Server groups overview
Server groups are designed to work with BMC Remedy AR System in any type of supported environment that has more than one server. This includes large distributed setups that make use of hardware load balancers and the Distributed Server Option (DSO). The AR System server groups feature provides failover management for crucial operations, server scalability, application-level load balancing, and the sharing of floating licenses among the servers. A server group consists of two or more AR System servers that are managed as a single unit. The servers share the same AR System database, but perform workflow and database updates independently from each other.
The servers within a server group need not have the same operating system, but you should ensure that any workflow that interacts with the operating system will run on all operating systems within the server group.
AR System servers in a server group
A server group acts as a single AR System server to support applications running on multiple AR System servers. The individual servers in the server group are configured to spread the load of shared services, and to provide backup for each other to ensure that those services are always available. BMC applications that are based on AR System, such as the BMC Atrium CMDB and its related applications, as well as the BMC Remedy ITSM suite of applications can be installed and configured to operate within a server group.
To ensure high availability of AR System operations, a server group can be configured to provide failover protection by assigning rankings for specific AR System operations to the servers in the group.
Benefits of using a server group
The following are the benefits of configuring your AR System implementation using a server group:
- Heavy user traffic can be distributed across multiple AR System servers using a third-party load balancer.
- Automatic server failover (if a server goes down the system seamlessly keeps running).
- Ease of administration; it has only one database to manage and back up.
- AR System servers share all BMC software licenses except AR Server licenses.
- There is one server designated as an administrative server. (When the workflow and applications are handled on the administrative server, the changes are automatically propagated to other servers in the group.)
- Specific servers in the group can also be configured to handle reporting, reconciliation, and other tasks that can impact performance, freeing up the remaining servers in the group to handle user traffic.
- Inexpensive servers can be added to a server group to increase the growth in users and workload without having to replace or upgrade a single server. The environment is easier and less expensive to scale.
Server groups also work in conjunction with hardware load balancers that direct user traffic to some or all servers in the group. For best performance and reliability, BMC recommends that you use a load balancer when implementing server groups. For specific details on using a load balancer, see Configuring a hardware load balancer with BMC Remedy AR System and Using a load balancer with server groups.
Recommendations on when to use a server group
Implement a server group if you require failover protection, or if you have a large environment that requires multiple servers. AR System can be setup to run on multiple servers without using a server group, and there may be some cases where that is the best solution, however the recommendation for running multiple servers is to install them as a server group.
It is required to always use the exact same version and patch level for all BMC software applications on each server included within a server group. And, to always upgrade each application on each server within the server group at the same time.