Every data center, application environment, enterprise organization, and cloud provider would probably like nothing better than to achieve “zero downtime” for all of their operations. High availability (HA) architecture can provide the flexibility and reliability that you’re seeking for backup and recovery solutions.
So, what stops organizations like yours from achieving this goal? Here are a few factors that may be impeding your progress:
- Ever increasing data center complexity: As data centers become more virtualized and software-defined, increased system complexity can make it hard to plan for and avoid all sources of potential downtime. In contrast to the early days of client/server operations, there are now many more layers of systems and software that exist between end users and the underlying physical infrastructure upon which they rely. Planning redundancy and failover for every potential eventuality, on every layer of the stack, can be a daunting undertaking, even for the most experienced data center managers.
- Escalating operational costs. Beyond the new layers of complexity, the quest to achieve zero downtime can become fairly expensive. Careful consideration must be made to the value of uptime for each application environment (and each layer above or below it).
High Availability Architecture Solutions
At WEI, we are accustomed to working closely with organizations to improve their disaster recovery and high availability goals. In the process, we often witness various uses of primary and secondary (or remote) data centers. Here are four different HA architectures we often see in the field:
- Bronze HA: Strong primary, “Basic” remote data center
- Silver HA: Strong primary, “Standby” remote data center
- Gold HA: Strong primary, “Active” remote data center
- Hybrid HA: When the Cloud is your remote data center
Read on for a closer look at the goals of each of these HA architectures as well as some of its potential drawbacks.
Bronze: Strong Primary, “Basic” Remote Data Center
A low-cost high availability solution, the goal of this approach is to avoid disruption and/or recover seamlessly (and with minimal end user notice) from most localized causes of potential downtime within the primary data center. The Bronze-level HA architecture puts more emphasis on HA investment within the primary data center. While a secondary data center is used, it is typically restricted to that of a secondary, offsite location for digital backups. In the event of a regional or site-wide failure, the organization knows it can access its offsite backups, but recognizes it will take considerable time before all systems are back into operation. For site-wide or regional events that require access to the secondary data center, application recovery from remote backup copies can range from 1 to 30 days.
Silver HA Architecture: Strong Primary, “Standby” Remote Data Center
A Silver-level high availability architecture emphasizes strong HA investment within the primary data center. How it differs from Bronze however, is that it also puts more investment into the secondary data center’s high availability capabilities. Its purpose is to serve as a standby (passive) data center within an active/passive configuration, allowing the remote data center to “step in” and take over some form of operation in the event the primary data center becomes unavailable. In the event of a site-wide failure at the primary data center, silver-level HA architecture also offers the ability to manually failover to the second data center and/or recover and resume operations as the organization waits for the primary data center to go back online. It’s a medium cost solution compared to Bronze HA architecture.
Gold HA Architecture: Strong Primary, “Active” Remote Data Center
The most expensive HA solution, a Gold-level high availability architecture aims to avoid disruption and/or recover seamlessly, with minimal end user notice, from most localized causes of potential downtime. It differs from Bronze and Silver-level architectures because the secondary data center is often a direct replica of the primary data center.
As opposed to standing by passively and waiting for the primary data center to have problems or experienced an unplanned outage, a Gold-level HA architecture uses the secondary data center as an active component that remains up to date on most of the recent application changes or transactions. This is part of what’s known as an “active/active” configuration (vs. an active/passive configuration found in a Silver HA architecture). Using more automation and more technology, this remote data center can much more quickly act in the event the primary data center fails. Use this data protection solution for workloads that are crucial to business operations or for classified information you need readily available.
Hybrid HA Architecture: When “The Cloud” is Your Remote Data Center
This type of hybrid availability architecture is represented, to some degree, in the last three architecture levels. Everywhere a secondary data center is used, it’s possible to now perform that function via a cloud provider. Typically, this function will be performed with the use of virtual systems not owned by a company, but leased from the cloud provider, as in a utility model.
Want to know more about differing high availability architectures and learn ways they can benefit your organization’s disaster recovery efforts? Contact the WEI team for assistance in securing your enterprise’s data and operations.
