Read Repairs and CL

Looking at the wiki for the read path ( http://wiki.apache.org/cassandra/ReadPathForUsers), in the bottom diagram for reading with a read repair, it states the following when "reading from all replica nodes" after there is a hash mismatch: If hashes do not match, do conflict resolution. First

Re: New data center to an existing cassandra cluster

Yes , RF=3 in existing datacenters DC1 & DC2 and going to be same RF in new datacenter DC3 which I'm going to add. On Sat, Aug 27, 2016 at 11:15 PM, Alexander DEJANOVSKI < adejanov...@gmail.com> wrote: > Reads at quorum in dc3 will involve dc1 and dc2 as they will require a > response from

How to understand of dynamic snitch update interval?

Hi there, I have a question for dynamic snitch, specifically in reading. For dynamic snitch, it is wrapped with other snitches. For reading, dynamic snitch plays a very important role, as mentioned in this article:

Re: New data center to an existing cassandra cluster

If you’ve repaired at the point you alter keyspace to add the third DC, and you write with quorum, and your RF per DC is the same (for example, 3 in each DC), then you’ll likely get valid read requests, as long as none of the other nodes go down while you rebuild. There are a lot of IFs and

Re: New data center to an existing cassandra cluster

Reads at quorum in dc3 will involve dc1 and dc2 as they will require a response from more than half the replicas throughout the Cluster. If you're using RF=3 in each DC, each read will need at least 5 responses, which DC3 cannot provide on its own. You can have troubles if DC3 has more than half

Re: New data center to an existing cassandra cluster

Yes, it will have issue during the time new nodes are building So it is always advised to use LOCAL_QUORUM instead of QUORUM and LOCAL_ONE instead of ONE On 27 August 2016 at 09:45, laxmikanth sadula wrote: > Hi, > > I'm going to add a new data center DC3 to an

New data center to an existing cassandra cluster

Hi, I'm going to add a new data center DC3 to an existing cassandra cluster which has already 2 data centers DC1 , DC2. The thing I'm worried of is about tables in one keyspace which has QUORUM reads and NOT LOCAL_QUORUM. So while adding a new data centers with auto_bootstrap:false and 'nodetool

Re: Guidelines for configuring Thresholds for Cassandra metrics

I did not claim you had no evidence, only that your statement lacked justification. Again, nuance is important. I was suggesting that blanket statements without the necessary caveats, to the user mailing list, countermanding the defaults without 'justification' (explanation, reasoning) is liable

Re: Guidelines for configuring Thresholds for Cassandra metrics

 I have been trying to get the docs fixed for this for the past 3 months, and there already is a ticket open for changing the defaults. I don't feel like I've had a small amount of evidence here. All observation in the 3 years of work in the field suggests compaction keeps coming up as the

problem with transactions

Hi, Initially, one “if exists” query was not working on cassandra 3.0.8. Its started working after we downgraded to 2.2.7. Now, there are some more “if exists” queries which are not working on cassandra 2.2.7 in some cases. Is there anybody else facing the same problem with transactions? We are