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On Sat, 2009-05-02 at 17:33 -0400, Simon wrote: |
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> hi there! |
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> I've been using unison to synchronise and backup my computers. |
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> unison is based on rsync IIRC but with the difference that it |
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> 'remembers' the state of the folder that was synchronised. This way, |
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> if I delete a file on A, when sync'ing it will be deleted on B. While |
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> rsync would leave the file on B... |
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> |
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> I see rsync as a very good 'cp' program, but I need something that |
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> can deal with conflicts (file changed on both hosts/directories) and |
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> can propagate changes like deletes properly. Is there a way to get |
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> this behavior with rsync (maybe i missed something)? |
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|
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No. Unison implements the rsync protocol for transferring files, but it |
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does not actually use rsync itself. You can make rsync transfer files |
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that are not in either the destination or a "reference" location with |
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the --compare-dest option, for example if doing an incremental backup, |
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but this will not propagate the deletion of a file or directory. The |
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delete file will come back on the next synchronization. |
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|
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> The reason i'm asking is that unison has been having problems |
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> recently in sync'ing two pc... On my laptop, when i start the sync, |
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> it first checks it for changes against the 'unison snapshot'. Changes |
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> done since last sync are those that will be propagated. But it takes |
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> so long to check for changes (disk input rate is too slow i think) |
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> that once it finished, when it's time to send the changes to the |
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> remote server, the remote end has already disconnected! |
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> |
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> Thanks for the help/suggestions! |
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|
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If you are using ssh with unison, are you using the "KeepAlive yes" |
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option in your ssh configuration? If not, add it, and your connection |
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should not close from inactivity. If you are using direct sockets, |
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unison will use a keepalive so it can timeout if the communication link |
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is broken. |
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|
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How long is unison taking to check for changes? I can usually reconcile |
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changes in my home directory (approximately 45G, 125,000 files) in less |
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than 10-15 seconds between my slow laptop drive and a remote machine. |
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However, if you are syncing with a Windows machine, expect the sync to |
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be much slower. Fast checking is not safe on Windows, as unison can miss |
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changes, so it scans every file every time unless you tell it otherwise. |
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|
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Regards, |
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|
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Brandon Vargo |
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