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Accumulo >> mail # user >> METADATA recovery


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Re: METADATA recovery
I know in trunk, the ability to run `./bin/accumulo rfile-info -d
/accumulo/path/to/rfile`. If that's unavailable, you can run
`./bin/accumulo org.apache.accumulo.core.file.rfile.PrintInfo
-d /accumulo/path/to/rfile`. I'll defer to someone else for the walogs.

On Sun, Aug 19, 2012 at 12:50 AM, Denis <[EMAIL PROTECTED]> wrote:

> Hi.
>
> That is what am going to do.
> I still have terabytes of .rf files (!METADATA was the only table
> affected by the crash) and gigabytes of walog files and I am trying to
> extract info from them and insert into new database.
>
> Do you know any dumping tools for .rf and walog? (i started to create
> my own, but if there are existing ones, it could help to save the
> time).
> Am I right in understanding, that if all the content of .rf and walog
> will just be inserted into new db, VersioningIterator will remove all
> collision they may have ?
>
> On 8/19/12, John Vines <[EMAIL PROTECTED]> wrote:
> > When you have a namenode failure and you recover with teh Secondary
> > Namenode info, you're dealing with one level of potentially expired
> > pointers. On top of that, you have more layers of pointers WRT the root
> > tablet and !METADATA tablets. You can make attempts to recover, but what
> is
> > more apt to happen is you'll get a Root tablet up that has some, but not
> > all of the current !METADATA table files. And then the ones you get do
> get
> > up may or may not be pointing to the existing files for your tablets.
> >
> > What I'm ultimately trying to say is that you already lost some files,
> you
> > are more apt to lose more by trying to recover your old information
> instead
> > of taking what you have and starting over. I would suggest taking your
> > accumulo directory, moving it to accumulo_old or something along those
> > lines, reinstantiate an instance, and begin bulk importing the remaining
> > old information back into the new system.
> >
> > John
> >
> > On Sat, Aug 18, 2012 at 11:08 PM, Denis <[EMAIL PROTECTED]> wrote:
> >
> >> Hi.
> >>
> >> I have a trouble with my Accumulo installation.
> >> After hardware failure on NameNode, !METATABLE's root_tables is broken
> :(
> >>
> >> From "fsck /" output:
> >> ....
> >> /accumulo/tables/!0/root_tablet/A000ornd.rf: CORRUPT block
> >> blk_-8590712379082603283
> >> /accumulo/tables/!0/root_tablet/A000ornd.rf: MISSING 1 blocks of total
> >> size 896 B..
> >> ....
> >>
> >>
> >> What could you recommend to recover the data?
> >> Is it possible to reconstruct !METATABLE's root_tablet based on the
> >> rest of !METATABLE files ?
> >> Or is possible to reconstruct the whole !METATABLE based on th content
> >> of the all found tablets ?
> >> Are there any ready tools to do it ?
> >>
> >> Thanks.
> >>
> >
>