Exam Professional Cloud Developer topic 1 question 68 discussion

B(maxSurge = 0, maxUnavailable = 1)

"number of instances should not increase" B would be correct

maxSurge = 0, maxUnavailable = 1)

The correct answer is A. Perform a rolling-action with maxSurge set to 1, maxUnavailable set to 0. Here's why: Rolling Update: A rolling update is the best approach for deploying new versions of your application to a managed instance group while minimizing downtime and ensuring a smooth transition. maxSurge : This parameter controls the maximum number of instances that can be added to the group during the update. Setting maxSurge to 1 means that only one additional instance will be created beyond the target size of the group. This helps to minimize costs by avoiding unnecessary instance creation. maxUnavailable : This parameter controls the maximum number of instances that can be taken offline during the update. Setting maxUnavailable to 0 ensures that no existing instances are taken offline until the newly created instance is healthy. This guarantees that the deployment only continues if the new instance is healthy.

Here's the reasoning: maxSurge: This parameter determines the number of additional instances that can be created above the target size of the instance group during the update. Setting maxSurge to 1 allows the instance group to create one extra instance beyond its target size. This extra instance is used to start a new version of your application, ensuring that there's always a running instance during the update process. maxUnavailable: This parameter specifies the number of instances that can be unavailable at any time during the update. Setting maxUnavailable to 0 ensures that there is no reduction in the number of available instances below the target size during the update process.

maxSurge controls in a rolling update how many resources can be added above threshold of the MIG (managed instance group), while maxUnavailable controls the max number of instances that can be taken offline during update at the same time

the correct answer is A i think If you do not want any unavailable machines during an update, set the maxUnavailable value to 0 and the maxSurge value to greater than 0. With these settings, Compute Engine removes each old machine only after its replacement new machine is created and running. https://cloud.google.com/compute/docs/instance-groups/rolling-out-updates-to-managed-instance-groups#max_surge

Option A is best suited here as if we go with option B it does not ensures that deployment only continue if the new instance is healthy.

The correct answer is A. Performing a rolling update with maxSurge set to 1 and maxUnavailable set to 0 ensures that the deployment only continues if the new instance is healthy. The maxSurge parameter ensures that only one new instance is created at a time, while the maxUnavailable parameter ensures that the number of healthy instances does not decrease during the deployment. This will minimize costs by not creating unnecessary instances and will also ensure that the deployment is safe and does not impact the application's availability. Option B is incorrect because setting maxUnavailable to 1 would mean that one instance will be taken offline at a time, which could impact the application's availability during the deployment. Options C and D are incorrect because maxHealthy and maxUnhealthy are not valid parameters for a rolling update.

the correct answers is A

the correct answer would be A. Perform a rolling-action with maxSurge set to 1, maxUnavailable set to 0. This will minimize costs by only creating one new instance at a time, and will only continue the deployment if the new instance is healthy, ensuring a consistent latency experience for end users. https://cloud.google.com/compute/docs/instance-groups/rolling-out-updates-to-managed-instance-groups#max_surge

This is the best site here. https://tech-lab.sios.jp/archives/18553 The site is in Japanese, so please translate and read it.

B is correct

maxSurge specifies the maximum number (or percentage) of pods above the specified number of replicas (is the maximum number of new pods that will be created at a time) and maxUnavailable is the maximum number of old pods that will be deleted at a time. maxSurge = 0 would mean no extra pods with be created.

i'll go with A( number of instances should not increase--- for this number shouldn't increase than target size i think, it doesn't mean no new instances should be created, they are asking in question, like when new instance is being created, so surge >0,) https://cloud.google.com/compute/docs/instance-groups/rolling-out-updates-to-managed-instance-groups#max_unavailable If you do not want any unavailable machines during an update, set the maxUnavailable value to 0 and the maxSurge value to greater than 0. With these settings, Compute Engine removes each old machine only after its replacement new machine is created and running.

As others suggested, B is the correct option. I am adding this to highlight the community choice.

Yes it should be B as question states deployment should stop if it is unhealthy… the only we can happen is to make it to 0 for maxSurge =1