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Robocopy /mon function without making a full pass

smccoskery asked
Medium Priority
Last Modified: 2012-08-13
Hi there,

I'm playing around with using robocopy /mon to keep my remote wan accelerator appliance's cache fresh.  Basically I'm mirroring data from my centralized file server to remove 'dummy' file servers.  By caching the traffic from the robocopy job on the remote wan accelerators, my remote users experience near lan-like access to the central file server, and the 'dummy' file servers are only accessed read-only, and only in the event of a wan failure.

Robocopy with the /MON /E switches works great for this, except I have one nagging complaint:  every time robocopy detects a change it kicks off a full copy job against the folder, which can take a long time for me due to number of objects in the folder, and the lack of speed on some of my wan links -- even though the only file that actually gets copied is the one that changed.

What I would like to do is schedule a full mirror job once a day (for cleanup), and have the monitor job (or something to replace it) running 24/7 that will copy a changed file immediately, and without checking the rest of the folders -- which takes too long and is creating unnecessary wan traffic.

Watch Question

Which verison of Robocopy?  The 2003 verison has a bandwidth limitor, as well as the ability to set how long to wait between copied.  /MOT:n   n=how long.  /IPG:n n=how many ms to wait between 64k packets.

This will not take care of the "monitor" job, for that type of functionality I would suggest something like WANSync.  

Sorry I could not help more.


I'm using version XP010.

Great,  You have the most current.

I for your full mirror I would do something like.  Robocopy source dest /COPYALL / MIR /IPG:5 /RH 2100-0300 /MON:100

The bandwidth for the /MIR is actully very small compaired to a full copy, and the 5ms time above will help, and I would increase this number by 5 until you find a good level.

This will Mirror all data, between the hours of 9pm and 3am, and rerun if there is more than 100 file changes during this time.

There are many Third Party products that will sync your data, using very little bandwidth, I use XOSoft WANSync.

Hope this helps


Thanks, I think I've got the syntax down I want for the full mirror job -- it's the job that will push changed files immediately I'm concerned with.

As an example, an idea I have is to use some kind of 'changed files' monitoring utility that I can have execute a script when a file changes, and be able to pass the changed file name to the script.  This is a utility I found that is close to what I need:  http://www.snapfiles.com/get/berkesnotify.html (but I don't know how to capture it's results).  The script would just copy the changed file to the remote server.  An added benefit of this is that I could write the script so the file got copied to multiple remote servers -- something I can't do with robocopy /mon without running multiple instances of it.

I realize replication software can do this job for me, but since my replication strategy is rather complex due to differing wan link speeds (I want to have granular control over which folders get replicated and to where), a scripted solution appeals to me... plus it's free.

PAQed with points refunded (500)

EE Admin

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