doc/forum/cannot_sync___39__unused__39___files.mdwn

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+Hi,
+
+I have setup a remote git-annex repository (ssh into some machine in our local network) which I will call "common_repo".  Multiple contributors will then be cloning this repo into their laptops (I will call "client_repos").
+
+When these client_repos change and do a "git annex sync <common_repo> --content", all the files from their laptops are successfully synchronised.  The problem arises when:
+
+(1) CLIENT_A creates somefile.csv
+(2) CLIENT_A commits somefile.csv
+    i.e. git annex add somefile.csv
+          git commit -a -m "uploaded somefile.csv"
+(3) CLIENT_A modifies somefile.csv
+(4) CLIENT_A commits modified somefile.csv
+    i.e. git add somefile.csv
+         git commit -a -m "updated somefile.csv"
+(5) CLIENT_A synchronises with common_repo
+    i.e. git annex sync <common_repo> --content
+
+If I check the .git/annex/objects of common_repo, I can't seem to find a copy of the unmodified somefile.csv.  It only has a copy of the latest somefile.csv.
+
+This is problematic if one client tries to checkout a revision of the project that uses the original somefile.csv.
+
+I learned that I can change the preferred content of git-annex.  So, the appropriate preset for common_repo seemed to be "backup".  After running the commands in common_repo:
+    git annex wanted . standard
+    git annex group . backup
+
+I've done another test of the scenario above, and common_repo is still missing the previous revision of the file!!  The preferred file content of common_repo should be "include=* or unused".  In my case, the previous version of somefile.csv will probably fall in the "unused" category.  But I still cannot find it.
+
+A workaround is using two commands from the client(s):
+    git annex copy --to <common_repo> --all
+    git annex sync <common_repo> --content
+
+But I can imagine my users forgetting to run 'copy' and my repo will go to shit over time.
+
+Any ideas why I can't synchronise 'unused' files?
+