tar: /dev/rmt0: Cannot write: File too large tar: Error is not recoverable: exiting now This occurs write after reaching 2 GB limit.
I thought this was a problem with something else, not tar.. Try using bzip2 1.0 or higher, it allows greater than 2 GB backups.
The kernel shipped in 6.2 doesn't support files > 2 GB, that's why tar can't handle them. You need the Large Filesystem (LFS) kernel patch; either build your own kernel with it or get the Red Hat Linux Enterprise Edition which has LFS enabled by default.