G06.24 Release Version Update Compendium

Hardware Products
G06.24 Release Version Update Compendium—528616-003
7-2
Fallback
Restrictions for the ESS include:
•
If you migrate data from a NonStop S-series system to an ESS and the data is
located on disks within I/O enclosures, these I/O enclosures must be populated
with I/O multifunction 2 (IOMF 2) CRUs.
•
Contractually, only ESS-trained technicians can handle or configure ESS
equipment. So, for any activities that involve installing, configuring, or operating the
ESS, the technician trained for working with the ESS must be on site and available.
To use ESS, you must:
•
Configure the storage array logical unit numbers (LUNs) and SCF configuration to
access them.
•
Use the new online data migration facility to move data to those LUNs.
•
Back up data from 514-byte sectored disks prior to data migration to ESS.
•
Retain a copy of the old CONFIG file, in case you need to perform a release level
fallback.
The migration of existing data from internal SCSI-attached, 514-byte sectored disks to
industry standard, 512-byte sectored disk subsystems includes an improved method
for checksum protection. The new checksum protection method employed for
unstructured files requires that the data stored on disk be contiguous and aligned in
units of 28 KB. For partitioned unstructured files requirements for ESS, see the G06.24
Software Installation and Upgrade Guide and the Interactive Upgrade Guide.
Fallback
No online fallback from 512-byte to 514-byte sectored disks is provided. Fallback
requires reverse migration of data in an offline manner.
IOAM
Introduced at G06.24, an I/O adapter module (IOAM) enclosure is a subsystem that
allows I/O operations to take place between the NonStop S-series and some fibre-
channel storage devices. The IOAM enclosure can be installed in a modular cabinet or
in a standard 19-inch rack. The IOAM enclosure fits into the NonStop S-series
tetrahedron as though the IOAM enclosure were an I/O enclosure.
IOAM is supported on the Tetra 8 and the Tetra 16 topologies. See the NonStop
S-Series Planning and Configuration Guide for details.
Migration
Certain limitations exist for configurations that include ESS or IOAM enclosures. For a
comprehensive list of these limitations, contact your HP representative.