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The Question is: I recently moved some Isamed data files from our Vax 4000 over to a NT server to back the files up to tape. I retrieved some files from the NT backup tape and found the file type changed from "indexed" to "sequential". I am unable to convert the file back to isamed because the record format was changed to "stream" instead of "fixed length". Is there a solution? Is there always a problem moving files from a VMS system to NTs NTFS? The Answer is : You have now learned why any BACKUP strategy should be completely tested -- and tested before it is needed. The OpenVMS file system differs from those of the various Microsoft platforms, from those of UNIX, Apple MacOS, and of other operating systems. When transferring files across heterogenoous platforms via FTP, NTDS, NFS, DECnet or other mechanism, some information may be lost in the conversion. To save OpenVMS structured files to another system, you must ensure that the file attribute metadata associated with the file is also saved. One method would be to use ANALYZE/RMS/FDL to generate the FDL for the source file. CONVERT the file to a known format that is compatible with the target platform, then store BOTH files. Restoring involves CONVERTing the file back to its original format using the FDL. Another (and more common) approach involves packing the files into a BACKUP saveset or into a zipfile using the zip tool, and storing the saveset or zipfile. (You can also zip a BACKUP saveset, and this can potentially compress the saveset.) OpenVMS versions of zip tend to support the "-V" option, which will preserve the OpenVMS file attributes metadata. If you can determine the FDL for the original indexed RMS file, you may be able to recover the file from your existing sequential stream version using the CONVERT/FDL utility. For a DCL command procedure that will restore the attributes of a corrupted BACKUP saveset, please see the OpenVMS FAQ.
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