What is I/O fencing and how does it work?
By submitting your personal information, you agree that TechTarget and its partners may contact you regarding relevant content, products and special offers.
I/O fencing is used in cluster environments to make sure that two or more nodes do not access a file system simultaneously. I/O fencing is important to prevent corruption on shared storage in a cluster. It is called I/O fencing because we can compare it to putting a fence between the node that wants to access the storage device and the storage device itself. There are two common methods to prevent this access.STONITH (shoot the other node in the head) is a technique that automatically powers down a node that is not working correctly to prevent access to a shared resource. This may seem like a rough method to shut down computers, but it is better to shut down a cluster node than to spend hours recovering a corrupted file system because multiple nodes were trying to access it simultaneously. The other method, called data-based fencing, works by maintaining a list of nodes that should be allowed to access a shared device. If a node is not on the list, it will not be allowed to access the device. I/O fencing is needed in any situation where high availability is offered and where multiple hosts could potentially write to the same file system simultaneously.
Dig Deeper on Virtualized clusters and high-performance computing
Related Q&A from Sander van Vugt
As it is with other cloud platforms, autoscaling in OpenStack is important to meet changing workload demands. Here's how to enable that process with ...continue reading
Ceph object storage performance is largely based on network speed, but journal disks and the right file system for object storage devices also play a...continue reading
Integrating Ceph and Windows isn't as straightforward as connecting Ceph to Linux machines. You'll need a Ceph Gateway or SUSE Enterprise Storage to ...continue reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.