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.

1337 questions
77
votes
6 answers

Make a Docker application write to stdout

I'm deploying a 3rd-party application in compliance with the 12 factor advisory, and one of the points tell that application logs should be printed to stdout/stderr: then clustering software can collect it. However, the application can only write to…
kolypto
  • 10,738
  • 12
  • 51
  • 66
45
votes
2 answers

Redis Cluster: (error) MOVED

I have a Redis cluster with the following nodes: 192.168.0.14:6379 master (slots from 0 to 16383) 192.168.0.15:6379 slave (slots from 0 to 16383) 192.168.0.16:6379 master (without slots) Documentation says that any node can redirect queries to the…
Oleksandr
  • 703
  • 2
  • 10
  • 17
33
votes
2 answers

nginx automatic failover load balancing

I'm using nginx and NginxHttpUpstreamModule for loadbalancing. My config is very simple: upstream lb { server 127.0.0.1:8081; server 127.0.0.1:8082; } server { listen 89; server_name localhost; location / { …
robinmag
  • 453
  • 1
  • 5
  • 8
26
votes
4 answers

How can I pre-sign puppet certificates?

Puppet requires certificates between the client (puppet) being managed and the server (puppetmaster). You can run manually on the client and then go onto the server to sign the certificate, but how do you automate this process for clusters / cloud…
Ranguard
  • 681
  • 7
  • 9
25
votes
15 answers

Cheapest iSCSI SAN for Windows 2008/SQL Server clustering?

Are there any production-quality iSCSI SANs suitable for use with Windows Server 2008/SQL Server for failover clustering? So far, I've only seen Dell's MD3000i, and HP's MSA 2000 (2012i), which both are around $6K with a minimal disk configuration.…
MichaelGG
  • 1,739
  • 8
  • 25
  • 30
24
votes
2 answers

Is it a good idea to store Docker volumes in glusterfs?

I am currently thinking about migrating some of our servers and apps to a coreOS environment. One of the problems I see here is the management of persistent data as coreOS does not handle Docker volumes when moving a container to a new machine.…
Martin
  • 353
  • 1
  • 2
  • 8
23
votes
6 answers

Bidirectional real-time sync of large file tree between two distant linux servers

By large file tree I mean about 200k files, and growing all the time. A relatively small number of files are being changed in any given hour though. By bidirectional I mean that changes may occur on either server and need to be pushed to the other,…
dlo
  • 451
  • 1
  • 4
  • 14
20
votes
4 answers

Are ZFS clustered filesystems possible?

Is it possible to create a ZFS cluster? Or would you need to go the seemingly ugly (to me at least) route of ZFS with UFS formatted pools governed by GlusterFS? The idea is to see if it is possible to expand to Multi-Petabyte distributed store which…
SteveMustafa
  • 419
  • 1
  • 5
  • 11
20
votes
1 answer

Which messaging layer to use, Heartbeat or Corosync?

Just about finished my research into setting up a web server cluster and I'm still undecided as to which messaging layer to use with Pacemaker. The servers I'm using are all Fedora so both layers are available via YUM, both are well documented and…
Jeff Busby
  • 521
  • 1
  • 3
  • 9
16
votes
8 answers

When is the right time to introduce high availability for web site?

When is the right time to introduce high availability for web site? There are many articles on High Availability options. It’s not that obvious however WHEN is the right time to switch from single server to high availability configuration. Please…
Dennis Gorelik
  • 331
  • 2
  • 8
15
votes
4 answers

Managing an application across multiple servers, or PXE vs cfEngine/Chef/Puppet

We have an application that is running on a few (5 or so and will grow) boxes. The hardware is identical in all the machines, and ideally the software would be as well. I have been managing them by hand up until now, and don't want to anymore…
matt
  • 1,112
  • 1
  • 8
  • 18
14
votes
4 answers

Redis cluster: 3 master nodes minimum?

I'm evaluating the cluster capabilities of Redis 3 (I'm using Redis 2 standalone at the moment), so I am reading the info at http://redis.io/topics/cluster-tutorial. In this document I read a very important info: Note that the minimal cluster that…
Mat
  • 1,783
  • 4
  • 22
  • 39
14
votes
3 answers

How does one cluster multiple machines to act as one to run multiple virtual machines on this single-seeming machine?

How does one take multiple computers and make them act as one, such that all their processors and memory are combined now and you are running any application such that yo are running them on a single very fast computer. Such that it can be used to…
user2387
  • 141
  • 1
  • 1
  • 3
14
votes
5 answers

mirrored filesystem across a few servers

I'm looking for a solution to mirror or replicate one directory (or one filesystem) across a few Linux servers. Ideal solution would be one, which permits all servers read-write access. I also want it to me resilient, if one of the servers goes…
vartec
  • 6,137
  • 2
  • 32
  • 49
14
votes
4 answers

Multiple servers acting like a single one with all the hardware?

by now I have 10 servers for hpc, power computing oriented. My users need to launch several processes using qmake. The users are used to work with ubuntu 9.10, and the software from the repositories is switable for them. I've deployed ubuntu 9.10 to…
Marc Riera
  • 1,587
  • 4
  • 21
  • 38
1
2 3
89 90