Hot Failback - Hot Migration for your Virtual Machines
by Virtiant Team, on Apr 6, 2018 4:02:43 PM
Read Time: 4 minutes
The critical aspect of running today’s world-class infrastructure comes down to one simple issue, downtime. We liken it to being the power company. No one really cares about it until they flip the switch and the lights don’t come on.
So it is with infrastructure. End Users merrily traverse applications and access data without a care in the world until it becomes unavailable. That’s when the “IT” hits the fan. It’s times like these that you will be grateful for having a Hot Failback Back into your production environment from your disaster recovery site when you are in the process of recovering from a disruption
Hot versus Cold Migration
With the evolution of virtual technologies, gone are the days of having to completely rebuild physical equipment when a server goes down. The ability to quickly migrate virtual machines is one of the many benefits of this technology. There are two primary types of migration, hot and cold.
Cold migration is only somewhat removed from its older cousin, the physical rebuild. With this type of migration, you would stop the processing of applications and operating systems on your virtual machines before you move or transfer them to other physical host machines. With this method, the virtual machines do not have to be on shared storage. This type of migration also allows you to move any associated disks from one datastore to another. One drawback, especially in regards of minimizing downtime, is that the virtual machines to be migrated have to be powered down before beginning the migration process.
On the other hand, when you transfer the VM to another physical host without stopping the operating system and applications during recovery, you are actually performing a hot migration. This migration can allow you to return to your production environment and continuously run your production application with minimal if any downtime after an IT disruption
Types of VM Hot Migration
There are several different migration functions that can be accomplished including:
- Migrating just the compute resource – With this migration, you are moving the virtual machine to another computing resource, such as a host but not moving its storage.
- Migrating just the storage – Conversely, with this type you are moving the VM and its disk files from one datastore to another while the VM is still running.
- Migrating both compute and storage – This involves migrating a virtual machine to another host as well as moving the disk or virtual machine folder to another datastore.
- Migrate to another virtual switch – This type of migration allows you to move VMs without having to reconfigure the network.
- Migrate to another data center –This allows you to change the data center of a virtual machine. You can also move virtual machines between instances that are a long distance from each other.
The Benefits of Hot Failback
Of course, the primary benefit of utilizing hot migration in your VM environment is the ability to minimize downtime in the event of a disruption. In addition to continuous up-time, however, hot migration can also be beneficial in other areas such as:
- Facilitate server maintenance – You can move your VM off of existing arrays to perform routine maintenance or to install patches. In addition, you can to optimize disks performance, or change disk types, allowing you to optimize disk utilization.
- Dynamically balances workloads – This will ensure that your physical servers continue running at optimal levels.
- Provides a safeguard for underperforming servers – This will prevent an interruption to the production environment by servers that are reaching failure thresholds.
- Location independent – Whether you are failing over to commodity hardware in the same physical location or migrating to a data center halfway across the country, hot migration can handle it with relative ease.
Hot Failback for Continued Run
In the event of everyday IT disasters, such as server failures, human error, or ransomware attack, you need to be able to run your production environment from a readily available solution. Your users and your business simply cannot tolerate extended downtime. In today’s world downtime equals lost revenue. Based on research from 2016, the average hour of downtime costs to companies is roughly $160,000.
Downtime is not just an issue associated with a large-scale disaster. In fact, only about 5% of all IT disruptions are caused by major disasters such as hurricanes and earthquakes. That means that 95% of the IT disruptions that you will face as an IT manager are of the everyday variety. In order to defeat these disruptions, your Plan B needs to be a readily available solution so you can return to operations with a near zero RTO.
At Virtiant, we offer DR solutions that are available to spin-up at a moment’s notice. These standalone platforms sit adjacent to your primary infrastructure but are capable of running independently. You can also select from the options of on-premise, cloud-based or hybrid. When disruptions occur, this all in one solution can quickly and easily take over allowing you to focus on running your production environment. Faced with mounting pressure to maximize uptime, hot migration is a critical component of making that resilient solution a reality.