IBM Enterprise Storage Server 2105 E10, Introduction And Planning Manual

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Table 2. IBM Enterprise Storage Server feature comparison (continued)
Feature Host Systems with SCSI or
Fibre-Channel Interfaces Host Systems with ESCON
Interfaces
Disk drive module (DDM) format Fixed block address (FBA) Count key data (CKD)
Peer-to-Peer remote copy (PPRC)
(See Notes 2 and 3.) Yes Yes
Concurrent Copy No Yes
Extended Remote Copy (XRC) No Yes
XRC planned outage No Yes (MVS operating systems)
FlashCopy (See Note 3.) Yes Yes
IBM Subsystem Device Driver (see
Note 1 below) Yes No
Multi-path locking facility (MPLF) No Yes
Multiple allegiance No Yes
Parallel-access volume No Yes
Notes:
1. See the ESS web site at
www.ibm.com/storage/hardsoft/products/ess/refinfo.htm
for details about host-system adapters supported with the ESS. See the following web site for details
2. This feature requires that you install an ESCON adapter on both the primary ESS and the secondary ESS.
3. The ESS does not support PPRC or FlashCopy on the AS/400.
Table 3 lists the physical features for the ESS.
Table 3. IBM Enterprise Storage Server physical features
Feature Description
Continuous availability, designed to virtually eliminate
single points of failure or repair (See Note 1.)
v
Cluster-processor complex failover
v
Device adapter failover
v
Concurrent maintenance
v
Failover/failback
Dual-cluster configuration
v
Eight cluster processors
v
Cache: 6 GB for Models E10 and E20, 8 GB standard
and optional 16 GB for Models F10 and F20
v
NVS: 384 MB
SSA device adapters Eight serial storage adapter loops (maximum)
Spare DDM (See Note 2.)
v
RAID 5 (6+P+S, 7+P)
v
RAID reconstruction with spare DDM
Read/write functions
v
Read/write cache
v
Fast-write NVS in storage server
v
Maximum sequential bandwidth
– 180 MB/second read
– 140 MB/second write
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ESS Introduction and Planning