zookeeper-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Flavio Junqueira <...@apache.org>
Subject Re: How to restore a snapshot after an accidental ZKclenup
Date Mon, 22 Feb 2016 15:03:43 GMT
Hi there,

I'm not sure what the API command you're referring to does. Does it delete the whole data
tree or a subtree or what? If you populate the data directory with a consistent snapshot/log
pair, then I don't see why you shouldn't be able to recover at least some of your data. The
sequence of steps should be:

- Copy appropriate files to the data/log directory of all replicas
- Start the replicas
- Check if it loaded the data tree successfully

In general, ZK doesn't need back up and what many applications end up doing is having a way
to reconstruct the data tree in the case of disaster, like deleting accidentally the whole
data tree.

-Flavio

  
> On 21 Feb 2016, at 08:29, AALISHE <aalishe@gmail.com> wrote:
> 
> Hi all,
> 
> I have a CDH cluster with  ZK 3.4.5   running on 3 nodes ....and one of the
> developers accidentlly ran an API command that does  zooKeeperCleanUp
> 
> I didnt know before this about ZK needing backups .... so there is no
> backup(s) on-hand.
> 
> But I see some kind logs and snapshot files under zookeeper lib/data
> (attached as well)
> 
> 65M Feb 19 05:48   log.900000001
> 18K Feb 19 07:19    snapshot.9000000a0
> 65M Feb 19 08:14    log.a00000001
> 18K Feb 19 08:21     snapshot.a00000759
> 65M Feb 19 08:22     log.b00000001
> 17K Feb 19 08:27     snapshot.c00000000
> 2 Feb 19 11:39        acceptedEpoch
> 21K Feb 19 11:39     snapshot.c000016c7
> 2 Feb 19 11:39         currentEpoch
> 129M Feb 20 04:21    log.c00000001
> 21K Feb 20 04:21     snapshot.d000184ec
> 65M Feb 20 17:50    log.d000184ed
> 23K Feb 20 17:50    snapshot.d0002bf88
> 4.0K Feb 20 17:50 .
> 65M Feb 21 03:24 log.d0002bf89
> 
> 
> 
> this incident happened  on  *Feb 20 17:50 *   .... as you can see the
> snapshot and log files stamped with earlier hour *Feb 20 04:21  *are larger
> insize....
> 
> 
> I think these last 2 files might the restore candidates?  if Yes  ... how
> do I properly restore to that point ??
> 
> 
> cheers!


Mime
View raw message