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 make AD highly available for applications that use it as an LDAP service

Our situation We currently have many web applications that use LDAP for authentication. For this, we point the web application to one of our AD domain controllers using the LDAPS port (636). When we have to update the Domain Controller, this has…
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How do Active Directory domain joined computers (native MS Windows or Linux with winbind) determine the closest password server?

How do Active Directory domain joined computers (native MS Windows or Linux with winbind) determine the closest password server? This question implies a cluster with 2+ Active Directory servers in different locations. On Windows there is no apparent…
Alex
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How good is failover of the iSCSI target on a two-node linux san?

I'm evaluating the possibility to use two off the shelf servers to build a cheap iSCSI redundant SAN. The idea is to run linux, pacemaker, and an iSCSI target - something like the SAN Active-Passive on linux-ha-examples. The same page scares me a…
Luke404
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High Availability NFS Server (Heartbeat/DRBD) long hang on clients when takeover occurs

We have a High Availability NFS environment using DRBD, heartbeat and nfs exposed to clients (Simular to the following https://help.ubuntu.com/community/HighlyAvailableNFS ). This seems to be a rather common and well supported method of doing HA…
leenix
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Disaster Recovery Planning, tower or rack?

I'm working on this project to develop a system with centralized information regarding emergencies delivered via open Wi-Fi on a small city. I'm from Chile, so we thought of this system to work especially when an earthquake strikes the city (just…
user78442
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SQL Server clustering options

Can anyone give an high-level overview of the options available for SQL Server clustering, their pros and cons? Is it better to use Microsoft Clustering services or SQL Server native clustering? Does that choice even apply to the latest SQL Server…
Tomalak
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How to reserve complete nodes on Sun Grid Engine?

How do you use SGE to reserve complete nodes on a cluster? I don't want 2 processors from one machine, 3 processors from another, and so on. I have a quadcore cluster and I want to reserve 4 complete machines, each having 4 slots. I cannot just…
artif
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High Availability for SSL Web Site

One of our web server clusters serves a moderate number of busy e-commerce applications. At present, each site lives on a specific web server and has a hot-spare copy mirrored to another web server in the cluster. If a server fails, there is a…
Justin Scott
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Need suggestions for a R/W distributed file system for a webserver cluster running Apache+PHP

In the last few months, I've been trying to find the best way to share the content of multiple websites across multiple web servers (12+) all running Apache+PHP. One of the biggest challenge I face is that we need to be able to read and write to the…
Pierre
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what is gen_clust_index used for in mysql?

It seems I have a deadlock in mysql (running innodb) that's due in part to a lock on gen_clust_index, however, this isn't a table that I've created. So... what's the short and sweet description of gen_clust_index and it's use and purpose in mysql.
Langley
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Minimum hardware requirements of a loadbalancer?

I'm going to use a FreeBSD system as a loadbalancer which routes 1gbps public traffic to back-end webserver cluster. What are the minimum hardware specs for this job? Thanks.
Jeff
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Skip over intermediate server via SSH

I just got hired to work in a lab with a big 'ol linux cluster. I'm a mac/windows guy, so I'm still trying to figure out how to navigate around using a 'nix command line. So far I haven't run into any actual problems, but I have encountered about…
tel
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Linux stretch cluster: MD replication, DRBD or Veritas?

For the moment there's a lot of choices for setting up a Linux cluster. For cluster manager: you can use Red Hat Cluster manager, Pacemaker or Veritas Cluster Server. The first one has the most momentum, the second one comes by default with RH…
PieterB
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Is Clustering really = High Availability?

These days clustering is becoming synonymous to high availability. As an enterprise architect I have to shake my head in disbelief. IMHO, clustering can be a component of HA but is far from being HA in itself. I'm always used to approaching HA as a…
G33kKahuna
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VMware Virtual Machine Clustered Filesystem Setup

The situation is: I am running VMware ESX 3.5 (3 ESX Hosts w/ vCenter Server in a Cluster); I need five Virtual Machines to read from the same disk running a clustered file system; I cannot replicate data for each Virtual Machine due to capacity;…
Antitribu
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