachable. (Well that was my bad in checking all my devices but I’ll get to that)
Before the push OTP change I’ve worked with the authenticator app behavior and put in the code myself and this worked fine. The change to push OTP isn’t too difficult, and the following articles give you plenty of how-to information:
Keep in mind that if you have setup a previous OTP setup like I had the encryption part needs to be migrated otherwise it just won’t work. Registration cannot complete if you just flip it on and be done with it. Follow the migration part or just start fresh with OTP encryption enabled by default.
After I corrected the encryption problem I still could not register through the Citrix SSO app for push OTP functionality. It kept giving me the error gateway not reachable, fully checked everything in my environment was up and working. It kept me puzzling that it works fine with the previous authenticator method and if I re-registered it that way it would work (without the push of course because that functionality sits in the Citrix SSO app)
Finally after more troubleshooting I found the problem… because I’ve upgraded and integrated ADFS 2019 in my environment my content switching server and gateway etc. also needed to be SNI aware. Remember that everything worked fine on my Windows devices (even the Citrix SSO VPN functionality which I use quite often) but just not on my iPhone. Turning off SNI was the solution, it seems that the Citrix SSO app on iOS doesn’t support SNI.
Hope it helps!
Fun quick fact that I’ve encountered when deploying a ADC Gateway GSLB setup for a customer! You only have to enroll once with the nFactor/Native OTP on one of the ADC’s. (when having a Active Directory Domain across multiple datacenter sites)
The setup of choice:
- Two ADC appliances in HA set on each site
- GSLB enabled in active/passive mode for the Gateway across both sites
- Native OTP enabled and active as the way for authentication
- Active Directory Domain across two sites
There is no difference in configuration whatsoever because the magic of Native OTP depends on Active Directory.
Configure each ADC identically with the nFactor/Native OTP setup and enable GSLB and you’re done. I must admit at first I thought that I would need to enroll at both gateways independent but happily this is not the case.
For the configuration steps see common examples as below: