High availability is an architectural consideration often involving degrees of redundancy to insure availability in case of system or component failure.

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363 views

How to make active/passive jboss resource in pacemaker

I want to configure my pacemaker for jboss server. I have 2 nodes with mysql master/slave configured. The problem is I want to start jboss on node which is located master database. The one possible ...
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1answer
1k views

Configuring HAProxy with memcache with failover

I'm configuring a new set of servers for an existing Wordpress site, and it's been requested that memcache be available and made more resilient. The idea proposed is to have HAProxy send requests to ...
3
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1answer
340 views

corosync binding to 127.0.0.1 instead of correct interface

I have the following problem when trying to implement a two-node failover cluster, using Hetzner as the hosting provider. my corosync.conf is as follows: # Please read the corosync.conf.5 manual ...
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1answer
994 views

job interview - technical questions (hardware / network) [closed]

i recently had a phone interview, and did not get the job. i'm curious if i didn't get the technical questions correct, or whether there was something else about my interview that caused me to not get ...
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1answer
256 views

corosync and multiple load balancers

I am trying to provide HA capabilities for our load balancers (nginx, pgpool and haproxy optionally) using pacemaker/corosync. I have defined three primitives: 1 for the failover IP, 1 for ...
4
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1answer
987 views

Should VMware HA Admission Control be enabled for small (2/3-host) clusters?

Take the following common scenario... A basic vSphere cluster running two or three hosts, shared storage and a token set of virtual machines under Essentials Plus or greater licensing. Should HA ...
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1answer
43 views

domain redirecting/forwarding during server shutdown temporary [closed]

I rack my brain how could I solve the following issue: my website/server needs to be available all the time, so just few minutes downtime could be critical I would run a separate server (server ...
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2answers
63 views

How to create a redundent webserver using virtual machines

I would like to create a fail-over web server using one physical box and 2 virtual instances. What I am aiming for is the host OS monitors performance of a web server running in a virtual machine (ie ...
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1answer
196 views

Is possible to use Pacemaker failover without hardware?

Is possible to use Pacemaker failover without hardware? On quickstart http://clusterlabs.org/quickstart-redhat.html you can find the followowing commands: ccs -f /etc/cluster/cluster.conf ...
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0answers
38 views

Prevent NGINX from rerouting to a backend that was previously down

I'm using NGINX's ip_hash directive to ensure that client requests always end up at the same backend server. In the case of a backend server outage, NGINX will reroute to the available server, and ...
1
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2answers
618 views

Best way to load balancing between AWS and Rackspace?

I have a SaaS product hosted on AWS and I would like to have the same infrastructure hosted on Rackspace (or any other host) to offer a high availability (eventually load balancing) for my users in ...
0
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1answer
74 views

Windows Server 2012 Virtualization for Limited Downtime? [closed]

We're planning on purchasing a new server and consolidating most of our websites onto it. The initial thought was to use Windows Server 2012 with 4 VMs on it (1 e-commerce web, 1 e-commerce database, ...
1
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1answer
365 views

Log into a specific server in a Windows 2012 Remote Desktop Collection

I have 4 Windows 2012 Remote Desktop servers in 1 collection. All 4 of the servers have the RD Session Host role. I've also put the collection into High Availability Mode, so all 4 servers also have ...
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2answers
67 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 ...
2
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1answer
1k views

ESXi Beacon Probing Limitation - Three Switches Required?

We are currently using Link Status Only for our NIC Teams on our VM hosts, but recently ran into an issue where one of our two switches had a memory error and stopped passing traffic. All of our VM ...
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1answer
185 views

Azure extra small vm availability set [closed]

My current extra small vm reaches the limits, so I decided to create a second extra small instance and add the two into a availability set so my service is everytime available and through the load ...
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0answers
53 views

DRBD mount randomly unmounts itself

We have setup setup an NFS HA "cluster" using drbd/heartbeat. Everything works as expected when tested... If the instance nfs1 goes down, nfs2 picks up and everything seems to be fine. On both ...
1
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1answer
206 views

Bond0 Failover when link light stays up: High Availability Network

Configuration: Two switches, each with a separate internet route Centos servers with eth0 and eth1 bonded as an active-backup on bond0, eth0 in on switch and eth1 in the other /etc/modprobe.conf ...
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0answers
176 views

configure heartbeat HA on Amazon VPC instance

I'm trying to implement HA with Heartbeat (and monit) on two Amazon VPC instances. I read many articles about it and I tried all possible options I can think of. few articles I read (don't work for ...
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1answer
194 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, ...
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0answers
1k views

LVM DRBD Shared between nodes proxmox

Context : I have proxmox cluster with the volume group shared with drbd for the VM - KVM. I have a problem with drbd. Indeed, when a node disconnect, the associate link between the differents nodes ...
1
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2answers
1k views

Per-packet round-robin load balancing for UDP

I need to load-balance UDP traffic between a number of "realservers" and do it in a truly round-robin fashion. I've started with keepalived, but unexpectedly discovered, that LVS treats UDP traffic as ...
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0answers
294 views

Strange Keepalived VRRP email notification

I have a 3 nodes keepalived (K1 to K3) installed and receiving email notification. The setup of keepalived is K1 VI_50, priority 100 VI_51, priority 98 VI_52, priority 99 K2 VI_50, priority 99 ...
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1answer
114 views

IP-based load balancing on external and internal interface

I have a certain distributed (as in, multiple components on multiple machines) service, that should be made available from the outside world. So, in LVS terminology, the clients are "on the internet", ...
1
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1answer
96 views

What design considerations should go into a proper Bitcoin exchange (or any other automated online trading system)? [closed]

Following the epic fiascos of the two main Bitcoin exchange sites (Mt.Gox, which went offline due to sheer traffic load during the worst market crash in the history of Bitcoins, leaving people with ...
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0answers
102 views

Solr on a two node Jboss cluster

Are there any issues with deploying Solr on two node jboss cluster with the index shared on a NFS mount point? We would like to do this for high-availability across data centers.
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1answer
224 views

SSL Session Persistence - HA Heartbeat

I have two servers, let's call them Milo and Otis. Now Milo and Otis are setup to be an active-passive pair of highly available servers where Milo is usually the master and Otis stands-by waiting for ...
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1answer
671 views

Howto setup 3-node heartbeat cluster?

I want to set up a virtual IP on three nodes using heartbeat. Currently, I have this: ha.cf: # Facility to use for syslog()/logger (alternative to log/debugfile) logfacility local0 # ...
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1answer
88 views

How to connect to mysql-master-ha from my application server

I am trying to use mysql-master-ha. I managed to get it connected with the master and slave mysql servers. Now I would like to know how to connect to mysql-master-ha from my web application server ...
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3answers
3k views

corosync + pacemaker + nginx

I have been trying to configure and implement corosync + pacemaker + nginx to my vbox to create a High-Availability set-up between web servers. But can't find an exact tutorial on how to make it work ...
0
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1answer
601 views

Tomcat Failover High Availability (active / passive)

we have a jee web application running on apache tomcat , we need to deploy this application on production environment and we decided to use failover structure so we have one server active and another ...
3
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3answers
436 views

How can I create a “fail whale” for my website?

I have a website that we load-balance across a few machines. The load-balancer (a Brocade ServerIron ADX) is on the local network. I know it has the capability to configure a "backup" ip address to ...
0
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1answer
129 views

Red-Hat Cluster doesnt migrate services on node shutdown

I have a RHCS with two nodes and manual fencing. when I restart Node 1 (the primary) it migrates both services to Node 2 automatically. but when I shutdown Node 1, it doesnt happen and I need to use ...
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272 views

MySQL High Availability with VMWare/DRBD/Heartbeat still common practice?

Is it still common practice to use a DRBD/Heartbeat solution for a high available MySQL Instance when the whole environment is virtualized (in our Case VMWare) Are there other/better solutions out ...
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1answer
833 views

Load balancing with High Availability - SQL Server + IIS using AWS

This is my first time load-balancing with high-availability using Windows and SQL Server. Looking for some validation and input on my planned setup. Now, typically when I want to create a HA ...
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0answers
73 views

Solaris and Hot-Standby

i have a short question. is it possible to create a hot-standby-cluster with 2 nodes and solaris 10? in Linux i would use DRBD and Hearbeat/corosync, but in Solaris? maybe do you have an tutorial? ...
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1answer
50 views

Backing up a mirrored SQL environment

I have 2 SQL servers in Mirror configuration. I want to backup these servers but backing up the SQL databases in Mirror state causes an error. These two mirrors also have a witness set. I would ...
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0answers
745 views

Exchange 2010 DAG Failover Cluster DNS Issues

I am having an issues with my Exchange 2010 servers. I have two servers that have HUB/CAS/MAILBOX installed on them. They are configured to use DAG failover cluster. I expereienced an issue recently ...
0
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1answer
515 views

Setup HA postgres database, failover concept

I want to setup a HA postgres database. I setup master and slave database with synchronous streaming replication on different physical servers. When there is an error in the replication, the slave db ...
3
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1answer
288 views

Virtual IP Failover when machine is overloaded

We have been using keepalived in combination with a virtual IP address for two years now. In the rare case that a machine crashes this works very well. But when there are issues on the box itself we ...
3
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1answer
1k views

Does HP IRF work the way I think it does?

I finally have approval to better centralize our Ethernet. When last I left off I was looking to the future to figure out how best to handle expansion. Now, I have answers. I now have a pair of A5820 ...
0
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1answer
2k views

Keepalived's virtual_router_id - should it be unique per node?

I have two nodes running keepalived, and two VIP, e.g. Node 1 Node 2 VIP1 VIP2 So in each node, I have two definition of vrrp_instance, so I assume the two vrrp_instance in my ...
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0answers
218 views

Unable to remote desktop using failover cluster name

I am using Microsoft Failover Cluster and I have 2 nodes - say node1 & node2. The nodes are successfully accessed by remote desktop. but the cluster name is not accessible. The cluster name is ...
5
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1answer
778 views

VMware vSphere DRS affinity rules for more than 2 guests

I've received a request to add disaffinity/anti-affinity rules on a set of virtual machines in a VMware HA/DRS cluster running VMware vSphere 4.1. The client has four hosts and wants to keep certain ...
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1answer
329 views

Advantage of Microsoft Cluster over Microsoft Network Load Balancer

Till recently, I assumed that Microsoft NLB worked at an OS/Machine level rather than an Application Level. i.e. the NLB just monitors heartbeats on the machine to check if machine is alive and then ...
3
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6answers
309 views

Should HA hardware be in separate cabinets?

I want to host (co-located) a service at a Pier1, Q9 or some similar hosting facility. Is it best practice to put my failover hardware in separate cabinets, and in your experience, will the hosting ...
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1answer
73 views

Highavailability/Global Loadbalancing of clusters [closed]

I know this website 1channel.ch which has like 4 servers in 4 different datacenters across the globe (czech republic, estonia, sweden, germany). What happens is as i am browsing this website the ...
0
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1answer
171 views

Using Amazon route53 for high availability

Using Amazon Route53 DNS, is it possible to build a highly available setup pointing to multiple web servers not on Amazon? I don't need to worry about session stickyness. Let's assume I have two web ...
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1answer
195 views

HA Options for Windows Servers

We are looking at different options to allow us to stay up and running when our primary datacenter (DC1) goes down for any reason. What is the main difference in having a offsite server updated all ...
0
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1answer
258 views

How to setup a failover solution for Windows 2003 SMTP Server?

I'm currently running Windows SMTP Server on a rented Windows 2003 Server VM. There are times when my hosting company network is down and my clients can't send their emails via the SMTP Server host I ...