[tahoe-dev] [tahoe-lafs] #1325: make `tahoe backup` useable as a replacement for rsync

[tahoe-lafs]

#1325: make `tahoe backup` useable as a replacement for rsync
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     Reporter:  chrysn       |       Owner:  nobody   
         Type:  enhancement  |      Status:  new      
     Priority:  major        |   Milestone:  undecided
    Component:  unknown      |     Version:  1.8.1    
   Resolution:               |    Keywords:           
Launchpad Bug:               |  
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Comment (by chrysn):

 two other issues came to my mind related to this, though both in the low-
 priority class:
 * sparse files (might actually be implemented, didn't test it)
 * hardlinks

 hardlinks are not too much of an issue server-wise due to the backuping
 node using the same convergence key, but when restoring, the file gets
 duplicated. (hardlinking all files from the same readcap is not a good
 idea either as they might originally have been distinct but had equal
 contents.)

 it might be reasonable to implement this by saving each file's device and
 inode number (i figure there has to be something compatible for each file
 system that provides hard links). that would solve it for the backup case
 (where all files are created more-or-less atomically), but is probably the
 wrong approach for a more general case where one wants to create arbitrary
 hard-links in tahoe-lafs. (one could argue that identical mutable file
 hashes are equivalent to hard-links, but then again that wouldn't work out
 too well for the backup scenario.)

-- 
Ticket URL: <http://tahoe-lafs.org/trac/tahoe-lafs/ticket/1325#comment:2>
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