On 22.05.2009 16:25, Ming Zhang wrote:> Hi All
>
> We want to use rsync to backup a live Berkley db to a remote site. BDB
> has a requirement that read has to be in the unit of db page size. So
> wonder how could we make sure that rsync can follow that? If we need
> to change the code, where we should begin to look at? Thanks!
The read block size is irrelevant, the problem you have is consistency.
If you want a working copy of a database (and this goes for any
database) you have to quiescent the database first. Otherwise the
file(s) in the filesystem may not be in a consistent state.
Also you must either quiescent the database the WHOLE TIME you back it
up, or you must use some form of snapshoting for the filesystem and then
backup the snapshot. (quiescent -> Snapshot -> unquiescent)
(Or use some other database depend backup procedure)
How you quiescent a database is about as database dependend as it can
get and personally i don't know how the procedure is for a BDB.
But i guess(!) you need cooperation from the program(s) working with the
db.
Googling: backup berkeley db
Appear to give answers, but i only took a quick glance.
Bis denn
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