on one node that is up, and one node that is down. In this
case the read will fail because you haven't fulfilled the quorum (2 nodes
in agreement) requirement.
*- Original Message -*
*From:* Riyad Kalla rka...@gmail.com
*Sent:* Fri, July 27, 2012 8:08
*Subject:* Re: increased RF
On Mon, 2012-07-30 at 14:40 +0300, Tamar Fraenkel wrote:
Hi!
To clarify it a bit more,
Let's assume the setup is changed to
RF=3
W_CL=QUORUM (or two for that matter)
R_CL=ONE
The setup will now work for both read and write in case of one node
failure.
What are the disadvantages, other
How do you make this calculation?
Thanks,
*Tamar Fraenkel *
Senior Software Engineer, TOK Media
[image: Inline image 1]
ta...@tok-media.com
Tel: +972 2 6409736
Mob: +972 54 8356490
Fax: +972 2 5612956
On Mon, Jul 30, 2012 at 3:14 PM, Tim Wintle timwin...@gmail.com wrote:
On Mon,
On Mon, 2012-07-30 at 15:16 +0300, Tamar Fraenkel wrote:
How do you make this calculation?
It seems I did make a mistake somewhere before (or I mistyped it) - it
should have been 2.7%, not 2.8%.
You're sending read requests to RF servers, and hoping for a response
from CL of them within the
Thanks!
*Tamar Fraenkel *
Senior Software Engineer, TOK Media
[image: Inline image 1]
ta...@tok-media.com
Tel: +972 2 6409736
Mob: +972 54 8356490
Fax: +972 2 5612956
On Mon, Jul 30, 2012 at 5:30 PM, Tim Wintle timwin...@gmail.com wrote:
On Mon, 2012-07-30 at 15:16 +0300, Tamar
Quorum is defined as
(replication_factor / 2) + 1
therefore quorum when rf = 2 is 2! so in your case, both nodes must be up.
Really, using Quorum only starts making sense as a 'quorum' when RF=3
On 07/26/2012 10:38 PM, Yan Chunlu wrote:
I am using Cassandra 1.0.2, have a 3 nodes
Dave, per my understanding of Yan's description he has 3 nodes and took one
down manually to test; that should have worked, no?
On Thu, Jul 26, 2012 at 11:00 PM, Dave Brosius dbros...@mebigfatguy.comwrote:
Quorum is defined as
(replication_factor / 2) + 1
therefore quorum when rf = 2 is 2!
I think Dave is right, I have read this article again:
http://thelastpickle.com/2011/07/04/Cassandra-Query-Plans/
I have data on two nodes, and QUORUM read means it need read from both
two nodes.
I guess I need to increase the RF to 3, to make the system can tolerance
one node failure.
thanks
Ah!
Yan I think you want your writes to use QUORUM and your reads to just be a
single node right?
If you need/want the read-repair, then I suppose you would need more nodes
up (or deployed in your cluster) but if you are keeping 3 machines a RF of
2 with a write consistency of 2 and a read of 1
You have RF=2, CL= Quorum but 3 nodes. So each row is represented on 2 of the 3
nodes.If you take a node down, one of two things can happen when you attempt to
read a row.The row lives on the two nodes that are still up. In this case you
will successfully read the data.The row lives on one node
on one node that is up, and one node that is down. In this
case the read will fail because you haven't fulfilled the quorum (2 nodes
in agreement) requirement.
*- Original Message -*
*From:* Riyad Kalla rka...@gmail.com
*Sent:* Fri, July 27, 2012 8:08
*Subject:* Re: increased RF
I am using Cassandra 1.0.2, have a 3 nodes cluster. the consistency level
of read write are both QUORUM.
At first the RF=1, and I figured that one node down will cause the cluster
unusable. so I changed RF to 2, and run nodetool repair on every
node(actually I did it twice).
After the
12 matches
Mail list logo
