Reliability vs Resiliency ?

Question

In the page , https://learn.microsoft.com/en-us/training/modules/describe-benefits-use-cloud-services/3-reliability-predictability-cloud

It says "Reliability is the ability of a system to recover from failures and continue to function". Isn't that called as Resiliency?

Reliability

Reliability is a measure of how likely a system is to fail. It is typically expressed as a probability or a percentage. For example, a system with a reliability of 99% is expected to fail once in every 100 attempts.

Resiliency

Resiliency is a measure of how well a system can recover from a failure. It is typically expressed as a time or a percentage. For example, a system with a resiliency of 1 hour is expected to recover from a failure within 1 hour.

This question is related to the following Learning Module

Answer 1

In essence, reliability assesses the likelihood of failure, while resiliency assesses the system's ability to withstand and recover from failures. While both concepts are related to the robustness of a system, they address different aspects and are equally important for ensuring the overall stability and performance of the system.

1. Reliability: Reliability is primarily concerned with the probability of a system experiencing a failure over a given period. It measures the stability and consistency of a system's performance, indicating how often the system is expected to fail. Reliability is typically expressed as a probability or percentage, representing the likelihood of failure within a specific timeframe. For example, if a system has a reliability of 99%, it means that there is a 1% chance of the system failing in a given set of conditions or operations.
2. Resiliency: Resiliency focuses on the ability of a system to recover from failures and continue functioning despite disruptions. It measures how quickly and effectively a system can bounce back from adverse events or failures, minimizing downtime and impact on operations. Resiliency is typically expressed as a measure of time or percentage, indicating the time it takes for the system to recover from a failure or the percentage of operations that can be successfully completed despite failures. For example, if a system has a resiliency of 1 hour, it means that it can recover from a failure within one hour, ensuring minimal disruption to operations.

---

If the above response helps answer your question, remember to "Accept Answer" so that others in the community facing similar issues can easily find the solution. Your contribution is highly appreciated.

hth

Marcin