[Info-vax] Potential loss of data problem in sftp client in TCP/IP Services ?

[glen herrmannsfeldt]

JF Mezei <jfmezei.spamnot at vaxination.ca> wrote:

(snip)
> When OS-X server (unix) would try to access VMS RFM=VAR files via NFS, I
> found that the auto conversion to standard unix termination only worked
> for the first portion of the file, after which, the data was sent raw
> without record delimiters (but the 2 byte length was part of the "blob"
> of data. I assumed it had to do with some buffering where the software
> was only able to convert from RFN=VAR to RFM=STMLF within a fixed size
> buffer and if the file was larger, then the rest didn't get converted.

When NFS requests data from the server, it gives the offset into
the file for the data it wants. Personally, I have never run an NFS
server that did any conversion. You can see, though, that if you didn't
read from the beginning sequentially through, that it wouldn't know
where in the file a specific offset was without reading from the
beginning. 

> But this predated 8.4 and the move of VMS to India. And does not seem to
> be what you are experiencing.

> And because this is sftp, you can't really use wireshark to see 
> what is being sent since it is encrypted. You'd need to somehow 
> enable debug logging on the unix host to see what is being sent.

Well, unix sftp pretty much writes the decrypted data stream to disk.
If anything is wrong, it is pretty likely that the VMS end sent
the wrong thing.

-- glen