12.5 Migrating NSS32 to NSS64 volume using oes-nss32to64 service

Using DST, you can seamlessly move the NSS data from NSS32 to NSS64 volumes without noticeable change or disruption. The data migration is performed by migrating all the data and corresponding metadata from the source NSS32 volume to the target NSS64 volume in the same tree and server. The source and the target volumes must be local volumes.

NOTE:

Data migration process will not replicate the Primary Namespace of the NSS32 volume and Linux File Extended Attributes (setfattr) to the NSS64 volume.
If the target path already has a file with the same name as the source path, the system will not migrate that file.
For better performance, OpenText recommends one migration at a time.

12.5.1 Prerequisites

A new storage that is either equal or greater than the existing NSS32 volume.
A new NSS64 volume in a new or existing NSS64 pool.
The migration process requires minor downtime at the beginning for renaming the volumes and creating the shadow pair, followed by the removal of the DST pair at the end of the migration.
By default, the migration service (oes-nss32to64) is inactive and disabled. You must start oes-nss32to64 service (systemctl start oes-nss32to64.service) before you start the migration.

12.5.2 Data Migration

If the source NSS32VOL is already part of a DST pair, then you must break that DST pair.
Choose one of the following options to migrate the data from NSS32 volume (NSS32VOL) to NSS64 pool (NSS64POOL) using oes-nss32to64 service:
- Create a new NSS64 volume (NSS64VOL) in NSS64POOL and migrate NSS32VOL to NSS64VOL.
```
nss32to64 migrate NSS32VOL target-volume NSS64VOL
```
- Migrate NSS32VOL to NSS64POOL.
```
nss32to64 migrate NSS32VOL target-pool NSS64POOL
```
  Migration of NSS32VOL to NSS64POOL creates a new volume in NSS64POOL named NSS32VOL_64.
The oes-nss32to64 service performs the following migration steps:
1. Replicate the directory structure and the volume properties from NSS32VOL to NSS64VOL.
2. Swap DFS GUID from NSS32VOL to NSS64VOL.
3. Rename the NSS32 volume from NSS32VOL to NSS32VOL_32.
4. Rename the NSS64 volume from NSS64VOL to NSS32VOL.
5. Create a DST pair with NSS32VOL_32 as secondary volume and NSS32VOL as primary volume.
6. Move files from secondary volume NSS32VOL_32 to primary volume NSS32VOL.
7. After a successful migration, the oes-nss32to64 service removes the DST pair that was created in Step 2.e.
  
  Removing the DST pair mounts both volumes and makes them available for their independent use.
During the migration, you can check the following:
1. Verify the status of migration for a specific volume.
```
nss32to64 migration-status NSS32VOL
```
2. Check the status of all migrations.
```
nss32to64 list-migrations
```
  The list shows the percentage completion status, both completed and in progress.
If service issues or other problems cause the migration to fail, the migration is halted and you must resume the migration.
```
nss32to64 resume-migration NSS32VOL
```

For more information about nss32to64 command line utility, see Section B.6, nss32to64.