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Questions tagged [high-availability]

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

High availability is an architectural consideration often involving degrees of redundancy to insure availability in case of system or component failure. Highly available systems are commonly implemented in situations where the risk outweighs the cost.

Best practices such as change control, standardized procedures, and monitoring can also enable high availability.

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Insufficient channel capacity of 1GBit

There is a Caching Server (Varnish): it receives data from Amazon S3 on request, saves it for some time and gives it to the client. We have encountered the problem of insufficient channel capacity of 1GBit. Peak load within 4 hours completely chokes…
Roman Skvazh
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Solution for two-way file-system transparent solution

I need to implement some sort of HA setup where 2 servers need to be able to always be in sync, no matter on which one you write on. The DB part can be covered by a master-master replication setup. However, when it comes to files and content I…
cbaltatescu
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ucarp: promote slave to master

I have got ucarp working on my two ubuntu servers. Apache, Postfix, Dovecot are working in HA mode so if one host goes down the other automatically takes over. My first problem is that I don't know how can I manually promote the slave to…
Jure1873
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Scaling server cluster setup

I'm in middle of re-building a website that currently gets about 4mil+ visitors a month (and that's going straight up lately). It's currently being run and hosted by an external company, but we're dumping them so I need to design hosting. I'm…
yrosen
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Highly available ZFS SAN/NAS with SMB and NFS

I've currently got a storage server running Oracle Solaris Express 11 with 12x1tb disks. It currently provides two functions: 1) Providing a datastore for a small vSphere 4.1 farm over NFS and 2) providing a network share for a team over SMB. The…
growse
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Is this a reasonable architecture for a newspaper site?

We run a newspaper-style site and are consolidating our architecture from one that grew amorphously into a more scalable, resiliant solution. I was thinking of the following: internet | h/w firewall | h/w load balancer | | |…
timmy
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High Availability with 2 servers?

Is it possible to have a high availability setup with 2 servers? Running Windows Web Server 2008 and MSSQL Web Edition (as I know Express isn't supported)? Getting to the point where our one dedicated server needs scaled out and going to a second…
Tom R
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Providing high availability and failover using MySQL on EC2

I would like to have a highly-available MySQL system, with automatic failover, running on Amazon EC2 instances. The standard approach to solving this is problem Heartbeat + DRBD, but I've found a lot of posts suggesting DRBD doesn't work on EC2,…
crb
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High availability MariaDB only two servers

I'm not worried about split brain since the connection between the two servers is solid (and because I don't have a third machine) I want to have some MariaDB replication with automatic failover so even if one database dies, it continues working.…
forkwasher
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HA configuration for KVM machines installed on shared iSCSI storage

My requirement is to provide HA to a Zimbra Server. We want Zimbra files to be installed in a Netapp SAN which is providing around 5.7 TB as a SAN iSCI Drive. Since Netapp comes in with Dual Controller and stable performance, we are unlikely to have…
John The Hacker
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High availability for ceph storage?

Do ceph have high availability, I config 2 node like this cluster: id: 07df97db-f315-4c78-9d2a-ab85007a1856 health: HEALTH_WARN Reduced data availability: 32 pgs inactive Degraded data redundancy: 374/590…
Lê Minh Quân
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Redis sentinel: force switch to another master

Context: I have 3 redis nodes, and 3 sentinels. The failover works properly. When I'm taking the master down, another master is elected. Need: I need a way to test the behavior, to make sure everything works as expected. I wish I could force the…
aspyct
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Azure high availability solution with synchronization of website and SQL server data

We have a web solution that we sell and it comes with 1 dedicated Azure VM containing everything it requires to run the application: ASP.NET web application Production environment QA environment SQL server containing data for both PROD and QA…
Zeep
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Site-aware cluster migrates VMs to random nodes, not to the preffered site

We have 2 physical host, 4 virtual-node (HyperV Server VMs, 2 on each host) cluster which is running some nested test VMs (using mentioned HyperV Server). In short it is ment as a lab environment where we are trying to replicate 2 rack (where each…
Jon
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Apache Failed to Start in Pacemaker

I am using Pacemaker with Corosync to set up a basic Apache HA cluster with 3 nodes running CentOS. For some reasons, I cannot get the apache resource started in pcs. Cluster IP: 192.168.200.40 # pcs resource show ClusterIP Resource: ClusterIP…
cody
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