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.

learn more… | top users | synonyms (1)

0
votes
1answer
136 views

Cluster vs Virtualization [closed]

I’m working in releasing a video hosting website (files are from webcams) Each file size will be less than 1 mb. I would like to be able to easily extend my storage capacity and have high ...
0
votes
1answer
52 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 ...
0
votes
1answer
257 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 ...
0
votes
0answers
97 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 ...
11
votes
2answers
3k 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 ...
1
vote
0answers
418 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 ...
0
votes
1answer
1k 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? ...
0
votes
1answer
557 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 ...
1
vote
1answer
342 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) + ...
0
votes
0answers
184 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 ...
2
votes
0answers
252 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 ...
-1
votes
1answer
462 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 ...
0
votes
1answer
570 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 ...
0
votes
1answer
21 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 ...
1
vote
1answer
397 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 ...
1
vote
1answer
207 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, ...
0
votes
1answer
79 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 ...
0
votes
1answer
257 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
votes
1answer
291 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 ...
1
vote
0answers
92 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 ...
0
votes
0answers
61 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 ...
0
votes
0answers
161 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 ...
0
votes
0answers
55 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 ...
1
vote
1answer
101 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 ...
0
votes
2answers
1k 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: ...
0
votes
1answer
1k 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 ...
1
vote
0answers
1k 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 ...
2
votes
2answers
222 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 ...
1
vote
0answers
213 views

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 ...
3
votes
1answer
322 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 ...
2
votes
2answers
85 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 ...
1
vote
1answer
106 views

Does hardware RAID1 offer significant advantages to S/W RAID in a computer cluster that's highly redundant?

I'm about to set up a Linux cluster of 5 physical server nodes (more nodes to be added later, probably). the cluster will be managed by Proxmox (and yes, it works in software RAID) shared storage ...
1
vote
1answer
412 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 ...
0
votes
2answers
65 views

What is optimal sql server cluster storage solution?

I have been assigned a project where sql server is running on a single server with single raid 1 volume. This setup has worked fine until hardware failure resulted in about a day worth of downtime ...
0
votes
1answer
607 views

Apache Tomcat 7.0.57 Cluster & mod_proxy / mod_proxy_ajp

I have set up an Apache Tomcat Cluster with an Apache HTTP server and load balancing on CentOS 6.6 the following way: + 1 VM running HTTP server & 1 Tomcat instance (used for deployment, not ...
2
votes
0answers
238 views

Clustering with Jboss EAP and Load balancing with Haproxy

I'm doing load balancing with HAProxy and use JBoss EAP as application servers. The Haproxy server is configured to route incoming requests to the application servers. How can I integrate Jboss EAP ...
0
votes
0answers
155 views

Direct server return loadbalancer for mariadb galera cluster with 2 networks

Is it possible to configure LVS (keepalived) loadbalancer with direct server return (DSR) for 2 leg network setup? The desired architecture is as follows: mariadb galera cluster, where each node has ...
1
vote
0answers
124 views

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 ...
2
votes
1answer
689 views

CoreOS Cluster DNS setup

I'm unsure of how to setup DNS for a coreos cluster. Currently I have all of my api instances behind a haproxy load balancer and a DNS A record which points to the (elastic) ip of the load balancer. ...
1
vote
1answer
2k views

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 ...
0
votes
1answer
129 views

Adding hosts to existing 2012r2 Hyper-V cluster

Situation: Two separate clusters, server 2012 and server 2012r2 In process of disassembling the 2012 cluster and upgrading those hosts to 2012r2 Prior to this I must move all of the guests to the ...
1
vote
0answers
28 views

Does Stop-CauRun Stop the Current Server or the Whole CAU action?

When using a PreUpdateScript or PostUpdateScript with "Windows Cluster Aware Updating" and "Updating Run Profiles" would calling the cmdlet Stop-CauRun do any of the following: Would it actually ...
1
vote
1answer
1k views

“Applications and Services” is missing from Failover Cluster Manager

Microsoft instructions advise to use "Services and Applications" but it's missing from the Failover Cluster Manager. For example, the documentation for Test the Failover of a Clustered Service or ...
0
votes
0answers
1k views

Windows Failover Cluster - Create Cluster Wizard: error occurred while creating the cluster

I have 2 identical Windows Server 2008 R2 servers which I am trying to setup a failover cluster on. The "Validate a Configuration" passes, but the actual creation process produces an error: An error ...
1
vote
1answer
1k views

Intel MPI Gives 'channel initialization failed' error (mpirun)

I'm trying to setup a small cluster consisting of 3 servers. Their hardware is identical, and they are running CentOS 7. I'm using Intel's cluster compiler and MPI implementation. Everything is setup: ...
0
votes
1answer
449 views

Clustered Apache 2.4 LoadBalancer displays no content on /balancer-manager

I have a Clustered Loadbalancer (pacemaker, corosync, apache 2.4) on CentOS 7. There are two configuration files, one for the actual balanced site and one for the balancer-manager. When I access the ...
2
votes
1answer
335 views

Monitor network statistics with vnstat on CoreOS?

I notice that vnstat isn't installed on CoreOS. Is there a comparable way to monitor network usage on a CoreOS cluster? Certainly one could run vnstat through a Docker container but I assume that ...
2
votes
1answer
220 views

Using a JBOD for redundant NFS

I have a Xyratex sp-2224 JBOD enclosure (dual controller) and a pair of Dell servers with SAS HBAs installed that I'm looking to utilize in a redundant NFS cluster. The hardware isn't what I'm ...
8
votes
4answers
1k views

Test-Cluster Powershell cmdlet List vs Validate

The Powershell cmdlet Test-Cluster queries a myriad of data and performs validation tests which it wraps into a pretty report. If you run Test-Cluster -List you get a list of item's you can ...
0
votes
1answer
319 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 ...