Unix True 64 - files ftp'd from VMS to Tru64 occasionally arrive as empty files ??

Author

files ftp'd from VMS to Tru64 occasionally arrive as empty files ??

James Blackmore

2004-03-01, 5:33 am

Just hope someone has any idea's on this. We have a script which
transfers files from a VMS system to Tru64 V5.1A every minute.

Files cannot be empty and smallest valid size is 73 bytes.

This mechanism generally works correctly, however about once or twice
a week we see an empty file on the Tru64 side, however checking the
file which was sent from VMS it was not empty.

I have searched for any known Tru64 ftp issues which might give this
behaviour, but can't find anything on this.

If there was a network or connectivity problem I would expect no file,
not an empty file.

I am trying to get a log file from the vms script when it ftp'd the
file which ended up empty so I can check if ftp logs n bytes sent (we
only keep logs for a few hours due to size, so this is hard to catch),
but if anyone has any other idea's on how this could be happening, I
would be grateful.

James.

Peter da Silva

2004-03-01, 12:34 pm

In article <e0ac4809.0403010213.1f7debc3@posting.google.com>,
James Blackmore <jblackmore@post.com> wrote:
> This mechanism generally works correctly, however about once or twice
> a week we see an empty file on the Tru64 side, however checking the
> file which was sent from VMS it was not empty.

Using FTP for file transfers by running an interactive client from a
script is fraught with problems, no matter what the OS. You need to at
least look at the output for messages indicating success and raise an
alarm if they're not there.

You could be running out of disk space on the sending side. Your script
may have a timing problem, so that the source file is being re-written
while it's trying to transfer it, the FTP client may be failing to read
from a locked file...

> I have searched for any known Tru64 ftp issues which might give this
> behaviour, but can't find anything on this.

Apart from disk space issues, I can't think of anything.

> I am trying to get a log file from the vms script when it ftp'd the
> file which ended up empty so I can check if ftp logs n bytes sent (we
> only keep logs for a few hours due to size, so this is hard to catch),

That's a start, but modifying the script so it flags and alerts you on
errors, or switching from interactive FTP to some more robust mechanism,
seems to be in order.

--
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Time for your nap. | Peter da Silva | Har du kramat din varg, idag? 'U`