VMware’s solution for high availability (HA) based on vSphere High Availability provides availability to applications running on virtual machines in a virtualised environment, regardless of the operating system (Windows, Linux, …), to automatically reduce the downtime (RTO of these applications.
What is VMware vSphere High Availability?
VMware vSphere High Availability is the ideal solution to facilitate the availability required by most of the applications that will be running inside virtual machines based on the VMware hypervisor, regardless of the operating system that we use, as long as it is compatible with the environment. It also provides cost-effective and consistent failover protection against hardware and software (operating system) outages within a virtualised IT environment. The High Availability function (High Availability) makes it possible to:
- Monitor VMware vSphere hosts and virtual machines for hardware, software, and guest operating system failures.
- Restart virtual machines on other vSphere hosts in the cluster without manual intervention when a server outage is detected, automatically.
- Reduce RTO or application downtime by automatically restarting virtual machines upon detection of an operating system failure.
Benefits of VMware vSphere High Availability
A simple way to extend and enhance the protection of your infrastructure.
This solution does not reach the complexity of other high availability systems. With just one click you can activate HA from the vSphere Client interface. With simple configuration and minimal resource requirements, it will help you:
Achieve uniform, automated protection for all applications without requiring you to modify your applications or guest operating systems.
Enable you to have a consistent first line of defence for your entire technology infrastructure.
Protect your applications that have no other failover options, which might otherwise be left unprotected.
VMware Scalability
All virtual machines and hosts will be monitored to take advantage of the high availability environment’s maturity, scalability, reliability and ease of use.
- Primary/Secondary Node Relationship: Replaces primary and secondary nodes. This new relationship model between nodes in a cluster allows availability actions to be coordinated by a single primary node, which in turn communicates all activity and status to VMware vCenter Server. This eliminates much of the planning required to design a highly available environment. Administrators don’t have to worry about whether hosts are primary or secondary nodes, or their location. This is especially significant when deploying High Availability in blade chassis and extended cluster environments.
- Support for IPv6 networks: Allows an IT department with a need for superior address space to make the most of its network infrastructure.
- Simple deployment mechanism: Promotes quick and easy completion of routine tasks, such as deploying a vSphere High Availability agent and configuring the High Availability feature.
Reliability of VMware environments
When we have a system downtime or service interruption, we should not worry about the performance of our high availability solution, it should work as autonomously as possible. According to VMWare, based on real customer feedback, the features they have added maximise confidence in High Availability. Some points of confidence are:
- Elimination of external component dependencies: High Availability does not rely on DNS resolution. This reduces the likelihood of an external component outage impacting High Availability operations.
- Multiple communication paths: High Availability nodes within a cluster can communicate across the storage subsystem as well as across the management network. Multiple communication paths increase redundancy and allow for better assessment of the health of a vSphere host and its virtual machines.
- Anti-affinity rules between virtual machines: High Availability respects the anti-affinity rules between virtual machines defined in VMware vSphere Distributed Resource Scheduler, eliminating the need to perform migrations with VMware vSphere vMotion after a failover.
vSphere Ease of Use
With a simple interface that allows you to operate and view the status of each cluster node at a glance. Error messages are easy to interpret so you can act accordingly. In the unlikely event of a problem with High Availability, you would only need to review a log file, speeding time to resolution.
More info in VMware.
