Installation and Upgrade Guide

Overview of Installing G06.24
G06.24 Software Installation and Upgrade Guide—528593-005
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Falling Back to the Previous RVU
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You must install the IOAM enclosure as group 11, 12, 13, 14, or 15. The presence
of an IOAM enclosure in your system requires that certain other groups be left
empty. For more information, contact your service provider.
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You must isolate SWAN adapters on your system before you install an IOAM
enclosure. For more information, contact your service provider.
Migrating Existing Data to ESS
The migration of existing data from internal SCSI-attached, 514-byte sector disks to
industry standard, 512-byte sector disk subsystems includes an improved method for
checksum protection. The new checksum protection method employed for unstructured
files requires the data stored on disk be contiguous and aligned in units of 28KB.
When a non-partitioned unstructured file is created or migrated to ESS, the extent
sizes are rounded up to a mod-14 boundary, since an extent page is 2KB. This
ensures continuity of the data set protected by the checksum. This design ensures the
best possible performance for unstructured files, without adding significant overhead
for checksums. Each 28KB of data is protected with a 4KB check block, which contains
the checksum information.
Partitioned unstructured files cannot be migrated to an ESS without first performing a
migration of all partitions of the unstructured file set to a mod-14 extent boundary.
Partitioned unstructured files must use the same extent size and maximum extents for
all partitions because positioning is dependent upon a consistent size for each of the
partitions. Online migration attempts will abort when an unstructured partitioned file
without mod-14 extent sizes is present on the source disk.
Before attempting a migration to ESS, rebuild all partitions, using a mod-14 extent size.
Usually, this is accomplished by an offline copy to a new partition set.
The FCHECK utility (G06.24) includes a migration option that reports the files that
cannot be migrated to ESS because of this format limitation, in addition to reporting the
amount of disk space required for check block protection.
Falling Back to the Previous RVU
If you encounter a problem that cannot be resolved while running G06.24, you can fall
back to a previous G-series RVU, provided you have already installed the appropriate
fallback SPRs for your system.
Fallback SPRs are described in Section 3, Installing SPRs Before Upgrading to the
G06.24 RVU.