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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Managing a Linux cluster

I'm interested in learning about tools and techniques used to manage many Linux machines. (That is, deploying and maintaining updates.) One way that I thought of to do this is write a Bash script that uploads another script to the servers and…
razor
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Is Tomcat Shared Session / Cluster between two machine possible?

I have a setup of several Tomcat servers distributed between a few servers, all running the same thing. Apache is on top of Apache and a loadbalancer in front of the Apache servers. I want to cluster the Tomcats using Shared Session to minimize…
Snorri
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(*nix) Cloud/cluster solutions for scalable web-services

I'm going to build a high-performance web service. It should use a database (or any other storage system), some processing language (either scripting or not), and a web-server daemon. The system should be distributed to a large amount of servers so…
kolypto
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Auditd in a PCI-DSS-compliant Linux cluster

I'm familiar with some of the more common ways of configuring a Linux server to be compliant with PCI-DSS 3.2, at least to the requirements of SAQ A. A common concern is requirement 8.5 which requires that: Generic user IDs and accounts are…
richard
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Windows 2012 R2 Hyper-V cluster without shared hardware

I have several servers with local SATA/SAS RAID arrays. I would like to run there virtual machines with some level of automated failover - sync VM to secondary node in 1 minute interval and automated start when primary node died at least. I've…
Jan Zahradník
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Redis/Sentinel cluster failover results in "failover-abort-not-elected master"

I have a 2 node Redis cluster set-up. [master] 192.168.56.102: Redis Master (:6379), Redis Slave (:6380), Sentinel(:26379), Sentinel#2(:26380) [rescue] 192.168.56.103: Redis Master (:6379), Redis Slave (:6380), Sentinel(:26379) Each slave instance…
sm0ke21
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Multiple Postgres Servers (one writer, multiple reader) with Shared Disk

Here's the scenario: One shard disk (Gluster) Multiple Postgres servers Requirements: Use the shared disk to store the database files Use a configuration which provide maximum efficiency Findings so far, It's possible to use a shared disk to…
Rad
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glassfish cluster fail at start

I got a problem trying to set a cluster up. I'm gonna describe detailed configuration(since I couldn't find a cluster example made on two different pcs, all of them were made on one localhost): 3 ubuntu virtual machines: 1 domain administrator and 2…
Marco Aviles
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mount.ocfs2: Transport endpoint is not connected while mounting...?

I have replaced a dead node that was running in dual-primary mode with OCFS2. All the steps work: /proc/drbd version: 8.3.13 (api:88/proto:86-96) GIT-hash: 83ca112086600faacab2f157bc5a9324f7bd7f77 build by mockbuild@builder10.centos.org, 2012-05-07…
quanta
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MySQL Clustering

I run a mysql server that hosts around 50Gb of data (primarily for around 250 websites), and am wondering what my options are for setting up a redundant MySQL cluster? The primary purpose would be that I could take one server down for maintenance…
Brent
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csync2 ERROR: Connection to remote host failed

I was unable to find any articles to answer this question, so my best bet was to post this here: Scenario We have 2x application servers in production hosting a PHP website and I would like some folders to be syncronized between the 2, the same was…
Emil Salama
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Encrypted storage for clustered MySQL

I have a requirement to provide a highly available MySQL database with encryption-at-rest on a 2.6.32 linux kernel. The 'highly available' part isn't that hard, but the 'with encryption-at-rest' is proving to be a challenge when used in combination…
sysadmin1138
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What makes Lustre faster and more scalable than NFS?

I have read in various places (e.g. here and here) that NFS' I/O performance does not scale, while Lustre's does, and that Lustre can deliver better I/O rates in general. There seem to be various architectural differences between the two, but I…
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SQL Server 2008 R2 cluster, "available storage" shows "offline"

I've installed a SQL Server 2008 R2 cluster and I found the resource group "available storage" shows "offline" status. What does it mean? It seems I can't take it online. I tried to use the cluster resource command and it shows that there seems no…
Just a learner
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Upgrading ubuntu release on a cluster of servers

I have a cluster of about 50 ubuntu nodes which are currently running maverick release. I'd like to upgrade them to oneiric, but I'm having a difficulty choosing the right tools. I know ubuntu has the 'unattended-upgrade' utility, but it's only…
Akarot
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