The RDP data history is used to validate Predictive Failure Algorithms and identify Fibre Channel Links with degrading signal strength before errors start to occur. The new Fibre Channel Extended Link Service (ELS) retrieves signal strength. 

GLYPH<SM590000> FICON Dynamic Routing 

FICON Dynamic Routing (FIDR) enables the use of storage area network (SAN) dynamic routing policies in the fabric. With the z14 systems, FICON channels are no longer restricted to the use of static routing policies for inter-switch links (ISLs) for cascaded FICON directors. 

FICON Dynamic Routing dynamically changes the routing between the channel and control unit that is based on the Fibre Channel Exchange ID. Each I/O operation has a unique exchange ID. FIDR supports static SAN routing policies and dynamic routing policies. 

FICON Dynamic Routing can help clients reduce costs by providing the following features: 

– Share SANs between their FICON and FCP traffic. 

– Improve performance because of SAN dynamic routing policies that better use all the available ISL bandwidth through higher use of the ISLs. 

– Simplify management of their SAN fabrics by using static routing policies that assign different ISL routes with each power-on-reset (POR), which makes the SAN fabric performance difficult to predict. 

Clients must ensure that all devices in their FICON SAN support FICON Dynamic Routing before they implement this feature. 

## 9.7 z14 ZR1 RAS functions 

Hardware RAS function improvements focus on addressing all sources of outages. Sources of outages feature the following classifications: 

GLYPH<SM590000> Unscheduled 

This outage occurs because of an unrecoverable malfunction in a hardware component of the system. 

GLYPH<SM590000> Scheduled 

This outage is caused by changes or updates that must be done to the system in a timely fashion. A scheduled outage can be caused by a disruptive patch that must be installed, or other changes that must be made to the system. 

GLYPH<SM590000> Planned 

This outage is caused by changes or updates that must be done to the system. A planned outage can be caused by a capacity upgrade or a driver upgrade. A planned outage is usually requested by the client, and often requires pre-planning. The z14 ZR1design phase focuses on enhancing planning to simplify or eliminate planned outages. 

The difference between scheduled outages and planned outages might not be obvious. The general consensus is that scheduled outages occur sometime soon. The time frame is approximately two weeks. 

Planned outages are outages that are planned well in advance and go beyond this approximate two-week time frame. The distinction between scheduled and planned outages is beyond the scope of this chapter. 

