Questions tagged [cluster]

A computer cluster consists of a set of loosely connected computers that work together so that in many respects they can be viewed as a single system.

A computer cluster consists of a set of loosely connected computers that work together so that in many respects they can be viewed as a single system.

The components of a cluster are usually connected to each other through fast local area networks, each node running its own instance on an operating system. Computer clusters emerged as a result of convergence of a number of computing trends including the availability of low cost microprocessors, high speed networks, and software for high performance distributed computing.

Clusters are usually deployed to improve performance and availability over that of a single computer, while typically being much more cost-effective than single computers of comparable speed or availability.

Computer clusters have a wide range of applicability and deployment, ranging from small business clusters with a handful of nodes to some of the fastest supercomputers in the world such as the K computer.

Source: Wikipedia.

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How to set up Zabbix to monitor SQL Server Failover Active-Passive Cluster?

It should be simple, so it is just most likely my approach being totally off and someone will hopefully prod me into the right direction. We have a Zabbix 2.0.3 server instance set up monitoring a bunch of different servers, but now we need to set…
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How to set up alerts on Ganglia?

How can I set up Ganglia so that I get an email if a machine in the cluster is using, for example, greater than 95% of physical RAM?
Tanmay
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How does a SQL Server Availability Group decide on which secondary will become the new primary when an automatic failover is triggered?

How does a SQL Server Availability Group with multiple synchronous-commit secondary replicas decide on which secondary replica will become the new primary when an automatic failover is triggered? Can't find any information on this in the…
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Pacemaker corosync 2-node with a 3rd for quorum

I'm having trouble figuring out how to configure a 2-node setup with a third simpler one for quorum. It seems to think all the nodes have the capability to act as a full fallback node, when I only I want a quorum with STONITH working sanely for what…
Martti
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Performance of Cluster Shared Volume file copy from SAN

I am hoping someone can help me out with a strange issue. We are running a Microsoft Failover Cluster with Server 2008 R2 and an Equallogic PS4000 SAN. Our main configuration has 2 Dell Poweredge T710 Servers in the cluster. We have CSV and Quorm…
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Prevent iSCSI connection from being terminated early on reboot

I have a clustered Hyper-V environment with four nodes and three PowerVault MD3xxx storage arrays for shared storage. The servers are using standard Ethernet connections for the iSCSI fabric (not HBAs). MPIO is configured via the Dell storage…
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Are there cluster resource schedulers abstraction layers?

I'm writing an application that could potentially be run on any cluster resource scheduler (SGE, LSF or SLURM to name a few of them), using very basic functionalities. I'm wondering if a framework/abstraction layer does exist for interacting with…
nicoulaj
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Converting our budget-strapped dev environment to ESXi - how to maximize availability on the cheap

We've already run through the process of virtualizing our production servers and now we want to do the same with our dev environment. However, our provider took care of all of the ESX host and cluster configuration (SAN, physical switches, host…
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Ganeti and automatic failover

I'm building a simple 2-node cluster with Ganeti+DRBD... What is the recommended way to setup automatic failover? I'm used to Heartbeat, but they say it should be avoided with my setup.
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Tomcat mod_jk cluster skip 404 http status

I am trying Tomcat Clustering with mod_jk for months and so far not so bad but facing a problem during deployment. I am using FarmDeployer to copy and deploy the WAR to other nodes in the cluster but most of the time the WAR is not deployed properly…
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Multiple VPS with mirrored database and filesystem

I've developed interest in VPS clusters lately and it seemed like a great idea to try to set up a multi-VPS setup, which I will describe below. It isn't really meant for production use, but more as an experiment to improve relevant skills and…
zatatatata
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Windows 2008 R2 File Server Cluster vs. DFS

We're currently using 2 Windows 2008 R2 with DFS but discovered some issues with: replication of permissions (permissions are not replicated across DFS members) replication of quota (quota is disk-based) Do these problems exist in clusters?…
FrancisV
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Filesystem redundancy + speed

Looking for some input and if anyone has conquered this problem with a solution they feel confident about. Looking to setup a fault tolerant web environment. So the setup is a few nodes behind a load balancer. Now the web devs can ssh into 1 server…
Mike
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how does VMWare CPU shared (across different Host) in a Cluster?

Example: You have a DRS cluster with 3 Hosts. If i run a test in VM1 which resides in ESX1, needs more CPU it will be allocated from the Cluster (== ESX2) now how this done ? will one of my VM1 process thread will run on ESX2 CPU ?
Leo
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Recommendations for distributed processing/distributed storage systems

At my organization we have a processing and storage system spread across two dozen linux machines that handles over a petabyte of data. The system right now is very ad-hoc; processing automation and data management is handled by a collection of…
Eddie
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