A cluster consists of a group of computers connected so that in many respects they can be viewed as a single system.

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MySQL high availability, failover and replication with Latency

We are in the process of implementing a new CMS (Drupal 6.x) that runs on MySQL. We have two data centers -- primary and secondary -- with known latency between them. We're unsure which version of ...
62
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5answers
12k views

Why can't RDBM's cluster the way NoSQL does?

One of the big plusses for nosql DBMS is that they can cluster more easily. Supposedly with NoSQL you can create hundreds of cheap machines that store different pieces of data and query it all at ...
2
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2answers
6k views

Creating High Availability Cluster with PostgreSQL

I am new to database design. I have a task to create a high-availability cluster. I Googled a lot, however I haven't found any good way to do this on PostgreSQL. Where should I start and what are ...
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3answers
2k views

Does Change Data Capture (CDC) work in a SQL Server 2012 AlwaysOn Failover Cluster Instances setup?

Does Change Data Capture (CDC) work in a SQL Server 2012 AlwaysOn Failover Cluster Instances setup? There would be two nodes in the AlwaysOn Failover Cluster Instances setup and two Domain ...
35
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4answers
22k views

Clustering vs. transactional replication vs. availability groups

Assuming you need to make sure your application that relies on SQL Server 2012 as its database backend is available around the clock, even if one server machine fails. As a developer and not a DBA, I ...
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3answers
4k views

How? SQL Cluster with multiple active nodes (not failover)

I'm building a new SQL 2008 R2 (Enterprise) Cluster that is backed by an EqualLogic iSCSI SAN. Instead of building a failover cluster (which I have done), I would instead like to setup several nodes ...
4
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1answer
3k views

Multiple IPs registered for listener when using AlwaysOn AGs w/ multi-subnet clustering

We are testing AlwaysOn Availability Groups on a WSFC multi-subnet cluster and using dynamic DNS registration. Our issue is that sometimes the IP for the Availability Group Listener (AGL) in the ...
4
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1answer
264 views

How can I achieve clustering of rows without the exclusive lock and logging overhead of the `cluster` command?

The CLUSTER command on a big table can take a long time, and blocks both reads and writes to the table while it runs. I don't need the data in my table to be strictly sorted in index order, I just ...
3
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1answer
68 views

Traditional failover clustering vs. Availability Groups

I'm looking into Availability Groups to see if i can benefit from them, but I struggle to understand if I can or not. Today, we are running a traditional failover cluster with around 150 databases. ...
2
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2answers
857 views

Experience using ScaleArc in test or production?

Has anyone had any experience using ScaleArc? My CTO has asked my thoughts on it, and I have seen no information out there regarding real-world experiences.
1
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3answers
278 views

9 node percona xtradb cluster

We are looking to launch a 9 node percona xtradb cluster on Amazon where each ec2 node uses 20k iops disks. I was afraid if a 9 node cluster will work and mostly what I see is 3 node clusters. We ...
1
vote
1answer
261 views

SQL Server 2012 Cluster Service pack 3 fail to failover node

Roughly a year ago, i had this problem with an 2008R2 cluster. I asked about it here, but i didn't grab enough logs in the process. And now i have the same problem on my 2012 failover cluster. So i'm ...
5
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3answers
3k views

Port number change

We are planning on setting a static port for SQL Server 2005/2008 failover clustering. Any guide on what port to choose/select for 4 nodes of each cluster?(Active/Active) I am also thinking some ...
5
votes
1answer
9k views

Problem adding a new node to a SQL Server 2012 Failover Cluster

I tried to add a new node to SQL Server (2012 Standard) Failover, that is already installed on another node in Windows2012 Failover Cluster I have an issue with non editable field wiht input for SQL ...
2
votes
1answer
665 views

AlwaysOn Availability Groups: Confusion with some concepts

In Sql Server 2012, I am trying to install Failover Clustering to configure AlwaysOn Availability Groups. When I run Cluster Validation test wizard, it comes back with a lot of errors. One of them ...
2
votes
1answer
425 views

grastate.dat with seqno -1 on a healthy cluster. Why?

We use those versions: # rpm -qa | egrep '(galera|maria)' mariadb-libs-5.5.41-2.el7_0.x86_64 mariadb-galera-common-5.5.40-6.el7ost.x86_64 mariadb-galera-server-5.5.40-6.el7ost.x86_64 mariadb-5.5.41-2....
0
votes
0answers
40 views

Log shipping with active active cluster configuration

Scenario: We are planning to configure active active cluster for our SQL Server. Both will be having separate instances(A instance on node 1, B instance on node 2). 'A' instance will have Production ...
0
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1answer
198 views

unable to connect to specific instance ORacle RAC

I did several operations by connecting successfully to all 4 instances but suddenly during one of the jobs, it failed with a TNS error. I checked the connect from SQL and one of the nodes is giving an ...