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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Is there a way to force heartbeat to add new ip addresses to the system without a full restart?

We utilize heartbeat for High Availability. I'd like to add an additional ip address to the heartbeat cluster, but I don't want to do a full restart of the cluster in the process. Is there a signal ...
3
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3answers
667 views

Does it work to run mysql with the data directory on a CephFS mount?

We have a database cluster that uses MySQL on DRBD with Pacemaker+Corosync, which is great. My question is whether it is possible (and whether anyone has been successful) to mount a CephFS drive to ...
2
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1answer
1k 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 ...
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0answers
201 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
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1answer
757 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
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4answers
677 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
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2answers
191 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 ...
-2
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3answers
95 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
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1answer
565 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 ...
0
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1answer
130 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 ...
0
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0answers
131 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 ...
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0answers
88 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 ...
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1answer
1k 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 ...
6
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2answers
7k views

What is the difference between keepalive and heartbeat?

I want to structure a high available server cluster . Now I want to know detail about keepalive and heartbeat, what is the difference between both, and How to choice one.
4
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3answers
1k views

How to make cronjobs high available?

What would be a good solution to make a failover pair that has multiple cronjobs running avoid running the processes twice? Either in failover, or by dividing the jobs between them, and of course ...
8
votes
7answers
4k views

How to perform cron jobs failover?

Using two Debian servers, I need to setup a strong failover environment for cron jobs that can be only called on one server at a time. Moving a file in /etc/cron.d should do the trick, but is there ...
4
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1answer
193 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
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2answers
120 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
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0answers
84 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 ...
4
votes
1answer
910 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 ...
0
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4answers
2k views

What are the ways to build a failover cluster?

I have a task where I need to build a failover cluster in two cases: first with servers on Red Hat Enterprise 5.1 and second with SUSE Linux Enterprise 11 SP1. Both cases have SAN. I know there are ...
0
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0answers
168 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
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1answer
70 views

Make keepalived send 0 priority when going to FAULT state

When stopping (service keepalived stop), keepalived does send the priority 0 adverts so the backup server takes over almost immediately. However, when it goes to fault mode (check script returns not ...
0
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2answers
100 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
1answer
172 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 ...
2
votes
1answer
320 views

Simple redundancy setup using two servers in two different datacenters? [closed]

Scope of the question This question is solely about getting a client requesting a domain: example.com to one of the two available servers. How it is handled from there on, is another problem to solve ...
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 ...
1
vote
1answer
122 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 ...
1
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1answer
399 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 ...
2
votes
1answer
184 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 ...
1
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2answers
996 views

High availability LDAPS with Fedora Directory Server

I've been asked to set up a HA LDAP architecture using Fedora Directory Server - the company currebnly uses Sun DS but wants to move away from Sun. I want to use a network hardware loadbalancer ...
5
votes
4answers
7k views

SonicWall “gotchas”?

We're looking to move away from PFSense and CARP to a pair of SonicWall NSA 24001 configured in Active/Passive for High Availability. I've never dealt with SonicWall before, so is there anything I ...
0
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0answers
439 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: ...
0
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2answers
107 views

Why does DRBD infrastructure resyncs whole partition several times a day

I have a Primary/Secondary 2 nodes DRBD setting as shown global { usage-count no; } common { syncer { rate 4M; } } resource r0 { protocol B; startup { wfc-timeout 15; ...
4
votes
2answers
772 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 ...
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
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1answer
81 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 ...
1
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1answer
372 views

SBD killing both cluster nodes when there are even small SAN network problems

I am having problems with stonith SBD in a openais-based cluster. Some background: The active/passive cluster has two nodes, node1 and node2. They are configured to provide an NFS service to users. ...
0
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0answers
87 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
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0answers
80 views

Multiple httpd with JBoss cluster: provide httpd HA

I have a working configuration like this: +-----+ +-----+ +-----+ +-----+ | i1 | | i2 | | i3 | ... | in | JBoss Cluster +--+--+ +--+--+ +--+--+ +--+--+ | ...
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 ...
1
vote
1answer
184 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
1answer
127 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 ...
0
votes
1answer
226 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 ...
1
vote
0answers
82 views

HP Blade based georedundant configuration / IRF

I'm planning to deploy 2 georedundant server farms. We chose HP Blade system. Every site would consist of: 1 x C3000 enclosure 4 x BL460c servers equiped additionally with 554M mezzanine (to have 4 ...
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0answers
412 views

Memcached and repcached not replicating 2 master servers

I have memcached-1.2.8-repcached-2.2 installed on memcached on centos. They install went great and when i start memcached i get: replication: connect (peer=192.168.1.2:11212) replication: marugoto ...
1
vote
1answer
141 views

(simple) linux HA with vmware vsphere?

I hope my upcoming question is specific enough, and you are able and willing to support :-) We have several openSUSE VMs in an ESX-Cluster (three ESX-Servers) with an attached iSCSI-SAN. All of ...
2
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0answers
319 views

TeamCity (or Jenkins) with Cluster/Replicated servers

We use Team City 7 for Continuous Intergration. Sometimes I need to bring down the server for maintenance which stirs up complaints. Is anyone using a cluster for these types of servers where there ...
2
votes
1answer
168 views

Fault-tolerant network access to redundant storage in a heterogeneous environment (including Windows)?

We are facing a design "challenge" where we are required to set up a storage solution with the following properties: What we need HA a scalable storage backend offline/disconnected operation on ...
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1answer
110 views

Remus or alternatives

Is it possible to set up Remus to act as a high availability server across 3 locations. Has anyone set up something like that. That is A would be main site, which would have an HA set up at B, and C ...