All Questions
Tagged with database-replication cassandra
27 questions
1
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1
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67
views
How can I sync replicas with each other?
I have two replicas for my main cassandra server. Both the replicas are not in sync with the main server. This happened because the replica servers were running into errors cause by commit logs for 3 ...
- 11
0
votes
1
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108
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Error in ReadRepairStage Cassandra in system.log
Currently we are seeing:
ERROR [ReadRepairStage:896014] CassandraDaemon.java:228 - Exception in thread Thread[ReadRepairStage:896014,5,main]
org.apache.cassandra.exceptions.ReadTimeoutException: ...
- 11
0
votes
1
answer
2k
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Benefits of leader/follower over masterless
I'm learning about replication strategies and wondering the pros of cassandra (masterless) over mongo (leader/follower).
From what I've read, they both scale writes the same because writes writes in ...
- 13
0
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1
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115
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How to do LOAD BALANCING and manage REPLICATION in our following PHP-PDO Configuration Code with Cassandra Database?
According to Wikipedia, Load balancing refers to the process of distributing a set of tasks over a set of resources, with the aim of making their overall processing more efficient.
So, wanting to use ...
user7962781
1
vote
1
answer
8k
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Cassandra :NoHostAvailableException: All host(s) tried for query failed
I'm repplication the data from on simplestrategy Cassandra's DB to another one. They have the same keyspace's structure. However, when I ran the command sstableloader --nodes appeared the error below. ...
- 1,157
0
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1
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116
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Why cassandra nodes responsible for (N-1) ranges only?
So I was reading the Cassandra paper. In the section 5.2 (replication), below is mentioned.
All nodes on joining the cluster contact the leader who tells
them for what ranges they are replicas for ...
- 388
0
votes
1
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218
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MongoDB to other DB syncing
we are planning to continuously sync data a collection from MongoDB to another database (in this case Cassandra).
I'm thinking of listening to the mongo-oplog then push those changes to Cassandra. It'...
- 93
1
vote
2
answers
294
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Cassandra LOCAL_QUORUM is waiting for remote datacenter responses
We have a 2 datacenters ( One in EU and one in US ) cluster with 4 nodes each deployed in AWS.
The nodes are separated in 3 racks ( Availability zones ) each.
In the cluster we have a keyspace test ...
- 452
2
votes
1
answer
91
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Cassandra EC2Snitch for Mutli Region Distributions
Ec2MultiRegionSnitch was made I assume because a few years back AWS did not support VPC peering. With the current VPC peering capabilities of AWS, we can peer two regions and set up cassandra in both ...
- 452
1
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2
answers
2k
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Cassandra Replication in NetworkTopologyStrategy
I've just started learning about Cassandra. I have a doubt in NetworkTopologyStrategy. So as we know the nodes in Cassandra is divided based on the hash value of the partition keys. If so during a ...
3
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1
answer
137
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Cassandra: Shipping Disk to New DC in order to sync 50TB of data
We're adding a new datacenter to our Cassandra cluster. Currently, we have a 15-node DC with RF=3 resulting in about 50TB~ of data.
We are adding another datacenter in a different country and we want ...
- 318
0
votes
1
answer
58
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Maintaining RF when node fails
Does Cassandra maintains RF when a node goes down. For e.g. if number of nodes is 5 and RF is 2 then when a single node goes down, does the remaining replica copies it's data to some other node to ...
- 1,750
3
votes
2
answers
582
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Eventual consistency in RDBMS (Oracle)
I understand RDBMS databases like Oracle are not really meant for eventual consistency. But is it technically not feasible to customize oracle to follow eventual consistency model (say like what ...
- 148
4
votes
2
answers
763
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One way replication between Cassandra data centres
We are proposing Cassandra to be implemented as a database backend for a large archiving solution (a large number of writes compared to reads). We are looking for inputs on Cassandra's replication and ...
2
votes
1
answer
3k
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How to enable read only cassandra replication?
Is it possible to do Cassandra data replication into another server instance to run read only data operations on it? As we have explored SAN and it become more hardware expensive
Note:
1. I am not ...
- 69