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.

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Tomcat 7.0 Clustering FarmWarDeployer Not working

I'm currently working on a Tomcat Cluster for Q&A, but unfortunatly, it seems that the auto deploy of a war across this cluster is not working at all. I know the cluster is working perfectly ...
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1answer
15 views

How to setup user accounts on a secondary server in High Availability?

Working with two Microsoft SQL 2012 servers in Always On High Availability configuration running on Windows Server 2012 R2. Setup works well and failover is almost flawless. However, the software ...
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1answer
24 views

How does load balancing work for a coreOS cluster?

Preface: I don't know much about load balancing. Say I have a few virtual machines on a cloud service like Amazon, running a few instances of coreOS each. How exactly does load balancing work in ...
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0answers
46 views

vSphere Cluster no failover

I've inherited a 2-node vSphere Cluster (vCenter appliance in the cluster). We recently had one host crash during working hours. My understanding with a vSphere HA Cluster (and like any cluster) when ...
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1answer
1k views

clvmd problems during the RHEV cluster deployment

We are deploying Red Hat Enterprise Virtualization cluster and we faced a problem attempting to start clvmd service after the lvm partition creating. The following has been completed successfully: ...
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1answer
28 views

PBS, adding job - job added, seems that it didnt run at all

First of all, Im very new to clusters and PBS systems. I was told to prepare a simple script (which I did): #PBS -S /bin/bash #PBS -o host_out #PBS -e host_err #PBS -q batch hostname date exit 0 ...
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0answers
81 views

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 enviroment. One of the problems I see here is the management of persistent data as coreos does not handle Docker ...
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2answers
2k views

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 ...
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0answers
18 views

corosync is not in sync

Could you please help out show me how to form a cluster? corosync & pacemaker are used. two nodes rac0 ip 192.168.0.140 & rac1 ip 192.168.0.142 They are not shown in each other. They are ...
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1answer
23 views

How to monitor MariaDB Galera cluster status from command line

I know to check the Galera cluster status, the command that should be used after login to the mysql client is: SHOW STATUS LIKE 'wsrep%'; but, how to get the output directly from the command line? ...
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2answers
1k views

Heavy write to Galera cluster - table locked, cluster practically unusable

I set up Galera Cluster on 3 nodes. It works perfectly for reading data. I have done simple application to make some test on the cluster. Unfortunately I have to say that the Cluster fails totally ...
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1answer
32 views

Tomcat does not replicate session attributes

I am struggling with configuration of session replication in Tomcat cluster. Ramki's articles about Tomcat Clustering helped me a lot. Load balancing and sticky session works well. SessionIDs are ...
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0answers
69 views

Python libraries slow to load from NFS mount point

Several of our computers are diskless, and they load their Python libraries from an NFS mount point across the network. This means it can take up to three minutes to start up a Python process that ...
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1answer
238 views

What cluster management software does there exist for Windows, except for MS HPC Server? [closed]

Do there exist any open-source solutions? Perhaps, cheaper commercial ones? I'm surprised that googling does not yield anything meaningful for me.
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1answer
4k views

JBoss 7.1.1 Clustering, JBAS014775:New missing/unsatisfied dependencies

I am following https://docs.jboss.org/author/display/AS71/AS7+Cluster+Howto I managed to get 2 servers running. One slave. One master. I managed to get to "Dry Run" I got: [Host Controller] ...
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1answer
63 views

Monitoring a cluster storage on Microsoft Windows Server 2012 R2 HyperV via SNMP

As a part of my task of monitoring our whole server environment it is planned to check the cluster storage (cluster shared volume, csv) of our HyperV cluster with Check_MK/Nagios3. Exactly needed is ...
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1answer
75 views

Keepalived + Haproxy performance, apache or nginx? [duplicate]

I have a question about Keepalived + Haproxy. At work I am assigned to deploy a redundant web server with Keepalived and Haproxy. Our setup at the moment is as follows: Apache (as load balancer) + ...
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0answers
38 views

Single node SQL Server 2014 cluster at DR environment

We are setting up a new Disaster Recovery environment. On Production we have SQL Server cluster with two nodes. For DR we decided that one node should be enough. The plan is to add the second node ...
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1answer
1k views

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 ...
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0answers
21 views

Is it possible to prevent pcs/dlm/crm from fencing the node when it fails?

Is it possible to prevent pcs/dlm/crm from fencing the node when it fails? I use cluster only to be able to build GFS2 storage, and there's my own way of avoiding split-brain. So I do not need things ...
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1answer
903 views

What's the best way to manage product images in a Magento Cluster?

I'm running Magento CE on multiple web node. The Admin Backend is always running on the same server, so all the images are uploaded on this server. On my
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6answers
4k views

alternative to Clusterssh for managing multiple SSH server

Is there any alternative to Clusterssh,pssh etc? to manage multiple ssh based servers through one interface? one weakness in Clusterssh is that my servers use key based authentication, with ...
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1answer
24 views

Tomcat Clustering With Apache-[warn] proxy: No protocol handler was valid for the URL /. If you are using a DSO version of mod_proxy

I am new to apache and tomcat, and trying to implement clustering with mod_proxy and able get run multiple tomcat instances but got stuck. Here is my config: httpd.conf: LoadModule proxy_module ...
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0answers
5 views

SQL alwaysON and WSFC

I have a WSFC configured on 2 (hardware)nodes with SQL AlwaysOn group. The problem is, if the node Where I have created the cluster goes down the cluster is not available for second node and here ...
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1answer
44 views

Setting up Windows Server Failover Clustering in SoftLayer

I'm trying to create a Windows Server Failover Cluster. I've already create Active Directory successfully. I'm currently at this stage: On the screenshot, the blurred place has subnet/network id, ...
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1answer
47 views

Merge Live VMware hosts into existing vcenter

We currently have 3 VMware hosts, all running ESXi 4.1. They are all HP DL380 G7's, two of them having dual Xeon E5620 cpus with 96GB RAM, and the third having dual Xeon E5645 cpus and 64GB RAN. The ...
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1answer
164 views

Split brain on DRBD and Pacemaker cluster

I want to put into your consideration the following situation that is currently happening on our active-passive cluster (DRBD, Pacemaker, Corosync, PostgreSQL) OS: Ubuntu server 14.04 x64 DRBD: 8.4 ...
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1answer
173 views

apache proxypassreverse ServerName not working

I have a secondary development wordpress site. (Centos 6.6 x86 ,LAMP) Since the size of the site is growing. (300GB+). Now I divide it into 3 server. domain: www.example.com server1 46.192.22.01 ...
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1answer
43 views

Microsoft windows 2012 clustering

I have 2 hardware servers with Microsoft windows server 2012 R2 standard. One of them is our production server and running on it our application. I was thinking to configure the second in a cluster to ...
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1answer
42 views

Cluster computing over Wifi

I was recently reading about Cluster Computing and how it used Ethernet as preferred interface. My question is why not use WiFi? It has a 300Mbps (802.11n) throughput and without all the wiring ...
0
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1answer
32 views

2012R2 Cluster - Add host without downtime

Essentially just want to confirm my current thoughts - have a 3-node 2012R2 Cluster. We are replacing two of the hosts. At the point when you add a new host to the cluster and run the validation, the ...
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1answer
2k views

Ejabberd not allowing registration from client

I've got an ejabber cluster setup. When trying to register a user with a client (say Adium) I'm getting a 503: Service Unavailable error. I'm running ejabberd 2.1.x The log shows this: ...
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42 views

Best scenario for global data replication and distribution between multiple servers [closed]

I need to store and serve about 30TB of data (for now) and the number will increase pretty fast. I also have to keep costs low, so I will have servers with no RAID at all. Instead data should be ...
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0answers
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Are there any tools/APIs to check consistency of a windows cluster?

Things to be checked: Directory structures (recursive, with any attributes and properties) Configuration (equiv and partial conf, format specific or generic, with regex) Registry (presence of keys, ...
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3answers
7k views

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 ...
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0answers
18 views

Deploy from Eclipse to Tomcat cluster

I've the following cluster configuration in server.xml on each server (there are two): <Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"> <Deployer ...
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0answers
35 views

Watchguard HA Cluster Issue

I am trying to setup a Watchguard Firecluster in our rack and am having issues with the setup. We have two Ethernet up links provided by the Data center that go to their VRRP/HSRP configured routers ...
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0answers
23 views

Diskless cluster using Perceus: nodes don't boot

I'm constructing diskless cluster using Perceus. Few days ago, I succeed Clustering using Perceus. Nodes are booted well and i can use ssh to nodes. Even i run mpi program. Today, I tried to ...
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1answer
41 views

How can I create a small cluster and include non dedicated servers?

We want to set up a small cluster, witch will store some databases and testing services at first. The cluster will initially launched on 8 dedicated servers (HP G3/G5). 6 of the servers in in the same ...
3
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1answer
94 views

What is the proper way to shutdown an iSCSI target with connected clients?

iSCSI with two DRBD primary nodes is a bad idea to use if the two paths get concurrent write requests. But I am thinking about using this idea as backend storage for an ESXi 5.5U2 host. I already did ...
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2answers
116 views

Failover pacemaker cluster with two network interfaces?

So, i have two test servers in one vlan. srv1 eth1 10.10.10.11 eth2 10.20.10.11 srv2 eth1 10.10.10.12 eth2 10.20.10.12 Cluster VIP - 10.10.10.100 Corosync config with two interfaces: ...
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1answer
85 views

Windows cluster has lost or discarded the CLUSDB

Both nodes of a two node windows failover cluster on 2008R2 have lost the CLUSDB file. I think this happened because an inexperienced admin came to a cluster with a reserved disk issue and ...
2
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3answers
860 views

Can you explain why I shouldn't serve PHP off Gluster?

There's a good chance that I'll end up running Drupal on several front-end nodes over the next six months, and I'd like to know if there is a good reason not to have a single instance of Drupal stored ...
2
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2answers
77 views

WildFly 8.1 domain mode with shared properties

I'm trying to configure a WildFly 8.1 cluster and I have not found any satisfying answer for sharing common property files. In standalone mode I've added some property files to the configuration ...
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0answers
198 views

monitor of systemd resource with pacemaker & corosync returns “not running” when cloned while it is

The setup: - OS: CentOS 7, latest versions op Corosync, Pacemaker & PCS - two node active/active cluster with a virtual IP - on both nodes Exim is running for outoging mail (SMTP), nothing special ...
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0answers
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Configuring Proxmox Cluster Storage

We are configuring proxmox on our servers at two locations each location has; 1 x hp c7000 enclosures with 16 blades 1 x hp proliant dl585 We also plan to add a 24TB SAN to each location. We are ...
7
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1answer
2k views

Does CoreOS have a cluster aware job scheduler?

Ive been checking out CoreOS and I'm impressed. Before I found CoreOS I was looking at the Mesos/Marathon/Chronos stack as a "cluster kernel". Given the following comparison: init.d == ...
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2answers
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Graphite/Carbon cluster returning incomplete data

Trying to setup a Graphite/Carbon cluster. I have an elastic load balancer that directs traffic between two nodes in my cluster, each with one web app, relay, and cache. In this example, I sent 1000 ...
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1answer
39 views

Exploit monetarily a large unused cluster [closed]

At work we have a 200 core unused cluster, most of the researchers working here just left and nowadays almost nobody uses it. We would take advantage of it. Previously somebody asked it how to exploit ...
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1answer
30 views

why configure cluster nodes to reboot when out of memory

I have access to a research HPC cluster which is configured so that if your job tries to use more memory than the node has available the node crashes and automatically reboots. This appears to be ...