Multi DC setup

I am trying to understand multi DC setup for cassandra. As I understand, in this setup, replicas exists in same cluster ring, but physically nodes are distributed across DCs. Is this correct? I have two different cluster rings in two DCs, and want to replicate data bidirectionally. They both have

Multi DC setup question

Hi All, We are setting up another Data Center and have the following question: 6 nodes in each DC Cassandra cluster. All key spaces have an RF of 3 Our scenario is Apps node connect to Cassandra cluster using LOCAL_QUORUM consistency. We want to ensure that If 5 nodes out of the 6 are a

Re: Multi DC setup

pardon occasional typos as I respond @ the speed of thought / On Oct 10, 2011 10:09 PM, "Cassa L" wrote: I am trying to understand multi DC setup for cassandra. As I understand, in this setup, replicas exists in same cluster ring, but physically nodes are distribu

Re: Multi DC setup

re split-brain > for a while. > > /*** > sent from my android...please pardon occasional typos as I respond @ the > speed of thought > / > > On Oct 10, 2011 10:09 PM, "Cassa L" wrote: > > I am trying to understand mu

Re: Multi DC setup

> We already have two separate rings. Idea of bidirectional sync is, if one > ring is down, we can still send the traffic to other ring. When original > cluster comes back, it will pick up the data from available cluster. I'm not > sure if it makes sense to have separate rings or combine these two

Re: Multi DC setup

On Tue, Oct 11, 2011 at 2:36 AM, Peter Schuller wrote: > Google/check wiki/read docs about NetworkTopologyStrategy and > PropertyFileSnitch. I don't have a good link to multi-dc off hand > (anyone got a good link to suggest that goes through this?). http://www.datastax.com/docs/0.8/cluster_archit

Re: Multi DC setup

We already have two separate rings. Idea of bidirectional sync is, if one ring is down, we can still send the traffic to other ring. When original cluster comes back, it will pick up the data from available cluster. I'm not sure if it makes sense to have separate rings or combine these two rings

Multi DC setup for analytics

Hello, We are using cassandra 2.0.17 and have two logical DC having different Keyspaces but both having same logical name DC1. we want to setup another cassandra cluster for analytics which should get data from both the above DC. if we setup the new DC with name DC2 and follow the steps https://

Re: Multi DC setup question

I'm AFK, but you might be able to query the system.peers table to see which nodes are up. Cheers, Jens Den tis 28 juni 2016 06:44Charulata Sharma (charshar) skrev: > Hi All, > >We are setting up another Data Center and have the following > question: > > 6 nodes in each DC Cassandra clus

Re: Multi DC setup for analytics

Yes. Here are the steps. You will have to change the DC Names first. DC1 and DC2 would be independent clusters. Create a new DC, DC3 and include these two DC's on DC3. This should work well. On Thu, Mar 17, 2016 at 11:03 PM, Clint Martin < clintlmar...@coolfiretechnologies.com> wrote: > When y

Re: Multi DC setup for analytics

When you say you have two logical DC both with the same name are you saying that you have two clusters of servers both with the same DC name, nether of which currently talk to each other? IE they are two separate rings? Or do you mean that you have two keyspaces in one cluster? Or? Clint On Mar

Re: Multi DC setup for analytics

Hey Clint, we have two separate rings which don't talk to each other but both having the same DC name "DCX". @Raja, We had already gone towards the path you suggested. thanks all anishek On Fri, Mar 18, 2016 at 8:01 AM, Reddy Raja wrote: > Yes. Here are the steps. > You will have to change t

Re: Multi DC setup for analytics

Hey Guys, We did the necessary changes and were trying to get this back on track, but hit another wall, we have two Clusters in Different DC ( DC1 and DC2) with cluster names ( CLUSTER_1, CLUSTER_2) we want to have a common analytics cluster in DC3 with cluster name (CLUSTER_3). -- looks like th

Re: Multi DC setup for analytics

I'm jumping into this thread late, so sorry if this has been covered before. But am I correct in reading that you have two different Cassandra rings, not talking to each other at all, and you want to have a shared DC with a third Cassandra ring? I'm not sure what you want to do is possible. If I

Re: Multi DC setup for analytics

Hey Bryan, Thanks for the info, we inferred as much, currently the only other thing we were trying were trying to start two separate instances in Analytics cluster on same set of machines to talk to respective individual DC's but within 2 mins dropped that as we will have to change ports on atlas

Re: Multi DC setup for analytics

Anishek, AFAIK you can not have clusters "overlap" each oder. Just an idea: Try to address it as an sstable restore. http://docs.datastax.com/en/cassandra/2.0/cassandra/operations/ops_snapshot_restore_new_cluster.html What I would try to do (not tested!): - create a logical DC in each cluster (

question on multi DC setup and LWT's

HI Guys, Lets say I have 2 DC's and I have 3 node cluster on each DC and one replica on each DC. I would like to maintain Strong consistency and high availability so 1) First of all, How do I even set up one replica on each DC? 2) what should my read and write consistent levels be when I am using

Monitoring replication lag/latency in multi DC setup

Hi, We have multi DC Cassandra ring with 2 DCs setup. We use LOCAL_QUORUM for writes and reads. The network we have seen between the DC is sometimes flaky lasting few minutes to few 10 of minutes. I wanted to know what is the best way to measure/monitor either the lag or replication latency be

Replication issue with Multi DC setup in cassandra

Hello, I am tying to find a way to PREVENT just one of my keyspaces to not sync to the other datacenter. I have 2 datacenters setup this way : Datacenter: DC:4.4.4.4 == Status=Up/Down |/ State=Normal/Leaving/Joining/Moving -- Address Load Tokens Owns (effecti

Re: Monitoring replication lag/latency in multi DC setup

As far as I know Cassandra doesn't use internal queueing mechanism specific to replication. Cassandra sends the write the remote DC and after that it's upto the tcp/ip stack to deal with buffering. If requests starts to timeout Cassandra would use HH upto certain time. For longer outage you would h

Re: Monitoring replication lag/latency in multi DC setup

Thanks for the quick reply, Mohit.Can we measure/monitor the size of Hinted Handoffs? Would it be a good enough indicator of my back log? Although we know when a network is flaky, we are interested in knowing how much data is piling up in local DC that needs to be transferred. Greatly apprec

Re: Monitoring replication lag/latency in multi DC setup

Cassandra exposes lot of metrics through Jconsole. You might be able to get some information from Jconsole. On Wed, Sep 5, 2012 at 8:47 PM, Venkat Rama wrote: > Thanks for the quick reply, Mohit.Can we measure/monitor the size of > Hinted Handoffs? Would it be a good enough indicator of my b

Re: Monitoring replication lag/latency in multi DC setup

Is there a specific metric you can recommend? VR On Wed, Sep 5, 2012 at 9:19 PM, Mohit Anchlia wrote: > Cassandra exposes lot of metrics through Jconsole. You might be able to > get some information from Jconsole. > > > On Wed, Sep 5, 2012 at 8:47 PM, Venkat Rama wrote: > >> Thanks for the quick

Re: Monitoring replication lag/latency in multi DC setup

> Is there a specific metric you can recommend? the not entirely correct but very lightweight approach would be to look at the size of the HintsColumnFamily in the system KS. If you want an exact number use the functions on the HH MBean https://github.com/apache/cassandra/blob/trunk/src/java/

Re: Replication issue with Multi DC setup in cassandra

Do you see data on other DC or just directory structure? Directory structure would populate because it is DDL but inserts shouldn’t populate, ideally. > On May 16, 2017, at 3:19 PM, suraj pasuparthy > wrote: > > elp me fig

Re: Replication issue with Multi DC setup in cassandra

So i though the same, I see the data via the CQLSH in both the datacenters. consistency is set to LQ thanks -Suraj On Tue, May 16, 2017 at 2:19 PM, Nitan Kainth wrote: > Do you see data on other DC or just directory structure? Directory > structure would populate because it is DDL but inserts s

Re: Replication issue with Multi DC setup in cassandra

check for datafiles on filesystem in both DCs. > On May 16, 2017, at 4:42 PM, suraj pasuparthy > wrote: > > So i though the same, > I see the data via the CQLSH in both the datacenters. consistency is set to LQ > > thanks > -Suraj > > On Tue, May 16, 2017 at 2:19 PM, Nitan Kainth

Re: Replication issue with Multi DC setup in cassandra

Yes is see them in the datacenter's data directories.. infact i see then even after i bring down the interface between the 2 DC's which further confirms that a local copy is maintained in the DC that was not configured in the strategy .. its quite important that we block the info for this keyspace

Re: Replication issue with Multi DC setup in cassandra

Strange. Anybody else might share something more important. Sent from my iPhone > On May 16, 2017, at 5:23 PM, suraj pasuparthy > wrote: > > Yes is see them in the datacenter's data directories.. infact i see then even > after i bring down the interface between the 2 DC's which further confir

Re: Replication issue with Multi DC setup in cassandra

Did you run `nodetool repair` after changing the keyspace? (not sure if it makes sense though) 2017-05-16 19:52 GMT-03:00 Nitan Kainth : > Strange. Anybody else might share something more important. > > Sent from my iPhone > > On May 16, 2017, at 5:23 PM, suraj pasuparthy > wrote: > > Yes is see

Re: Replication issue with Multi DC setup in cassandra

May I inquire if your configuration is actually data center aware? Do you understand the difference between LQ and replication? *Daemeon C.M. ReiydelleUSA (+1) 415.501.0198London (+44) (0) 20 8144 9872* *“All men dream, but not equally. Those who dream by night in the dusty recesses of their

Re: Replication issue with Multi DC setup in cassandra

Run *nodetool cleanup* on the *4.4.4.5* DC node(s). Changing network topology does not *remove* data - it's a manual task. But it should prevent it from replicating over to the undesired DC. Also make sure your LoadBalancingStrategy is set to DCAwareRoundRobinPolicy, with *4.4.4.4* DC set as the

Re: Replication issue with Multi DC setup in cassandra

Cqlsh looks at the cluster, not node “All men dream, but not equally. Those who dream by night in the dusty recesses of their minds wake up in the day to find it was vanity, but the dreamers of the day are dangerous men, for they may act their dreams with open eyes, to make it possible.” — T.E. La

Issues during Multi-DC setup across AWS regions + VPC setup

We are trying to add new data center in us-east. Servers in each DC are running inside VPC. We currently have a cluster in us-west and all servers are running 2.0.7. The two DCs are talking via VPN. listen_address and broadcast_address have private ip. Our endpoint_snitch is GossipingPropertyFileSn