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)

1
vote
1answer
177 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
89 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
86 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
1answer
665 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 ...
3
votes
0answers
143 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
52 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
289 views

HDFS' ZKFC service unable to start

Introduction CDH4's ZooKeeper Failover Controller (ZKFC) has been installed. Starting the ZKFC service: [vagrant@localhost ~]$ sudo service hadoop-hdfs-zkfc start Starting ...
1
vote
1answer
281 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: ...
1
vote
1answer
77 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
142 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
77 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
68 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 ...
1
vote
1answer
36 views

Parallel filesystem which schedules simultaneous file requests to mutually exclusive sets of OSSs

My environment is RHEL based, interconnect is infiniband. I have some experience with Lustre. What i want to know is: Is there a parallel file-system, where if simultaneous write request arrive, ...
1
vote
1answer
134 views

How can I run a CentOS (Red Hat) cluster in degraded mode?

I've installed Red Hat's cluster software on an install of CentOS 6.5, and use it to provide redundant routing from one network to another. This works fine, and I have a pair of boxes providing the ...
2
votes
1answer
923 views

multicast address use in corosync

I'm wondering about the purpose of the multicast address in the corosync messaging software : Since we have to bind each net interface with an IP address and a specific port, and each ring communicate ...
1
vote
0answers
183 views

Most efficient way to setup massive high-availability storage in Azure to work with multiple VMs?

I'm looking into various options for setting up massive high-availability storage in Windows Azure, to use together with my Azure VMs. The VMs need to be able to work with the storage as if were a ...
0
votes
1answer
589 views

SQL Server Virtual Network Name Change Error

I am in the process of configuring a two-node failover cluster for a migration project. We are transitioning a stand-alone SQL Server to a cluster. Environment: 2x nodes with Windows Server 2012 R2 ...
-2
votes
3answers
93 views

Options for high-availability of a smallish website? [closed]

I'm running a website that gets ~1500 visitors a day. It's not a ton, but I want to make sure this site stays up nevertheless. Currently, we're hosted on a shared hosting provider and the site has ...
2
votes
4answers
555 views

new hyper V High Avaliability setup and SMB 3.0 storage

I am looking at building an new 2012 R2 with Hyper V setup, everything has to be HP hardware. 2x HyperV 2012 R2 servers running 20-30 VMs. These will be dual 6 core xeons with 128gb of ram. 2x 2012 ...
0
votes
2answers
155 views

Firewall high availability

Context: My company is on the verge of a major network improvement, we will expand our network to remote offices via radio bridges. The firewall will be handling: 3 mission critical networks 3 non ...
0
votes
1answer
116 views

VMware ESX 3.x: How to connect two ESX server to a single VMFS datastore on SAN

I'm generally a networking guy but I'm trying to learn VMware. I'm running two ESX 3.x servers with virtual center. I know that it is possible to create redundancy or high availability by configuring ...
3
votes
1answer
699 views

SonicWALL HA w/ Dual WAN HSRP from two redundant switches

We're adding two SonicWALL NSA 2600 firewalls to our current setup. We currently get two WAN connections from two separate Cisco routers running on the same external subnet with what I believe is ...
0
votes
0answers
119 views

High availability MySQL with HA Proxy failover

I am looking to load balance a Percona cluster behind two HA Proxy nodes with failover (using keepalived) so there is no single point of failure. I have HA Proxy already setup with keepalived using a ...
2
votes
1answer
483 views

NFS failover fails with stale file handles while migrating resources

Running into a bit of a problem here , I set up two servers ( Centos 6 ) with Glusterfs and a shared directory between them, I have moved the nfs directory to the shared Gluster folder and have ...
1
vote
0answers
67 views

Getting the DB2 Resource online in Failover Cluster

I'm using DB2 10.1 Enterprise Server Edition on Windows Server 2012 R2 After adding the DB2 resource to the cluster using the db2wolfi command, I go to the resources tab which is in the cluster ...
1
vote
1answer
832 views

Any problems with having an active/active HAProxy setup with Keepalived

Apologies if this has been asked before, but I can't seem to find much on it. We're going to be using HAProxy to load balance our MariaDB Galera Cluster. All the articles/tutorials I have seen on ...
4
votes
1answer
133 views

Regarding High Availability for MSSQL Server

Already used in MySQL : Real Time Replication (synchronization) between primary and secondary server is done using master and slave commands. So What is the equivalent feature for MsSQL. Which ...
0
votes
2answers
105 views

how to recover from a failed web server or reverse proxy

I have the following setup in my datacenter. Global LB --> HA proxy (2 instances on different servers via VRRP, performs HTTPS termination, acts as reverse proxy) ---> Nginx(2 instances on different ...
0
votes
0answers
75 views

Error when enabling HA on Xen Server

We have 4 Xen servers - 6.2 build 70446c - one shared storage - accessible via NFS. We disabled HA in order to solve some issues with a live migration that was stuck. I put the master on that pool in ...
0
votes
0answers
150 views

XenServer HA with only internal storage

I am new to XenServer 6.2. I have 2 Dell machine, each with 24GB RAM, 3x600GB HDD. It is possible to run VM in XenServer on 1 machine and then replicate to another Dell machine as HA. I went through ...
0
votes
2answers
93 views

best way to load balance dual esxi

Im hosting a few websites on a single ESXi box that runs Windows Server 2008 R2 with IIS 7. Now I would like to make sure that if the host goes down, the websites will still be live, so I've ordered a ...
0
votes
0answers
159 views

Configuring VRRP with keepalived on two machines - interaction with proxy arp

Let's assume we have the following topology for our network: Host1------- Router1-------Router2----------Router3-------Host2 and we want to configure vrrp on the two hosts with keepalived so that ...
0
votes
1answer
132 views

How to implement virtual IPs on AWS?

Is it possible to create floating IPs within Amazon? More specifically within the VPC? If so, how can I do this? Their documentation doesn't seem to point me in the right direction. The best I could ...
0
votes
0answers
94 views

RabbitMQ: Every other message failing to deliver/enter into queue after high availability failover

I'm currently in the process of setting up a two node rabbitmq cluster, but i'm encountering some issues when it comes to high availability. I've got clustering set up correctly on the nodes: ...
0
votes
0answers
59 views

Drupal High-Availability solution

I am trying to create a HA environment with 2 Virtual servers (CentOS 6.5) running Drupal over CPanel. THe DNS part is already solved and the solutions I have seen in Google looks quite complex. I ...
0
votes
0answers
75 views

Running two different application servers on the same Oracle RAC database

I would like to set up a basic high availability solution for one application server (Tomcat, JBoss). Is it possible to run to clone each application server and connect clone a to node1 and clone b to ...
1
vote
1answer
361 views

LAN Redundancy - NIC, Cables + Switch?

I'm trying to move to a HA solution and would like to understand what hardware is required to have redundancy in the NICs, switch and cables. The diagrams below show how I envisage a non-redundant ...
0
votes
2answers
289 views

SQL Server Failover Cluster on Azure (HA Strategy)

In the context of SQL Server 2012 Standard Edition, is it possible to make Azure Blob storage available to a SQL Failover cluster directly as a shared SCSI resource on a Windows Cluster? An Azure blob ...
2
votes
1answer
168 views

ASA High Availability failover link configuration

According to the Cisco ASA 5500 Series Configuration Guide, Cisco's preferred method of configuring your network for ASA High Availability is as such: They have two switches on External, two ...
0
votes
0answers
389 views

keepalived - random re-elections

We have set up 3 servers running keepalived . We started noticing some random re-elections occurring which we can't explain so I cam here looking for advice. Here is our configuration: MASTER: ...
5
votes
3answers
1k views

Is round-robin DNS a possible solution for high availability?

Let's say I have 2 IPs for a given domain (round-robin DNS). If one the IPs becomes unresponsive, will clients try to connect to the other IP? or they will just fail to establish comunication with the ...
6
votes
1answer
2k views

Why doesn't VMWare DRS automatically migrate VMs when a host is put in maintenance mode?

We have 4 ESXi 5.0 hosts in a VMWare cluster on shared storage (NFS) with DRS and HA on. We want to perform a memory upgrade on one of the hosts. We put that host in maintenance mode but DRS did not ...
3
votes
1answer
77 views

High Available SQL Server without SAN by using AlwaysOn feature

I have two Microsoft SQL Servers (v 2012) and I want to make them mirror and when one of them goes down the second one will be replaced. AlwaysOn is a new feature in SQL Server 2012 that is ...
4
votes
2answers
663 views

How to scale up a web server supporting long polling

I am planing to add more web application servers to support increasing clients, deploying HAproxy and Keepalived for load balancing and High availability. My server usage has the following ...
1
vote
1answer
103 views

Monitor a ucarp VIP using another interface

On Debian machines, I would like to setup a VIP between two nodes for a public IP, but I would like to avoid using three IP addresses to make ucarp communicate between the two nodes. Can I set it up ...
0
votes
0answers
75 views

bgp and incomming requests

I have IP pool, 2 providers and BGP on RouterBoard. First provider is default. Second is backup. If first provider falls - outgoing connections works on second. But incoming still routed to broken ...
2
votes
0answers
68 views

Multiple httpd with JBoss cluster: provide httpd HA

I have a working configuration like this: +-----+ +-----+ +-----+ +-----+ | i1 | | i2 | | i3 | ... | in | JBoss Cluster +--+--+ +--+--+ +--+--+ +--+--+ | ...
1
vote
1answer
171 views

Redundant web static content storage - what technologies? (small scale) [closed]

Current situation of our static web servers: 2x 2U servers full of SSDs (raid5) for storing data data are written to them only through our applications (*) huge amount of small image files (one ...
0
votes
5answers
1k views

Windows Server 2012 Hyper-V Failover Cluster + Active/Active HA storage solution

I have a question. I need to build active/active HA storage architecture, but I don't know how achieve this without expensive third party software. I have two Hyper-V hosts, each with iSCSI storage. I ...
0
votes
1answer
188 views

How to implement High Availability easily?

I have a website that is currently hosted in a single DigitalOcean region. DO are great, but occasionally they have routing issues in a region and the website goes down. The stack is very simple - a ...