How IBM Multi-site Workload Lifeline (Lifeline) works

Load balancing workloads

Lifeline uses two tiers of load balancing for workloads targeting TCP/IP applications. Lifeline directs first-tier load balancers to route workload connections to second-tier load balancers in the selected site, which then route the connections to applications in the site. Lifeline relies on IBM MQ® clusters for workloads using messaging. Lifeline directs the cluster to route workload messages to IBM MQ queue managers in the selected site, which then make the messages available to applications.

Site routing recommendations

For workloads using two tiers of load balancers, Lifeline provides first-tier load balancers with site connection routing recommendations based on the availability and health of the workload applications, the z/OS systems and (if applicable) Linux® on IBM Z systems across both sites. For workloads using IBM MQ clusters, Lifeline provides the cluster with site message routing recommendations based on the availability and health of the IBM MQ queue managers and the z/OS systems across both sites.

Lifeline Advisors and Lifeline Agents

Lifeline consists of Lifeline Advisors and Lifeline Agents. If Lifeline Agents detect that all workload applications or IBM MQ queue managers in a site are down or unhealthy, the Lifeline Advisor will declare a workload failure. If Lifeline Agents detect that all z/OS systems and (if applicable) Linux on IBM Z systems within a site are no longer available, the Lifeline Advisor will declare a site failure. In either case, new requests for the workload can be routed to the other site.

Workload configurations

An Active/Standby workload consists of workload connections that contain transactions which update databases on z/OS® systems. Lifeline ensures that connections for these update workloads get routed to only one site at any time. An Active/Query workload consists of workload connections that contain transactions that only query databases on z/OS systems. Lifeline allows connections for these query workloads to get routed to either or both sites at any time.

Planned outages

If you to need to bring a workload down for a scheduled maintenance window, Lifeline allows you to now keep the workload available by moving it seamlessly from one site to another. This is accomplished by using Lifeline commands that influence where workload requests get routed.

Technical details

Software requirements

Virtualization on z/VM requires Version V5R3 or newer.

Virtualization on z/OS requires z/OS Version V2R1 or newer running Communications Server for z/OS.

    Hardware requirements

    Any System z that can run z/OS V2R1 or higher and uses the TCP/IP stack from the Communications Server for z/OS.