# Tahir Hassan's Blog

My Technical Notes

## Thursday, 8 June 2017

### One-way Sync (Mirror) using Robocopy

Before mirroring one directory with another, you want to first check how long the mirroring will take, if you think it will be a big job. To only check what will be copied across and not actually do it, add a flag /L to the options.

Example  The following statement does a sync from the source location C:\_todo to the destination Z:\_todo:


robocopy C:\_todo\ Z:\_todo /MIR /NJH /XF *.org~ *.org# /XD .git


The first argument is the source location, second the destination. Here are the remaining arguments:

• /MIR tells it to mirror a location.
• /NJH tells it to not produce a job header, which contains information like the source and destination directories. This is only needed if you log this information to a file that will be later viewed.
• /XF is a list of file name patterns to exclude. Separate them by space.
• /XD is a list of directory name patterns to exclude. As with \XF, separate them by space.

Information Produced  In the information produced, you have a list of items that will be copied across, and the most important bit, especially if you run it with the /L for logging, is the Bytes Copied in the footer, which is 22.6 K (kilobytes) in the output below:


\$>
17    C:\_todo\
New File                  30        .#30-May-2017-Onwards.org
New File               13014        30-May-2017-Onwards.org
New File                  94        compare.bat
New File                1660        gregg.org
New File                 317        May2017.org
New File                  36        myday-1235.org
New File                 229        myuol.org
New File                   0        printertile.org
New Dir          0    C:\_todo\Archive\
New Dir          1    C:\_todo\NdorChangesv2\
New File                7782        NdorChangesv2.org

------------------------------------------------------------------------------

Total    Copied   Skipped  Mismatch    FAILED    Extras
Dirs :         4         2         2         0         0         0
Files :        18        10         8         0         0         0
Bytes :    51.6 k    22.6 k    28.9 k         0         0         0
Times :   0:00:00   0:00:00                       0:00:00   0:00:00

Ended : Thu Jun 08 15:00:29 2017