Application to Compare and Mirror a folder

Colbaker

Colbaker

Colbaker

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Hi all,

I have 2 folders that are identical (for backup purposes), is there a software that i can run that will look at both folders and if there are any differences then mirror those differences, for instance if 1 of the folders has some new files then this application copies them across to the other folder so both folders are then exactly the same?

Thanks
 
So for instance if i want to mirror C:\Folder with D:\Folder what would i put in using Robocopy? Also it does have lots of folders inside this folder?

Thanks
 
You can experiment with robocopy's options by using /L as well, which just has it tell you what it would do, given the folders and other parameters.

/MIR is one-way, so you do all your editing in one folder, and after robocopy'ing the files with that option, the other folder is identical (including deleting any files that you had deleted in the original).

If you needed 2-way sync, in case it's not clear when files will be added or updated, you'd instead need something like:

robocopy locationA locationB /e /m /xo
robocopy locationB locationA /e /m /xo

When using something like that, you'd need to be sure the clocks for both locations (if residing on different computers / servers) are sync'd up, and when you want to delete a file, delete it in both before doing the next sync else it'll keep reappearing again. May not need both /m and /xo, and /m usage depends on whether you also run some backup software that tends to reset the archive attribute or not already.

Definitely do some test runs either way with dummy folder structures first. You can then check with a /L run until you get the options right, then when happy do a non /L run and let it do its thing. Then simulate some typical file changes you'd do, and try again first with /L then if happy, without.

Once you've got it, it should work well for you, just one of those many ways to skin a cat scenarios to get it just how you need - or maybe the /MIR option is already that :D

P.s. Yay, 250 posts!
 
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Ok, The one issue i seem to have with Robocopy is it is taking ages, I started it last night at about 2030 and it is still going this morning, The source folder is 165gb and the destination folder already has most of the same files in, Is there anything that will only search for new files and transfer them?
 
Robocopy /e "C:\source" "D:\destination"

I'm not keen on the MIR switch

Once it's been run once, it takes my 65gb folder a matter of seconds to scan through for changes (over the network too)
 
Robocopy is your best solution, but if you aren't inclined to learn the switches then use synctoy with care. It's easy to use, but does have issues with long filepath names - it ignores them and doesn't log it either. I found this out the hard way, but it's well documented if you search.
Your first sync will always take a while btw, subsequent syncs will be considerably faster.
 
Another vote for SyncToy. I've been using it for years without issues. The preview feature is very useful.

Maybe all my filenames are very short. :p
 
That's insane

I've told robocopy to run before (where it had to copy about 1500gb over the network) it did it at the same rate that manually copying it would.. ie, within a working day

Robocopy runs at the full speed of your network/hard drive limitation I find, with a few milliseconds pause to scan each file
 
Colbaker said:
I think i am gonna give Synctoy a try as Robocopy is STILL doing it's thing.
Click to expand...
I'm not a fan of SyncToy, it's slow, feature-limited, unreliable (in my experience) and has a nasty habit of failing silently as someone else mentioned above. If you want a GUI-based syncing utility, try FreeFileSync, it's better in every respect.

Having said that, I've never had any major speed issues with Robocopy... have you ruled out any problems with one or both of your HDDs?
 
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