When managing a website or web-based application downtime is one of the worst things that can happen to you. Unfortunately, achieving those elusive five nines of uptime means having to set up and maintain lots of complicated and expensive systems - or at least it used to.
We have developed the Cross Site Cluster service using all the technology and infrastructure we perfected to keep our data centres online and highly available. Our solution is an all-in-one package that can be easily deployed to give you effortless, geographically separated, high-availability without any of the hassles.
All you need is a server in both of our data centres and the Cross Site Cluster will monitor all of your servers and instantly re-route all your traffic to the online server should a problem be detected. You can be confident that your web presence will stay online no matter what happens to your servers providing the first step in defence for business continuity.
This allows you to operate even during maintenance windows. Now, taking a server offline won't take you offline.
How does a Cross Site Cluster work?
Routes are advertised in conjunction with suitable, self-configurable health checks carried out by our dedicated, redundant monitor nodes. If, for example, our monitors notice that a master service has disappeared during a health check, such as a server crash or a network connectivity issues, the routes are changed to direct traffic to the failover service resulting in minimal downtime.
All participating services within the Cross Site Cluster are assigned the same IP address and are given a routing preference. BGP will route traffic according to preference allowing a higher preference to be set for the master service. In the case of this service failing or network connectivity being lost to that datacentre, traffic will then flow to the service assigned with the lower preference.
How do I configure a Cross Site Cluster?
Once the Cross Site Cluster has been deployed you will have access to the management tools in your Memset control panel. From here you will be able to add and manage your servers; you can find more information about this in our Cross Site Cluster documentation.
What is Live / Standby?
Traffic will be directed to a single live site, unless it fails its regular health check or there is an issue with the network connectivity. If this happens then the traffic will automatically be routed to the standby site, and once connectivity has been restored to the original live site all traffic will be routed back to it.
Benefits of Live / Standby?
Only a single IP address is required, which is configured to both data centers ensuring geographic redundancy.
It is a cost-effective way to create a cross site cluster (or cross site server group) in order to provide disaster recovery and automatic failover.
What is Live / Live?
There are two live sites (A and B say). Typically, traffic will flow equally to A and B, however should there be an issue on either A or B ALL traffic will automatically be rerouted to the other site.
The Live / Live solution works best with multiple external IP addresses. Essentially this creates two Live / Standby clusters which have equal priority. In this set up one cluster will have A as Live and B as standby while the other has B as live and A as standby. Both IPs are then entered into the DNS, round-robin style, commanding traffic to flow evenly between the sites.
Benefits of Live / Live?
As with the Live / Standby solution it provides disaster recovery and automated failovers, additionally it provides load distribution due to the round-robin DNS. This means that both of your servers are being utilised rather than one being in standby the majority of the time.
You can configure a Cross Site Cluster on your Memset infrastructure if you have a server in multiple Memset data centres. Alternatively, you can set up a free no obligation consultation with a technical expert to find the perfect solution for you.