When planning the configuration of your High Availability (HA) network, you have to decide whether you want to install the UMS Server and UMS Load Balancer on the same host or on separate hosts. At the same time, there is a question how many UMS Servers and UMS Load Balancers are required. The following article describes the most common use cases and provides only general sizing recommendations. Your individual configuration may differ.

When deciding how many UMS Servers and UMS Load Balancers you need, simply counting your endpoint devices is not enough. Most importantly, you have to analyze the entire network environment as well as the other circumstances within your workplace. See Installation and Sizing Guidelines as well as Installation Types & Diagrams and contact your IGEL reseller to get counsel.

UMS Server & UMS Load Balancer Are Installed on the Same Host Machine

The most common scenario when deploying UMS High Availability is to install the UMS Server and UMS Load Balancer on the same host machine. Both the UMS Server and the UMS Load Balancer offer redundancy and are installed on two servers. The database is ideally designed as a cluster.

Typical Use Cases

#UMS Server + UMS Load Balancer

The installation on the same host machine is suitable if

2 UMS Servers 
2 UMS Load Balancers

In this configuration, each of the two servers can also perform the tasks as a UMS Server alone. If both servers are active at the same time, this has a load-distributing effect. Note, however, that the load balancer generates extra load along with the actual UMS Server.

UMS Server & UMS Load Balancer are Installed on Separate Host Machines

If you need to manage a very large number of devices and/or do not want the server resources to be shared between the load balancer and the UMS Server, the installation on separate hosts should be considered.

Typical Use Cases

#UMS Server Standalone
& Load Balancer Standalone

The installation of the load balancer on a separate host machine is

  • required if the number of devices > 50,000
  • recommended if you do not want the load balancer to consume resources on the UMS Server host

Smallest typical configuration:

2-3 UMS Servers
2 UMS Load Balancers

General sizing recommendations:

  • up to 6 UMS Servers
  • up to 3 UMS Load Balancers
  • 1 UMS Server per max. 50,000 devices
  • 1 LB per max. 3 UMS Servers

In the smallest typical configuration, queries from the devices are passed on to the UMS Servers by both load balancers. If one of the load balancers should fail, the other remains available and assumes responsibility for communications alone. A great number of UMS Servers could overload a single load balancer, which would then become itself a bottleneck. Therefore, there are provisions for no more than three UMS Servers in this configuration. For very large installations with more than three UMS Servers, the number of load balancers should be increased accordingly.

The UMS Server and UMS Load Balancer must be in the same IP network. There must be NO NAT or proxies between the UMS Server and UMS Load Balancer because they can influence communication between the components. 
If there is a firewall between the UMS Server and UMS Load Balancer, it must be configured according to UMS Communication Ports.