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

learn more… | top users | synonyms (1)

0
votes
1answer
35 views

S3 dropouts in one region only - is this normal?

I'm using S3 to serve static image assets to a website. I'm a developer in Montréal, Quebec. My client's office is in LA. Once every month or three we're seeing S3 completely fail to serve images to ...
0
votes
1answer
240 views

vSphere High Availability, Fault Tolerance and Snapshots

I've heard claims from a vSphere server administrator that VMs configured for high availability continue to transparently function even in the event of an ESXi host failure. He also claims VMs ...
0
votes
2answers
573 views

the pacemaker can't start the drbd resource

here is crm the configure show [root@node1 /]# crm configure show node node1 node node1.mycluster.org node node2 node node2.mycluster.org primitive Apache apache \ params configfile="/etc/...
0
votes
1answer
2k views

pacemaker config resource for nginx

i'm trying to build cluster by two vm using virtualbox i follow this tutorial http://www.tokiwinter.com/clustering-with-drbd-corosync-and-pacemaker/ and type the command as below [root@node1 data]# ...
0
votes
0answers
139 views

Add security/authentication to mongodb (2.6) without downtime?

We have a 3 node replica set (running 2.6.1) that's running mostly defaults. We'd like to add authentication, but do it without downtime. I'm fine with restarting the nodes one-by-one and even ...
1
vote
1answer
275 views

Corosync 2.3.3: Unable to enable cipher

I'm trying to set up a new pacemaker/corosync stack of 2 machines. I was using it before with corosync1, but on Ubuntu 14.04 I've got corosync 2.3.3 OK - I said, and tried to use this version of ...
-1
votes
2answers
144 views

Never miss a HTTP post [closed]

I have a webservice that have a couple of "machine" clients connected to it that does HTTP post with data once in a while. The nature of the service is that I cant allow the service to loose a single ...
1
vote
0answers
98 views

Running iSCSI LIO with high availability

I've build a two node storage setup with OCFS on top of DRBD to provide storage for a couple of ESXi servers. Will it be possible to setup iSCSI targets on both storage nodes and make one of the nodes ...
0
votes
2answers
935 views

Centos 6.5 configuring HA cluster

I need to configure HA cluster using 2 computers. But I've got a problem, when I'm trying to start a heartbeat service it starts but throws an error. Here's the error message: Starting High-...
1
vote
1answer
188 views

High Availability/Failover hardware hookup

I'm learning about clustering and high availability techniques, and stumbled upon an article about configuring a network with a pair of servers, using DRBD for replication and heartbeat for monitoring ...
0
votes
2answers
1k views

corosync fails to install

I was trying to setup cluster using corosync and pacemaker on RHEL6 (CentOS release 6.5) I have added following repo data [haclustering] name=HA Clustering type=rpm-md baseurl=http://download....
2
votes
1answer
134 views

Why to use fencing when you already have redundant communication links?

This article stays that you should use both fencing (aka STONITH) and redundant communication links. I'm trying to understand what benefits STONITH gives in case of split-brain. Consider for example ...
5
votes
2answers
1k views

Which STONITH hardware for power fencing?

I'd like to setup a two node high availability cluster using corosync/pacemaker/drbd. For that, of course, I need fencing. As far as I understand, all IPMI/iLO/... solutions do the job, but only as ...
3
votes
2answers
3k views

Static IP in AWS but with possible Load Balance feature

I am playing a bit with AWS. My goal is to setup infrastructure, which will have static IP on outgoing connections (requirement from payment provider which solution has been implemented in our app) ...
1
vote
1answer
1k views

Simple fencing/STONITH script in Centos 7

I am installing a simple Corosync/pacemaker/drbd high availability cluster using Centos 7 and would like to provide fencing/STONITH using custom hardware (power switches using USB connections). As ...
0
votes
0answers
56 views

HA router with keepalived showing unexpected traceroute

I have a couple of routers in HA using keepalived vrrp daemon under linux. Here are the addresses x.x.x.129 floating (keepalive) x.x.x.130 router1 (static) x.x.x.131 router2 (static) Something ...
0
votes
3answers
100 views

Load balancing for a running server process with sessions

I'm developing a server application that accepts incoming connections and works with client applications. The customer wants to have two machines working: in case one goes offline, the second will ...
-5
votes
3answers
91 views

Web-based System High Availability [closed]

I'm a SysAdmin in one of the construction sites in a remote place. There is no reasonable internet speed can be reached there except a poor 3G/4G signal coverage which provide the users with non-...
1
vote
1answer
2k views

redhat cluster failover not working (corosync [TOTEM ] Retransmit List)

I'm using following: [root@kpdbm01 ~]# cat /etc/redhat-release Red Hat Enterprise Linux Server release 6.5 (Santiago) [root@kpdbm01 ~]# uname -a Linux kpdbm01 2.6.32-431.20.3.el6.x86_64 #1 SMP Fri ...
0
votes
1answer
171 views

Avoiding a Single Point of Failure with link aggregation

I have a requirement for a system with no Single Point of Failure. The client have offered two Ethernet cables per server. Each of the servers will connect into their network, however I want to set-...
0
votes
2answers
571 views

Corosync :: Restarting some resources after Lan connectivity issue

I am currently looking into corosync to build a two-node cluster. So, I've got it working fine, and it does what I want to do, which is: Lost connectivity between the two nodes gives the first node ...
10
votes
2answers
633 views

RabbitMQ - How I do configure servers for zero-downtime upgrades?

Having read through the docs and RabbitMQ in Action, creating a RabbitMQ cluster seems straightforward enough, but upgrading or patching an existing RabbitMQ cluster seems to require the whole cluster ...
0
votes
1answer
1k views

iptable CLUSTERIP doesn't work

We have some requirements which explained here. We tried to satisfy them without any success as described. Here is the brief information: Here are requirements: High Availability Load Balancing ...
1
vote
1answer
1k views

Multimaster Keepalived Configuration (Virtual IP with Load Balancing)

Here are requirements: 1. High Availability 2. Load Balancing First configuration 1. Two linux servers have been configured with one static IP for each: 10.17.243.11, 10.17.243.12 2. Keepalived has ...
0
votes
1answer
489 views

HA - Heartbeat / Pacemaker - CentOS - Manual Symlinks

I have a MySQL Master <> Master pair setup for HA. I would like to setup automatic failover not just if the node hosting the current write mysql instance goes down, but also if the mysql instance ...
0
votes
2answers
636 views

Keepalived loses VIP upon power cycle of master

I have two servers running Keepalived 1.2.7 with hostnames left and right. Here are the configs: # keepalived.conf on left vrrp_instance VI_1 { state MASTER interface eth1 ...
0
votes
1answer
402 views

uwsgi + Django with nginx: High Availability Setup

Moved from : http://stackoverflow.com/questions/25304968/uwsgi-django-with-nginx-high-availability-setup to here. I was setting up High Availability on RHEL 6.5 . My Stack is 1. uwsgi 2. nginx ...
0
votes
2answers
3k views

Microsoft SQL Server Standard High Availability without Shared Storage

I'm a software dev with little experience managing SQL so please bear with me! We are developing a piece of software that needs to be highly available, with a significant degree of resilience. This ...
3
votes
1answer
2k views

How to lower Gluster FS down peer timeout / reduce down peer impact?

The setting: Two fresh CentOS 6.5 server with latest updates. Both have a fresh install of Gluster 3.5.2. What I did ( from the perspective of server 2, shared1 and shared2 are logical volumes ) : ...
2
votes
1answer
178 views

What are the options for a HA system?

I'm looking into creating a HA Linux machine for my client's website. What are the main options I have, or a place/article where I can find out more? I would LOVE if it was a single-image, too, so ...
-1
votes
1answer
167 views

What FLOSS linux software should I use for high-availability on an FTP server on vmware? [closed]

I don't mean this as an opinion-based question. I want to know if my assumption is correct to use a network-oriented tool (keepalived) as opposed to a cluster-oriented tool (heartbeat) in a scenario ...
5
votes
1answer
2k views

VMware FT, App HA: What happens if vCenter Server is offline?

I am interested in the two features named "Fault Tolerance" and "App High Availability" which are part of some VMware products. As far as I understand the vCenter Server instance is needed to perform ...
2
votes
1answer
52 views

Website failover across internet connections

Requirement For a network having 4 static IP internet leased line connections linked to hosting a website. What are the current strategies one can apply to ensure high availability in case of ...
-1
votes
1answer
125 views

Setup Galera Cluster with two servers

Can I Create Gallera Cluster with two servers ?? Actually I have 6 servers: 2 Server for Load Balancer 2 Server for Apache Or anyone here can suggest me how to create High Availability Web Server ...
1
vote
0answers
318 views

Haproxy load balancing TPS lower than single node

I have 2 apache2 servers running in the back end and have a haproxy between them and the clients. If I bench tested anyone of these apache2 severs with ab i get north of a 1500TPS however when I bench ...
1
vote
1answer
760 views

Corosync dynamically add node

I have been experimenting with Pacemaker & Corosync for a HA setup. I installed it on two Ubuntu 14.04 Linode's and after a lot of back and forth on outdated config examples and tutorials, managed ...
1
vote
1answer
340 views

LVS + HA Proxy for L4 to L7 load balancing

Currently we are using HA proxy for our load balancing needs. We are planning to integrate LVS with HA proxy to create a load balancing solution that can take care of L4 to L7 load balancing and HA. ...
4
votes
3answers
231 views

Website high availability without load-balancer?

I'm considering options for changing a 'high availability' website that provides a service via an https api. The current setup is: Two self-contained VMs, from different cloud providers (AWS and ...
1
vote
2answers
727 views

IBM V7000 firmware upgrade effect on mounted LUN

We've IBM storwize V7000 Storage where the firmware is going to be upgraded to latest version.. This will require a reboot to the storage. I've got arround 10 LUN's (almost 10TB) coming from this ...
-2
votes
1answer
195 views

What's the best way to sync folders across 03 or more webservers? [closed]

I have 03 servers and I want to sync some folders across them. I'm using DRBD + OCFS2 for a year or so, but it doesn't support more than 02 servers right now. I read about GlusterFS and CEPH, but ...
1
vote
0answers
209 views

Redundant Debian Gateway

I have to configure a redundant gateway with Debian boxes and I would like to get some recommendation what's the best solution in my case. There are certain limitations in my setup and I have to go ...
0
votes
3answers
5k views

XenServer HA (failover VM's) without shared storage

In the university from Uruguay where I work, we have 2 IBM BladeCenter S with 4 server blades each one. Each blade have XenServer 6.2 installed and working. Our idea is have each BladeCenter in ...
5
votes
0answers
445 views

Using ZFS head node as database server?

I'm using a dual-head ZFS-backed NAS for high availability cluster shared storage, based on Nexenta's recommended architecture as seen here: The disks in 1 JBOD will store the database files for a ...
2
votes
1answer
106 views

Should each machine in a high availability cluster have same time zone?

I'm curious if people with experience think it makes sense to give all machines in a replication cluster the same time zone and time regardless of physical location to help ensure that dates are ...
0
votes
1answer
2k views

HDFS' ZKFC service unable to start

CDH4's ZooKeeper Failover Controller (ZKFC) has been installed. Starting the ZKFC service: [vagrant@localhost ~]$ sudo service hadoop-hdfs-zkfc start Starting Hadoop zkfc: ...
1
vote
2answers
2k views

Unable to convert HDFS from non-HA to HA

Introduction Aim: Convert HDFS from non-HA to HA. Method: According to this documentation it should be possible to convert HFDS from non- to HA by implementing following configuration: /etc/hadoop/...
1
vote
1answer
105 views

Multi domain server with dedicated SSL's HA

I am hosting a server with 150 domain names (websites), each of the ssl's requere dedicated IP address. So server windows 2008, with 150 IP addressees and 150 websites. I need to have high ...
-2
votes
1answer
247 views

Shared storage solution for Debian Wheezy [closed]

I need to setup a new infrastructure which provides high available shared storage between debian servers. Our current solution is a "clustered DRBD NFS solution". We have setup 2 virtual file ...
1
vote
3answers
100 views

Webserver failover with VMs on Two esxi 5.1

I have two server on datacenter with two websites abc.com, cde.com, and my model : ESXi 1 NIC1 113.11.11.11 from ISP NIC2 192.168.1.1 cross connect NIC2 ESXi2 VM CentOS6 ...
1
vote
1answer
498 views

MSTDC in SQL Server 2012 - Windows Server 2012 R2 with high availability

We had implemented SQL Server High Availability on two physical servers over the VPN network. SQL Server 2012, Windows Server 2012 R2. It was noted that, Distributed Transaction was working perfectly ...