IBM z13s, Technical Manual

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IBM z13s Technical Guide
IBM zAware improves the overall RAS capability of z13s servers by providing these
advantages:
򐂰 Identify when and where to look for a problem
򐂰 Drill down to identify the cause of the problem
򐂰 Improve problem determination in near real time
򐂰 Reduce problem determination efforts significantly
For more information about IBM zAware, see Appendix B, “IBM z Systems Advanced
Workload Analysis Reporter (IBM zAware)” on page 453.
9.9 RAS capability for Flash Express
Flash Express cards come in pairs for availability, and are exclusively in PCIe I/O drawers.
Similar to other PCIe I/O cards, redundant PCIe paths to Flash Express cards are provided by
redundant IO interconnect. Unlike other PCIe I/O cards, they can be accessed only by the
host by using a unique protocol.
In each Flash Express card, data is stored in four solid-state drives (SSDs) in a RAID
configuration. If an SSD fails, the data is reconstructed dynamically. The cards in a pair mirror
each other over a pair of SAS cables, in a RAID 10 configuration. If either card fails, the data
is available on the other card. Card replacement is concurrent, and does not cause disruption
to your operations.
The data is always stored encrypted with a volatile key, and the card is usable only on the
system with the key that encrypted it. For key management, both the Primary and Alternate
SEs have a smart card reader installed.
Flash Express cards support concurrent firmware upgrades.
Figure 9-2 shows the various components that support Flash Express RAS functions.
Figure 9-2 Flash Express RAS components
For more information about Flash Express, see Appendix H, “Flash Express” on page 529