That makes sense. Thank you.

On Wed, Oct 18, 2017 at 6:58 PM, Sean Busbey <[email protected]> wrote:

> When a HBase Master believes a RegionServer is dead, the first step in
> recovering impacted regions[1] is to take over the HDFS leases of its
> WAL files. This prevents the RegionServer from continuing to accept
> edits and will cause it to abort once it sees the lease is gone.
>
>
>
> [1]: http://hbase.apache.org/book.html#_wal_splitting
>
> On Wed, Oct 18, 2017 at 9:56 AM, Nikita Marshalkin <[email protected]>
> wrote:
> > Hi,
> >
> > I've got a question about HBase consistency guarantees,
> > especially linearizability,
> > and can't find the answer in the documentation.
> >
> > Consider the following scenario:
> >
> > 1. There is a network split between RegionServer and (Zookeeper and
> Master)
> > 2. Master reassigns region to another RegionServer
> > 3. Region hasn't reacted yet to ZK session expiration and still believes
> > that he is in game
> >
> > Now there are two RegionServers that think they are "the right one"
> >
> > Clients with outdated cache are communicating with the failed one, while
> > others are writing to the new one.
> > It violates assumption "single RegionServer for a region"
> >
> > What am I missing?
> > --
> > Yours sincerely,
> > Nikita Marshalkin.
>



-- 
Yours sincerely,
Nikita Marshalkin.

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