Preserving IBM Spectrum Scale ACLs of transferred files

Ascp and Aspera Sync can preserve NFSv4 and POSIX ACLs and immutability attributes when transferring files from an IBM Spectrum Scale (formerly GPFS) cluster to another cluster.

Preserving Spectrum Scale ACLs

To preserve file attributes and permissions when transferring from one Spectrum Scale cluster to another, run ascp or async with the --preserve-xattrs=native option.

Preserving expiration attributes of immutable file sets

To preserve expiration attributes, use timestamp preservation options:

  • Ascp: Use --preserve-access-time to preserve only the expiration attributes or -p to preserve all timestamps.
  • Aspera Sync: Use --preserve-access-time.

Important behavior notes

Attribute preservation:

  • Pools, replication, and cloning attributes are not preserved from source to destination.
  • In Aspera Sync transfers, security attributes are preserved only when the user on both endpoints is root.

Immutable files and directories:

  • Immutable directories on the source are not set as immutable on the destination. This ensures that the contents of the directory can be transferred.
  • When the destination file exists and the source file is changed to immutable (immutable: yes), ascp and Aspera Sync update the destination file from mutable to immutable. However, if the source file is changed back to mutable (immutable: no), the change cannot be applied to the destination file because it is still immutable. Manually change the destination file after which ascp and Aspera Sync can write content and permissions changes.
  • When the destination file exists and is immutable, ascp and Aspera Sync return an error for the immutable file (Destination: Read-only file system) and then transfers any other files in the transfer.

Append-only files:

  • When the source file is an append-only file (appendOnly: yes), it can be transferred once to the destination. After the initial transfer, it cannot be updated by ascp or Aspera Sync because FASP must overwrite the file.
  • When the destination file exists and is an append-only file, ascp and Aspera Sync either stop the rest of the transfer (for Spectrum Scale 5.0.1), or return an error for the file (Destination: Read-only file system) and then transfers any other files (for Spectrum Scale 5.0.0). To avoid transfer failures, exclude append-only files that exist on the destination from consideration on the source.