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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12 views

How to retain the Session vars when deploying in Clouds and Cluster servers?

How do you ensure your user retains the same session information when your application is deployed to a cluster?
0
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1answer
352 views

Windows 2012 R2 Cluster

This is my first time building a Failover Cluster. I run the validation and every time I get the following. "Failed to prepare storage for testing on node {SERVER NAME}: The remote procedure call ...
1
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0answers
63 views

Could HAProxy disable the Apache Instance on the same node it is running?

I have a setup with three VMs that are running on a core i74xx. The machines form a LAMP cluster with HAProxy doing the loadbalancing. After running multiple load tests I found out, that throughput ...
1
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1answer
32 views

How to sync clock and UIDs across different nodes of a cluster with Ubuntu?

I am new to cluster computing and Ubuntu. We have a computing cluster with 4 nodes (10 cores per node) with Ubuntu installed. The cluster is meant for scientific computing. To install a load ...
0
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1answer
26 views

Pool of machines without authentication?

I am working on a cluster of linux machines. What I need is for authentication to not be needed between the machines in this cluster, but required from outside. I have considered the idea of setting ...
0
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0answers
148 views

RedHat Cluster 6 node won't see shared volume group

I try to create a shared clvm volume group shared between 2 nodes of a Red Hat Cluster 6. Here is the procedure I followed: [root@node1 ~]# pvcreate /dev/mapper/mpathab [root@node1 ~]# vgcreate -c y ...
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0answers
109 views

Simultaneous server crash in fail over cluster

I have 2 servers in a failover cluster. The cluster defines a shared 'ClusterStorage' drive. The drive maps to a SAN device through iScsi. Recently, the 2 servers rebooted on their own at the same ...
0
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0answers
411 views

how to do automatic failover of mysql / galera cluster

I have two mysql/galera clusters of three nodes each (two + garb node). The clusters are in separate DC's (dc1 and dc2) The cross cluster replication happens between node1-dc1 and node1-dc2 I want ...
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0answers
137 views

Ceph remain in HEALTH_WARN after osd remove

I have a cluster of 3 servers with cepth storage over 9 disks (3 each server). One osd is going down/out and so I "remove" it, after that system start to rebalance data over the remainig osd but after ...
0
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3answers
764 views

Can we build a Hyper V failover cluster without a SAN or other shared storage?

I have a question about Hyper-V Failover Cluster. I have 2 server Hyper-V and want to use a failover cluster. As far as I know, I need a SAN server for that, so do we need it in here?
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1answer
38 views

Keepalived in the AWS autoscalling group

I want to deploy Keepalived in the AWS autoscalling group. The issue that Keepalived need to know ip address of the each node in the cluster, that is difficult in the elastic environment, where we can'...
0
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2answers
514 views

pcs status error httpd_monitor_5000 on server 'not running' (7):

Error Message Failed actions: httpd_monitor_5000 on abc-zabserver-b 'not running' (7): call=65, status=complete, last-rc-change='Wed Jul 15 21:44:43 2015', queued=0ms, exec=8ms pcs status [...
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0answers
99 views

Windows Cluster An error was encountered while determining shared storage

Our SAN manager has added a new disk for our cluster. this is a new 6TB disk that will be used for backup and will be part of a file share. I have put the disk online, initialized it and assigned the ...
0
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1answer
47 views

Galera cluster implementation questions

I've just successfully created my first Galera cluster using MariaDB 10.0.20 between three servers. I have a few questions regarding my implementation: 1. what will happen if one server becomes ...
0
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1answer
44 views

SQL clustering without WSFC (Windows Server Failover Clustering)

Is it possible to cluster, or make SQL "highly available" without having to pay the huge enterprise prices? By the looks of it, any type of SQL clustering requires enterprise edition Windows Server. ...
4
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1answer
166 views

Can you list a Datastore Cluster's sDRS Schedule via PowerCLI?

We have a lot of datastore clusters, most if not all are supposed to have sDRS schedules applied to stop them moving VMs at busy periods. Obviously we could trawl through them manually to check if ...
1
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1answer
692 views

Multiple vCenter Services for redundancy

I've been reading up on linked mode, but this only applies to the management on multiple clusters from a single vCenter via linking other vCenter's into it. My question is - can you have two servers (...
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3answers
144 views

How does HA / failover work?

Let's say we have ten servers, each one has a copy of stateless application. user enters address in a browser / client program. dns server returns a list of ip (however many people say that dns ...
0
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1answer
62 views

Pacemaker and Stonith : passive node won't bring up resources

I'm working with Pacemaker and Stonith for High-Availability with a 2-node cluster (nodes called here A and B). Both nodes have one IPMI as fence device. The deal is : A is currently running ...
0
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1answer
26 views

How to manage access to nodes in a cluster?

I am about to set up a server cluster for our company's web applications. At the beginning there will be 3 hardware servers in Proxmox HA setup in a remote datacenter running about 20-30 VMs all ...
1
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1answer
418 views

MariaDB Galera Cluster, Force Sync

I have three servers in a multi-master Galera cluster. I've imported some old databases recently, and noticed that the tables were being created across all three, but the data wasn't being replicated....
3
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0answers
648 views

Pacemaker ocf:heartbeat:IPaddr on different subnets

I'm trying to add a Pacemaker virtual IP address; with it, the gateway, and the two VMs it serves on different subnets. I've only done this before with all IPs on the same subnet, and I need some help....
0
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1answer
170 views

Cassandra NetworkTopologyStrategy

I would like to configure the following multi-datacenter Cassandra cluster: DC-EUROPE has 3 Cassandra nodes (1.1.1.1, 1.1.1.2, 1.1.1.3) DC-ASIA has 3 Cassandra nodes (2.2.2.1, 2.2.2.2, 2.2.2.3) Each ...
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1answer
37 views

What happens if fleet can not meet the requirements for an unit

Take a look at the following scenario: I have a CoreOS / fleet cluster with 4 nodes. There are 4 apache units with the following line Conflicts=apache@%i.service One machine goes down. Fleet ...
3
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1answer
41 views

NetApp cluster fail to start

I have a big problem with my FAS2020 (configured as iScsi storage for 2 esxi 4 server). I couldn't ping the 2 ip address of the FAS so I connect by the serial port with putty for monitoring the boot ...
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1answer
136 views

What distributed FS, with small files read / write workload perform better?

I have 2 machines sharing storage via iscsi (multipath), soon we add another one, this machines are Web app servers that read small files on shared storage ( < 256kB), and write them back. so we ...
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0answers
187 views

Why both nodes in OCFS2 cluster keep rebooting?

We created an OCSFS2 cluster by using SUSE Linux High Availability Extensions on SLES SP3. The cluster nodes are two Apache servers which share one disk. We have stonith enabled and SBD daemon. It ...
0
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1answer
423 views

MariaDB Galera Deployment

I am looking to experiment with MariaDB 10 Galera Cluster. I am looking for highly available, scalable and reliable architecture. Basically I am curious what would be the better architecture and would ...
0
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1answer
94 views

Pacemaker continously logging “Changed active directory”

I have a newly installed CentOS 6.6 two-node cluster using Pacemaker. Every 10 seconds /var/log/pacemaker.log shows this "Changed active directory to /var/lib/pacemaker/cores/root" message (and ...
2
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1answer
182 views

HA Cluster with OpenVZ and DRBD

I would like to create an HA Cluster using OpenVZ and DRBD. I found this tutorial http://www.olindata.com/blog/2013/12/building-ha-cluster-openvz-drbd-heartbeat-and-pacemaker and I got as far as Step ...
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0answers
138 views

Run Server from Clustered File Server DRBD & GFS2

We are trying to eliminate a single point of failure for our files without a SAN. We currently have a single server for file serving (locally), web server, and database (in VM). Looking at using DRBD ...
2
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2answers
458 views

Mount two nfs's shares from different storage over the same directory on linux

I have a set of 4 Linux web servers on cluster all of them have the same mount point: /folder This /folder is a NFS mount share over a NAS but is full and no more luns/disk are available to expand ...
3
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1answer
218 views

zpool disappears whenever solaris cluster reboot or power cycle

I have following setup Oracle Solaris 10 -> 5.10 Generic_147147-26 sun4v sparc Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit production Oracle Solaris Cluster 3.3u2 for Solaris ...
2
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2answers
3k views

Redis high availability and load balancing

I'm using Redis for some time and now we want to move to a redundant cluster which would be fault tolerant, highly available and load balanced. I principally use Redis for some PHP web application ...
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0answers
254 views

File locking with CTDB and GlusterFS not working

We are having issues getting our GlusterFS and CTDB implementation to work. It could be that what we are attempting to do is not supported but I'm not able to understand why. We have two file servers ...
0
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2answers
870 views

Utilizing A Secondary IP On A NIC In A Windows Cluster

RELEVANT INFORMATION I have a windows cluster with 3 nodes in it... Node1 Node2 Node3 I have 4 NICs on each node... NIC1_Host NIC2_Virtuals NIC3_Cluster_HB NIC4_Live_Migration This is the ...
10
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1answer
797 views

Why does requesting GPUs as a generic resource on a cluster running SLURM with the built-in plugin fail?

Disclaimer: This post is quite long as I tried to provide all relevant configuration information. Status and Problem: I adminster a gpu cluster and I want to use slurm for job management. ...
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0answers
148 views

What fence device setup would prevent a mutual-STONITH in a two-node RHEL cluster?

I've got a Red Hat cluster (corosync+rgmanager) software on RHEL 6.6 on physical Dell servers with iDRAC. This cluster is for stateless application (stunnel, a TLS gateway), so it doesn't need and ...
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1answer
48 views

How I do to run only a software in more than one computer? [closed]

I need to run a unique instance of a software in more than one computer, how I do this without a centralizer server? For example: 4 computers interconnected by the local network, 2 of then has "the ...
4
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1answer
59 views

SAS balancing vs Network balancing

I want to configure file server in MS Windows Server 2012 R2 environment, which would load balance traffic. I have got a SAS disk array with 2 SAS controllers which is connected to 2 Hyper-V cluster ...
0
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2answers
153 views

How to enable “persistent mode” in Windows failover cluster manager 2012?

In Windows Server 2008 R2 there was a checkbox named "Enable persistent mode" on a General tab in the Properties of a cluster resource. In Windows Server 2012 that seems to have disappeared. My ...
4
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4answers
6k views

Two-Node Server 2012 R2 Hyper-V Cluster: Is it possible use local physical disks in the cluster?

Looking at the following Clustered Shared Spaces TechNet article, and it looks like this only applies to hosts sharing a JBOD enclosure by way of external SAS backplane. However, each host in the two-...
2
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1answer
273 views

Why Failover instead of Load Balancing for HA

From my understanding with failover clustering, only one machine is actually working, which means the other one(s) are sitting idle. So why would one use failover clustering instead of using a load ...
0
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1answer
186 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 availability....
0
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1answer
82 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
319 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
110 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 ...
13
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2answers
5k 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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0answers
600 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
2k 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? ...