Is this the original ICS FTP server component with your latest

Angus Robertson - Magenta Systems Ltd wrote:
> I have a problem with failed file uploads between the ICS FTP client
> and server when using passive mode, which may be related to the
> passive port pool.  For some reason, the passive port pool does not
> allocate sequential port numbers, but continually re-allocates the
> same numbers, if they have been freed.
> So one upload works fine, less than a second later an attempt to
> upload the next file fails with 'connection refused' in the client,
> perhaps because the same port can not be re-used so quickly?
> 21:59:53:779  ** > PASV
> 21:59:53:808  ** < 227 Entering Passive Mode (192,168,0,7,82,9).
> 21:59:54:544  ** < 226 File received ok
> 21:59:55:209  ** > PASV
> 21:59:55:239  ** < 227 Entering Passive Mode (192,168,0,7,82,9).
> 21:59:56:290  Upload Failed: Unable to establish data connection -
> Connection refused (#10061)
> Although the client fakes a 550 error for the connection refused
> error, it does not send any commands to the server, which keeps
> listening. After the failed upload, I retry the upload, but at this
> point the server is out of sequence and often responds with old
> responses, like: 
> 21:59:58:069  ** > PASV
> 21:59:58:101  ** < 226 File sent ok
> I've changed my application code to always send an AbortXfer command
> if the connection is refused, so the server gets back into sync with
> later commands.  Maybe AbortXfer should be in the FTP client code?
> But I'm wondering if passive mode should be using incrementing ports,
> and not the same ones all the time (my server only used four
> different ports for the four simultaneous clients).
> Note these FTP commands are passing through a VPN, three Sonicwalls, 
> two ADSL links and an ADSL bonding Firebrick, so the error could be
> elsewhere, although I still have to recover from it better.
> Angus
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