Help me with this Questiions

[Shachar Shemesh]

Harish wrote:

>I would like to understand the capabilities of GNU rsync software /
>utility. This is used for syncing file systems / file level data across
>two systems. I specifically would like to know its capabilities in
>syncing files – 
>
> 
>1)  How does it replicate data changes to  files – entire file or only
>the incremental blocks? 
>  
>
As far as I know, actual changes written to file are replacing the
entire file. Rsync's incremental nature only extends as far as the
network usage goes.

>2) Does it have any block level replication capabilities?
>  
>
Rsync is a file utility. It has no awareness of blocks. If you are using
Linux (you are not, I know), check out LVM for what you want. It has
generic "snapshots" support, which does what you want.

>3) Can it replicate files while the file is in open state (oracle redo
>log file)? This is particularly a problem in windows environment,
>typically. 
>  
>
Not unless the OS supports it. Rsync doesn't even have a "native"
Windows version at all. It only runs on Windows through an daptive layer
called "Cygwin", which brings the Unix semantics to rsync.

          Shachar