Since Citrix introduced FlexCast Management Architecture (FMA) there has been some complications around the design of large XenApp/XenDesktop environments in companies than span multiple parts of the globe.
Conderations such as the sharing or seperation of Delivery Controllers, StoreFront servers, SQL servers exist. Also considerations such as Citrix policy placement, Delivery Group creation and Machine Catalog creation exist.
If you look at a Citrix Site from a high level it is made up of Delivery Controllers, StoreFront servers, VDAs and SQL servers. Some questions that need answered when designing a geographically spread Citrix solution may be:
- Do I place VDAs (Worker Machines) in multiple datacentres local to each geographical location?
- What will the latency be between Delivery Controllers and VDAs/SQL, where will I place my DDCs? Have I enough bandwidth to support the desired user experience?
- Do I create Delivery Groups for each location i.e. London desktops, Paris desktops or amalgamate them?
- How will I apply policies to my users? Keep consistency or is there a need to have different policies for each region?
- Will I just create seperate Citrix Sites local to each region so thay can have their own SQL servers and DDCs etc?
You may choose to create one Citrix Site i.e. London, and have all resources located in London datacentres however you need to ensure any remote offices have sufficient WAN links in to London. On the other hand you may choose to have multiple Citrix Sites for each location. This means having to manage seperate instances of XenApp/XenDesktop, multiple SQL, DDC and StoreFront servers bringing extra administrative overhead.
With XenApp/XenDesktop 7.7 Citrix have introduced Zones. Zones allow you to target Delivery Controllers, VDAs, Host Connections etc. against these zones which will basically be locations on your companies map i.e. Paris. Note that the SQL instance will still be shared from the primary site (the site you created initially). Other benefits are that you can create HDX policies, Machine Catalogs, Delivery Groups and tag them against a zone.
Citrix have stated that this is a phased-approach and Citrix will aim to improve and get around some challenges that still exist with this phase in future phases, such as the SQL constraint.
You can view a high level introduction to XenApp/XenDesktop 7.7 zones from Citrix here
Other enhancements shipped with XenApp/XenDesktop 7.7 include:
- Enhanced Citrix Director monitoring such as Desktop and Server OS usage reporting, SCOM integration, more secure authentication points.
- HDX Realtime Optimization Pack 2.0 with Skype for Business to bring uncompromised voice and video quality to the user when Skype for Business is hosted on XenApp/XenDesktop.
- PVS support for deploying Windows 10, provisioning to Azure with MCS.
- Improvements to functionality such as multiple reboot warnings (only one was given in previous XenApp/XenDesktop FMA versions), AppLimits (which allows an administrator to limit the number of simultaneous instances of resource-intensive applications thus maintaining server performance and prevent deterioration in service).
There only seems to be one different between installing v7.5/7.6 and v7.7. When creating a brand new Citrix Site, you have the option of specifying names and seperate locations for your Configuration Logging and Monitoring databases. Previously you would have needed to seperate and move the Monitoring and Logging databases as per Citrix best practice after site creation.
To view the installing XenApp 7.6 guide see here
Multiple reboot warnings
The new improved reboot notifications allow you to send notifications every 5 minutes if you send out an initial notification to users 15 minutes prior to a reboot. If you choose an initial notification 5 minutes or 1 minute before reboot you don’t get the option to send repeats. Users will only be notified of a reboot once in this case.
Application launch limits
AppLimits in XenApp/XenDesktop 7.7 allows you to limit the amount of time an application can run at any one time. This feature could come in handy if you have limited licenses to run an application or it is memory intensive and needs to be limited.
And as we have talked about, Zones is available in Citrix Studio to associate DDCs, VDAs etc. to specific regions according to your business map.
Here is just one example of a zone creation. You can see the resources I could assign to the zone I am creating.