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Dell HPC NFS Storage Solution - High Availability (NSS-HA) Configuration with Dell PowerVault
MD3260/MD3060e Storage Arrays
10
o With the RAID-6 8+2 choice for the virtual disk configuration, six virtual disks can now
be constructed for each PowerVault MD3260 or MD3060e storage array (60 / (8+2) = 6).
An 180TB configuration consists of a single PowerVault MD3260 and the logical volume
will contain six virtual disks. A 360TB configuration which consists of a PowerVault
MD3260 and a PowerVault MD3060e will have a total of twelve virtual disks. The logical
volume uses six virtual disks from the MD3260 and it is extended with the other six
virtual disks from the MD3060e. As demonstrated by the results of the I/O performance
tests, a stripe element size of 512 KiB can significantly enhance the sequential I/O
performance in this configuration over the stripe element size of 1024 KiB used in the
previous versions of NSS-HA solutions.
Section 4 and 5 provide detailed information about the high availability functionality and I/O
performance tests.
Table 2 summarizes the differences in storage systems for the previous and current version of NSS-HA
solutions.
Storage components in NSS-HA Table 2.
NSS4-HA release
(July 2012)
“PowerEdge 12
th
Generation based
solution”
NSS4.5-HA
(September 2012)
“PowerVault MD3260/MD3060e based
solution”
Storage
configurations
144TB: 1 PowerVault MD3200 + 3
PowerVault MD1200s.
288TB: 1 PowerVault MD3200 + 7
PowerVault MD1200s.
180TB: 1 PowerVault MD3260.
360TB: 1 PowerVault MD3260 + 1
PowerVault MD3060e.
Disks in
storage array
3TB NL SAS.
Virtual disk
configuration
RAID-6 10+2, a virtual disk is created
using all 12 disks in a storage array.
Segment size 512KiB.
Write cache mirroring enabled.
Read cache enabled.
Dynamic cache read prefetch enabled.
RAID-6 8+2, a virtual disk is created
across all five drawers in a storage array,
two disks per drawer.
Segment size 512KiB.
Write cache mirroring enabled.
Read cache enabled.
Dynamic cache read prefetch enabled.
Storage
enclosure
cabling
Asymmetric ring cabling scheme.
Chain cabling scheme.
Logical
volume
configuration
Stripe element size: 1024KiB.
Number of stripes: 4.
Number of virtual disks per logical
volume:
4 for 144TB configuration
8 for 288TB configuration.
Stripe element size: 512KiB.
Number of stripes: 6.
Number of virtual disks per logical
volume:
6 for 180TB configuration
12 for 360TB configuration.