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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3
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1answer
177 views

Choice of distributed filesystem for intensive reads and writes

I have a series of servers (HP ProLiant, 34 servers) each of which with 500 G of hard drive space. These servers are part of a computational cluster which runs processes that roughly fall into two ...
0
votes
1answer
187 views

SNMP walk on Virtual Ip not working? what can be the reason

I have two MSSQLcluster, at a time VIP [virtual ip] that will be assigned to on of the master. The problem is when i try to do any snmpwalk on VIP from a different machine its returning me a time out. ...
0
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2answers
52 views

How to broadcast a command on Windows

I am going to frequently deploy different versions of a program on a cluster of Windows machines (mostly Windows XP), so I am willing to use a command-line broadcasting tool (either built-in or ...
2
votes
1answer
126 views

Galera Cluster starting backup can't find innobackupex in the path

I am trying to get a Galera cluster running. I have the first node up and ready for connections. My second node, however, when trying to run wsrep_sst_xtrabackup gets the error "Can't find ...
0
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1answer
281 views

pbs check how much cpu a job is using / job % cpu usage

On a cluster a job is submitted to run on N CPUs. qstat -f doesn't show how much CPU resources the job is using other than the time. How does one check whether 100% of each CPU power is used? It is ...
0
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1answer
284 views

Is there any way to achieve a network fault-tolerant print server?

Our infrastructure is actually composed by a main datacenter in headquarters, where are centralized almost all of the services and aplications, and a smaller datacenter, in a building accross the ...
2
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2answers
1k views

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 ...
0
votes
0answers
566 views

No disks were found on which to perform cluster validation tests

I am trying to make a cluster of two Hyper-V machines running Windows Server 2012. There is a SAN available in which I have created several partitions to use such as J drive, K drive L drive etc. ...
0
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1answer
427 views

Apache with mod_jk with glassfish instances, large number of established connections for low number of users [duplicate]

I making a tuning for our production servers for a portal, we have 4 servers, 2 for web and 2 for app, and there is a firewall before and after web servers (so yes there is a firewall between app and ...
1
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0answers
72 views

PostgreSQL replication lag Ubuntu 11.10/12.04

I've a PostgreSQL cluster running on Amazon AWS EC2 instances with streaming replication and "hot standby" option enabled. I'm now gradually upgrading it from Ubuntu 11.10 to Ubuntu 12.04 LTS and I've ...
-1
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1answer
768 views

MariaDB Galera Clustering - Active Active - Operation not permitted error

I am having issues with MariaDB and Galera running on RHEL 6.4 & 6.2 64bit servers and getting them to cluster. I installed the required RPM's for Galera clustering: MariaDB-Galera-server ...
1
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0answers
65 views

Firewall rules between windows cluster

I have been given the task to define firewall rules between 2 Windows clusters. The first cluster hosts a clustered middleware application and the second cluster hosts SQL Server. The 2 clusters are ...
0
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1answer
179 views

HAProxy SSL connection error

Brand new to setting up SSL with HAProxy and Litespeed load balancer, just generated my certificate using the .csr and am trying to have HAProxy terminate SSL before sending it to the web worker ...
0
votes
1answer
34 views

Running jobs in a HPC cluster [closed]

I'm quite new to HPC environment. Is there any difference in running a job on a node utilizing 8 cores and running the same job on 8 nodes utilizing I core in terms of performance or walltime used. ...
-2
votes
1answer
121 views

Liferay cluster with SAN storage with ext3 [duplicate]

I'm deploying an liferay portal in a cluster which has 2 node load balanced, and config both to access to the same data location in a SAN storage devide. The problem is each node can not see the other ...
1
vote
1answer
53 views

How to create a slurm queue for the headnode

Is there a way to create a SLURM queue that runs on the headnode? I'd like to be able to do this as a first level testing queue sort of, before trying to run on multiple nodes. I've tried stuff ...
0
votes
2answers
211 views

MySQL geographic replication cloud

I currently have a standard local LAMP setup, (2 web servers, master/slave MySQL, load balancer). This is severing me well locally, but my global users experience slowness. I want to setup some ...
0
votes
2answers
200 views

Oracle Weblogic 10.3.5 Cluster creation issues

I'm trying to create a two node cluster with Oracle Weblogic 10.3.5. During the "Fusion Middleware Configuration Wizard" setup process, I'm not sure what to put in for the "Cluster Address" if I ...
2
votes
2answers
820 views

Why has Red Hat Cluster Suite stopped working?

I've been testing the Cluster Suite on CentOS 6.4, and had it working fine, but I noticed today [8th August, when this question was originally asked] that it's not liking the config that was ...
0
votes
1answer
334 views

MariaDB Galera Cluster hang after issue cluster command

When trying to cluster two MariaDB Galera servers on RHEL 6 together using the command: mysqld -uroot --wsrep_cluster_address=gcomm:// and the screen then sits there, and looks at me with this ...
2
votes
1answer
350 views

When trying to delete a table from NDB Cluster, I get the error “4243: Index not found”

In a Linux-based NDB-cluster consisting of 7 API nodes, 1 Management node and 4 NDB nodes, I am trying to drop a table. When I try to drop the table using MySQL Client, I receive the following ...
1
vote
1answer
345 views

Is there a programmatic way to determine free disk space on a Linux server?

I have a collection of Linux servers, each of which has a local hard drive with a /tmp directory. Occasionally, the /tmp directory on a server will fill up and cause errors. I want to automate the ...
1
vote
1answer
167 views

Is it possible to speed up network filesystem by sth like unionfs, aufs?

I need to speed up slow, large storage with local SSD drive. I figured out I could do this with union filesystems. Here are results with nginx reading data from: local SSD alone: ~140 ...
1
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0answers
401 views

How to configure cluster.conf for failover routing two networks?

I'm routing between an "external" subnet with Internet connectivity and two "internal" subnets, using iptables forwarding on a Linux box running CentOS 6.4: I'd like to now duplicate this router ...
3
votes
2answers
7k views

2012 Cluster service name failing

I have successfully created a cluster, but any services I try to cluster fail with the same or similar symptoms (I have tried clustering DTC and installing a SQL cluster). Environment: 2 – nodes – ...
0
votes
1answer
754 views

When creating a Win2012 cluster “The network name is already used on the network” no matter what name is used

I have a test setup that has 2 Windows Server 2012 VMs on Hyper-V joined to a windows 2008 R2 domain - there is an internal network whose DNS server is on the domain controller and an external network ...
7
votes
1answer
288 views

Heartbeat meatware STONITH on kernel panic

I have a two node cluster with heartbeat and DRBD managing a mysql resource. The failover works great if I halt the primary, reboot it, or disconnect the network connection. However, if the primary ...
0
votes
1answer
365 views

RedHat 6 Cluster Failover

I'm testing the RedHat Cluster Administration tool documented here: https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Cluster_Administration/index.html I have two ...
0
votes
1answer
73 views

Detect if the original node failed in tomcat cluster

I have two nodes in a cluster. Node1 initially servers requests. Loadbalancer redirects the request to node 2 if the first node fails. I would like to know if there is a way for the Node 2 to detect ...
0
votes
1answer
77 views

Intelligent, Location Dependent DNS

I'm new to complex network infrastructure but I'm quickly realizing that we're outgrowing our centralized load balanced cluster. The way we have things setup right now means that in order to add a ...
0
votes
1answer
501 views

Session replication in Tomcat

I have setup my cluster with one loadbalancer and 2 nodes with sticky session. I am using mod_jk for loadbalancing. I am having problem with proper session replication. I am using Tomcat 6. When I ...
0
votes
1answer
59 views

Authenticate ftp users on mysql through secure channel

I've to face this problem regarding security: some sFTP servers (proftpd) in a dmz that need to authenticate users against a mysql (native cluster|percona cluster|MariaDB cluster) through a secure ...
7
votes
2answers
148 views

What “pieces” are needed in order to set up a cluster of physical servers?

Background: Currently, we use Rackspace cloud servers. We have no intention to stop using them, but would like to look into setting up a cluster of physical servers (probably desktop computers in the ...
1
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1answer
2k views

WARNING: Context manager doesn't exist

I have cluster setup with session replication. I have one load balancer with 2 tomcat instances as the worker nodes. In one of the node I am getting the WARNING. NOt sure what it really means. Session ...
0
votes
1answer
217 views

Hyper-V - USB Disk mapped to VM

If I have a VM on a Hyper-V host with an IP 192.168.50.25 (VM IP), where the Host has an IP of 192.168.40.25. (The host itself has a virtual switch whose NIC patches into a procurve onto the VLAN ...
1
vote
1answer
42 views

Coherent logs from multiple identical nodes

I have multiple web heads running a stack containing Apache/mod_php/Magento/MySQL and more. Every time I need to view logs I find myself jumping on multiple servers to view logs in different files ...
1
vote
3answers
2k views

mod_jk produces Error smh errno=13

I am trying to use mod_jk for load balancing. Loadbalancer 172.17.8.189 (HTTPD+mod_jk) Node1 172.17.8.193 (apache tomcat instance 1) Node2 172.17.8.196 (apache tomcat instance 2) I checked my tomcat ...
0
votes
1answer
532 views

Failover Cluster Migration Wizard (SQL Install Portion)

Have 5 SQL 2005 to 2008 R2 clustered instances. I've setup a new cluster to prepare to use the cluster migration wizard. As I understand it you have to install SQL before running the cluster migration ...
0
votes
0answers
369 views

Server 2012 cluster - SAN volume - failover not working

The following configuration is available: - 3 HP SAN disk Enclusores / 2 SAN controller; HSV200 (FC) - 2 HP Brocade SAN switches - 2 HP blade servers, each with a QLogic FC HBA QMH2462 - SAN volume is ...
8
votes
2answers
212 views

A roundrobin for incoming files

A bunch of new files with unique filenames regularly "appears"1 on one server. (Like hundreds GBs of new data daily, solution should be scalable to terabytes. Each file is several megabytes large, up ...
1
vote
2answers
40 views

2008 Clustered Services (SQL) to 2008 R2 Clustered Services

I've found plenty of articles for upgrading SQL in a clustered environment from SQL 2008 to SQL 2008 R2. However, I have not found much information in relation to migrating a current Server 2008 ...
0
votes
1answer
78 views

LDAP URL example: is it possible / correct to use only the domain without the hostname?

We have an application which connects to an Active Directory (MS) using LDAP protocol. We give usually the following parameters: ldapUrl = ldap://myserver.mydomain.ext:389 ldapBaseDn = ...
3
votes
2answers
63 views

Is it possible to have automatic failover of a windows service without windows clustering?

Due to a partial failure of our SAN we have switched our message queuing (Active MQ) from using network storage to using local storage. Because the secondary server is no longer sharing the same ...
1
vote
0answers
226 views

mod_jk tomcat error handling

I have a strange problem with my tomcat cluster. The cluster consists of 1 Apache with mod_jk and 6 Tomcat servers - each tomcat server is a own virtual machine. The cluster works as expected, ...
2
votes
1answer
257 views

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 ...
1
vote
2answers
43 views

Certificates for clusters

I have read the various threads regarding clusters (behind the load balancer) and certificates. I am trying to implement this in our company. Firstly Our compnay policy is not to allow exporting of ...
0
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0answers
378 views

Setting up computational cluster using infiniband fails

My task: I need to assemble computational cluster, consists of two nodes using infiniband technology. When I try to start mpirun ... for two nodes, the process hangs. If i try to use flag ...
-3
votes
1answer
101 views

Mysql Cluster Sharding/partitioning [closed]

Ok so i have mysql cluster setup but what i need is say table assets to be split among the nodes, not replicated. as the purpose of me setting up the cluster was due to lack of hard drive space so how ...
0
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0answers
706 views

Confusion setting up a simple tomcat6 clustering on ubuntu 12.04 using mod_jk: status page won't show

am a little confused when setting up 2 tomcat6 instances cluster in a clean ubuntu server 12.04. i didn't install default tomcat6 i used tomcat6-user's tomcat6-instance-create to create 2 instances. ...
0
votes
1answer
171 views

Memcached distribution

I have a question about memcached distribution across nodes. We have 20 memcached nodes with 200GB memcached on each. Our apps are PHP apps. $memcache->setOption(Memcached::OPT_DISTRIBUTION, ...