IBM Elastic Storage System 3200, Service Manual

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PortFast
A Cisco network function that can be configured to resolve any problems that could be caused by the
amount of time STP takes to transition ports to the Forwarding state.
R
RAID
See redundant array of independent disks (RAID).
RDMA
See remote direct memory access (RDMA).
redundant array of independent disks (RAID)
A collection of two or more disk physical drives that present to the host an image of one or more
logical disk drives. In the event of a single physical device failure, the data can be read or regenerated
from the other disk drives in the array due to data redundancy.
recovery
The process of restoring access to file system data when a failure has occurred. Recovery can involve
reconstructing data or providing alternative routing through a different server.
recovery group (RG)
A collection of disks that is set up by ESS, in which each disk is connected physically to two servers: a
primary server and a backup server.
remote direct memory access (RDMA)
A direct memory access from the memory of one computer into that of another without involving
either one's operating system. This permits high-throughput, low-latency networking, which is
especially useful in massively-parallel computer clusters.
RGD
See recovery group data (RGD).
remote key management server (RKM server)
A server that is used to store master encryption keys.
RG
See recovery group (RG).
recovery group data (RGD)
Data that is associated with a recovery group.
RKM server
See remote key management server (RKM server).
S
SAS
See Serial Attached SCSI (SAS).
secure shell (SSH)
A cryptographic (encrypted) network protocol for initiating text-based shell sessions securely on
remote computers.
Serial Attached SCSI (SAS)
A point-to-point serial protocol that moves data to and from such computer storage devices as hard
drives and tape drives.
service network
A private network that is dedicated to managing POWER8 servers. Provides Ethernet-based
connectivity among the FSP, CPC, HMC, and management server.
SMP
See symmetric multiprocessing (SMP).
Spanning Tree Protocol (STP)
A network protocol that ensures a loop-free topology for any bridged Ethernet local-area network. The
basic function of STP is to prevent bridge loops and the broadcast radiation that results from them.
44 IBM Elastic Storage System 3200: Service Guide