How to split / rar in parts large data archive files on Linux and Windows – Transfer big files across servers located in DMZ rescticted areas

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I was working on a Application Migration Project whose goal was to Install a business application called Asset Guardian and then move current company Data from the old server to the new AppServer.
F
or that purpose the company vendor Asset Guardian shipped to a Public access FTP, a huge (12GB) ZIP archive file which had to be transferred into a well secured DMZ-ed corporation network with various implemented Traffic Shaping Network policies, a resctrictive firewall allowing access to Internal Network only and to Few (Restrictive configured) Proxy Server IPs on port 80 and 8080.

One of the proxy servers allowed access to the Internet and I set this one and tried downloading the Huge Archive file  with the Windows 2012 server default browser Internet Explorer 10, though the download started it kept slow between ~ 300 – 500KB sec and when reached 3.4GB download failed. I tried resuming the download but as the remote Public FTP server where files resides doesn't support FTP RESUME function.
I thought it might be that Internet Explorer is badly managing the download so, I go forward and installed Portable Firefox (mirrored version 33.1.1 is here). Re-running download with firefox also failed, so the next logical step was for me to try downloading with Windows version of Wget (Wget) and with Portable Free Download Manager 3.9.14.1481 (mirrored here) using both of them was unable to complete download (probably due to firewall or Proxy screwing the proxy inspected traffic) thus I had to look for another way to copy the enormous archive into the company network.

To get around the issue I tried to download the file from FTP to another Server running Apache and tried re-downloading the big file archive (Asset-Guardian-data.zip) from Apache Webserver via HTTP protocol, this download method didn't work neither using plain HTTP protocol for download when downloaded file reached (3.4GB), thus I realized this is due to restrictive Proxy servers (dropping file downloads) bigger than  3.4GBs).

Then to be able to transfer the huge 12GB file, it seems the only left option was to to chop the big file on smaller file chunks and transfer them one by one.
In my case I had the Asset-Guardian-Files.zip transferred already to the Apache (Webserver) host which is running Linux so basicly the task was to Transfer Big archive file between the SuSE Linux Enterprise Server (SLES) 11 and Windows 2012 Server.

Quickesy way to do that is by using UNIX split command, i.e.:

split -b 1024m Asset-Guardian-Files.zip


The outputted files each 1GB are with naming (xaa, xab, xac, xad, xae, xaf, gaf etc.) in same folder where split command is run:

To later merge the files on the Windows 2012 server (copy) command is used:

copy /b file1 + file2 + file3 + file4 filetogether


In my case the command to issue on Win 2012 server was:

copy /b xaa + xab + xac + xae + xae + xaf + xaf + xag xah xai xaj xak Asset-Guardian-files.zip


This method to chop and transfer the file is most simple one and it doesn't require the two servers to have WinRAR or Console RAR / unrar installed.

If instead of Copy Huge File from Linux -> Windows host you need to copy too big file (lets say 100GB) between 2 Windows servers (Windows server host A and Windows server Host B – both situated in different firewall corporate networks) you will need to download to Win Host A and use Windows UNIX split equivalent tool called sfk (The Swiss File Knife) , sfk has port also for Mac OS so in case of need for need for migrating huge archive file from Mac OS X host it will serve as Linux's split – I've made SFK (current version) mirror here.

Another way to cut the 12GB file in parts and transfer to destination host via HTTP was to use rar (on the Linux host), then download the file on Win 2012 server and use Winrar Portable Free to extract the multiple files:

To make archive separate in parts set out to certain size out of a huge file with rar on Linux use:

cd /var/www
rar -a -v1000000k Asset_Guardian_Files.splitted.rar /var/www/Asset_Guardian_Files.zip

10000000Kbs = 10000000/1024 = 976MBs, hence rar produced parts will be sized to 976MB rar parts.

To find out archives check for *splitted*.rar in your /var/www

ls -al /var/www/*splitted*.rar
-rw-r–r– 1 root root 1048576 ное 28 18:34 Asset-Guardian-Files.splitted.part1.rar
-rw-r–r– 1 root root 1048576 ное 28 18:34 Asset-Guardian-Files.splitted.part2.rar
-rw-r–r– 1 root root 1048576 ное 28 18:34 Asset-Guardian-Files.splitted.part3.rar
-rw-r–r– 1 root root 1048576 ное 28 18:34 Asset-Guaridna-Filse.splitted.part4.rar

 

Then to download the files M$ Win 2012 server IE (http://my-linux-host.com/Asset-Guardian-Files.splitted.part1.rar, http://my-linux-host.com/Asset-Guardian-Files.splitted.part2.rar. etc.)

Thanks God, Problem Solved 🙂

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