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I have a process that involves transferring files from the Windows LAN to an AIX UNIX server using FTP through a VPN connection.

The problem is that some of the files are very large -- up to 4gb. The VPN is fine with the smaller files, but chokes when the size is increased.

Is there a process I can follow to split a file on Windows XP, send to the server, and join back together on UNIX?

This is for a client, so I don't have the capacity to install anything very large on the Windows machine, and certainly not on the UNIX. Although a business case could be made for this issue, I'd say that would be a last resort.

Does anyone have any thoughts?

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can you be more specific about the type of UNIX ? (hp-ux solaris, AIX ?) – Sibster May 24 '12 at 10:07
cat should work fine to concatenate the files at the unix box. Also I found this:… – ReyCharles May 24 '12 at 10:15
@Sibster, it's AIX - see the first sentence ;-) – Nossidge May 24 '12 at 10:24
up vote 3 down vote accepted

7Zip allows you to create a zip archive and specify the maximum chunk size of a chunk. In windows right click the file 7zip -> add to archive... and chose the split size in the split to volume dropdown
And there is a client for windows, and most linux/unix flavors

As an alternative if you have cygwin on the windows side you could use split -b2 on the windows side and cat3 on the unix side. just make sure you cat the files in the correct order.

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Thank. This worked well with Dropbox's web brower upload which has a limit of 300MB per file. – Kevin P. May 9 '13 at 21:55

I would assume the answer is a combination of this: How to split large file on Windows?

and this: How can I combine several files into one?

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For file split, I use an open source tool sfk from sourceforge. It can be compiled on Windows and all Unix by one command (look for do-compile-unix batch in the zip). Then on first computer, use

sfk split 2g bigfile.dat outfile.dat

which makes 2 GB parts outfile.dat.part1, .part2 and like. On other computer, use

sfk join outfile.dat.part1 fullfile.dat

and it will join in correct sequence. Did not try AIX compile so far, but for example ARM embedded.

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Are you associated with this project at all or it's developer? If so please disclose this per the FAQ or this might be considered SPAM. – KronoS Jul 18 '12 at 23:02
@KronoS Well, it's open source, so … there's no one making money off it :) – slhck Jul 19 '12 at 2:47

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