13 5:46 AM
To: "user@cassandra.apache.org"
Subject: Re: -pr vs. no -pr
>Sweeet, I %100 understand this now from these last few emails. It has
>always been a bit confusing.
>
>Thanks,
>Dean
>
>From: Sylvain Lebresne mailto:sylv...@datastax.com>>
>Reply-To:
t;>
Date: Friday, March 1, 2013 4:36 AM
To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>"
mailto:user@cassandra.apache.org>>
Subject: Re: -pr vs. no -pr
On Thu, Feb 28, 2013 at 11:39 PM, Hiller, Dean
mailto:dean.hil...@nrel.gov>> wrote:
Isn't i
On Thu, Feb 28, 2013 at 11:39 PM, Hiller, Dean wrote:
> Isn't it true if I have 6 nodes, I could run nodetool repair on just 2
> nodes(RF=3) instead of using nodetool repair –pr???
>
Yes, it is true.
And to precise further, in your case you have 2 options:
1) doing repair *without* -pr on 2 no
On Fri, Mar 1, 2013 at 12:39 AM, Hiller, Dean wrote:
> Isn't it true if I have 6 nodes, I could run nodetool repair on just 2
> nodes(RF=3) instead of using nodetool repair –pr???
>
> What is the advantage of –pr then?
I think the main advantage of nodetool is that you don't have to
calculate /
The way I've always thought about it is that -pr will make sure the information
that specific node originates is consistent with its replicas.
So, we know that a node is responsible for a specific token range, and the next
nodes in the ring will hold its replicas. The -pr will make sure that a
Isn't there more to it than that. You really have nodes responsible for
token ranges like so(using describe ring)
What we see is this from our describe ringŠ(1 to 6 are token ranges while
A to F are servers)Š.
A - 1, 2, 3
B - 2, 3, 4
C - 3, 4, 5
D - 4, 5, 6
E - 5, 6, 1
F - 6, 1, 2
With -pr, only
Hi,
Please note that I confirmed on v1.0.7.
> I mean a repair involves all three nodes and pushes and pulls data,
right?
Yes, but that's how -pr works. A repair without -pr does more.
For example, suppose you have a ring with RF=3 like this.
A - B - C - D - E - F
Then, a repair on A withou
Isn't it true if I have 6 nodes, I could run nodetool repair on just 2
nodes(RF=3) instead of using nodetool repair –pr???
What is the advantage of –pr then?
I mean a repair involves all three nodes and pushes and pulls data, right?
Thanks,
Dean
