High Availability for RDS
Table of Contents for all RDS related
High Availability for RDS using Windows Server 2008 and 2008 R2 is discussed at this link. For Windows Server 2012 and 2012 R2, the recommendations have not changed dramatically.
A graphical overview of an RDS deployment:
Here are the RDS roles:
- Remote Desktop Session Host (RD Session Host) in redirection mode
- Remote Desktop Connection Broker (RD Connection Broker)
- Remote Desktop Virtualization Host (RD Virtualization Host)
- Remote Desktop Web Access (RD Web Access)
- Remote Desktop Gateway (RD Gateway)
- Remote Desktop Licensing (RD Licensing)
1. RD Session Host in redirection mode
A high availability solution for the RD Session Host server consists of high availability of the hardware, as well as high availability of the Remote Desktop Session Host role service. You can use multiple RD Session Host servers and round robin DNS to provide high availability at both levels. High availability is obtained by virtue of the Remote Desktop Protocol (RDP) client trying all the IP addresses returned by the DNS server. All the RD Session Host servers should be running in active-active mode.
2. RD Connection Broker
Similar to RD Session Host, the RD Connection Broker role service can be made highly available at both the hardware and the service level by clustering multiple servers running the RD Connection Broker role service. Failover clustering guarantees that in the event of hardware or software (service) failure on the active node, a failover is triggered. In other words, a new active node would be selected at that time. A step-by-step guide about how to configure an RD Connection Broker server in an active-passive mode for high availability will be available soon on TechNet.
3. RD Virtualization Host
The Microsoft VDI solution supports highly available Hyper-V virtual machines. Setting up a failover cluster environment with multiple Hyper-V hosts will ensure that in the event of a hardware failure on a Hyper-V host, the virtual machines will fail over to another Hyper-V host and automatically start. If the Remote Desktop Virtualization Host Agent service fails, this service is configured to restart automatically. Thus all the Hyper-V virtual machines would be available all the time.
4. RD Web Access
High availability of the RD Web Access role service is achieved by deploying it in an active-active mode. Multiple RD Web Access servers can be configured as part of a Network Load Balancing (NLB) cluster to achieve this. You could also use round robin DNS in place of an NLB cluster to make the RD Web Access role service highly available.
5. RD Gateway
For high availability of RD Licensing and RD Gateway, see the following:
6. RD Licensing
RD Licensing is best made highly available by setting up 2 or more RD licensing servers, configuring each RDSH server to use all of these RD licensing servers. The CAL's purchased should be 'split' across these RD Licensing servers. With that configuration, even if a single RD License Server is down, the RDSH server will continue to query other RD License servers to obtain a valid CAL for an end user or device.
Unsupported high availability deployment configurations
There are two deployment configurations that are not supported:
- Clustering RD Connection Broker servers on RD Virtualization Host servers.
- An active-active RD Connection Broker installation.