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Zookeeper >> mail # user >> Backup/restore of an emsemble


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Re: Backup/restore of an emsemble
The nature of the system that I am working with is mostly read-heavy.
Writes happen rarely. In he event of disaster recovery to some point in
time in the past, the system should sustain minor inconsistencies.

I am also considering to have Zookeeper server create a copy of the
DataTree, and then serialize it into a file, which will later be picked up
by the import client. This could be the most efficient way of taking a
backup.

On Fri, Jul 5, 2013 at 11:33 AM, Flavio Junqueira <[EMAIL PROTECTED]>wrote:

> In your approach, would you "lock" the zookeeper state and read the data
> tree using getData/getChildren? If you have concurrent updates, then you
> may
> end up having an inconsistent snapshot.
>
> -Flavio
>
> -----Original Message-----
> From: Sergey Maslyakov [mailto:[EMAIL PROTECTED]]
> Sent: 05 July 2013 17:12
> To: [EMAIL PROTECTED]
> Subject: Re: Backup/restore of an emsemble
>
> Yes, Flavio, I looked at Exhibitor, but I need a pretty granular control
> over a cluster of ZK servers. This is why I'm inclined to build something
> by
> hand. So far, a pair of external export and import clients seems like a
> promising approach.
>
> Export would connect to the ensemble and dump out the data into a file on
> disk. Import would connect, wipe out the namespace, and then reload the
> data
> from the file that was earlier created by the export client.
>
>
>
> On Fri, Jul 5, 2013 at 8:31 AM, Flavio Junqueira
> <[EMAIL PROTECTED]>wrote:
>
> > Sergey,
> >
> > Have you had a look at Exhibitor?
> >
> > https://github.com/Netflix/exhibitor
> >
> > -Flavio
> >
> > -----Original Message-----
> > From: Sergey Maslyakov [mailto:[EMAIL PROTECTED]]
> > Sent: 05 July 2013 04:39
> > To: [EMAIL PROTECTED]
> > Subject: Backup/restore of an emsemble
> >
> > A while ago, Jack Ma asked this question:
> >
> > http://mail-archives.apache.org/mod_mbox/zookeeper-user/201306.mbox/%3
> > CCAB%2
> > BcfdyPDpbUh5FyDT%3D9mU%3DFCHEA1AZpkF6X0nN1t4mjwqu2tA%40mail.gmail.com%
> > 3E
> >
> > I wonder if there were any helpful suggestions that did not go into
> > the mailing list.
> >
> > I am mostly concerned about restoring data in a Zookeeper ensemble.
> >
> > There is no document at the project web-site that would explain the
> > restore procedure for a distributed deployment. The home-grown
> > solution that involves stopping the whole cluster, wiping out
> > databases on all but one server, restoring the database on one server,
> > and then bring up the cluster and pray that the populated server
> > becomes the leader and populates the cluster. Such solution seems to be
> too error-prone.
> >
> > Does anyone have recommendations on how to make it robust?
> >
> > Maybe there is a way to force-populate the ensemble remotely?
> >
> >
> > Thanks,
> > /Sergey
> >
> >
>
>