Research Questions Auto Lock

The RAFT logs are stored in memory on the manager nodes.

The RAFT logs are stored on disk and not protected.

The default behaviour requires you to unlock the swarm when a new node joins the swarm cluster.

After restarting the docker service and trying to run docker service ls, you get an error “Error response from daemon: Swarm is encrypted and needs to be unlocked before it can be used. How can you solve this error?

Which command can be used to return the current key which is used inside the cluster ?

Which command can be used to enable auto lock on an existing swarm?

…. are one or more instances of a single application that runs across the Swarm Cluster.

Which command can be used to run an instance on swarm?

What is the command to run 3 instances of httpd on a swarm cluster?

What component is responsible for creating tasks in swarm?

What component is responsible for instructing a worker to run a task?

The …. assigns tasks to nodes in swarm.

The …. is used to allocate IP addresses to tasks in swarm.

Create a swarm service webapp with image httpd and expose port 8080 on host to port 80 in container.

Which command can be used to list the running service inside the swarm?

Which command can be used to list the tasks that are running as part of a specified service?

List more details about each service with a human readable format.

Which command can be used to get the logs of a swarm service?

Delete a webapp service from your cluster.

How many replicas does a service created with the command – 'docker service create webapp' have?

Which command can be used to increase the number of replicas from 2 to 4 of webapp? Select the all right answer.

The webapp:v1 had some bugs and we fixed them in webapp:v2. We want to apply webapp:v2 to webapp service. Select the right answer.

An image update operation in a swarm service happens all at once by default.

Which option of the docker service command can be used to update 4 replicas of mywebapp service at a time?

If at any time during an update a task returns FAILED, the default behaviour of the scheduler is to rollback the changes unless specified otherwise.

What option may be used to change the default behaviour of a failed task during an update in swarm?

What are the actions which can be used with <code>–update-failure-action</code> ?

After an update we realized that something is wrong with the new version and we want to revert back to the old version. How can we achieve that?

The default type of a service in docker swarm is global.

With a global service, you can specify a minimum number of replicas for the service.

A global service will always deploy exactly one instance of the application on all the nodes in the cluster.

With a global service if a node is removed from the cluster, then that instance is removed as well and is rescheduled on another available node.

Create a replicated service webapp with 2 replicas. Select the all right answer.

Deploy exactly one instance of the application on all the nodes in the cluster.

How to get the service type of webapp service? Select the all right answer.

You are required to deploy an agent of splunk on all nodes in the swarm cluster to monitor the health of the nodes and gather logs. What is the best approach to achieve this?

By default, when we create a service, the tasks may be assigned to any of these nodes without any additional considerations as long as they have sufficient hardware resources.

If you specify multiple placement constraints, the service only deploys onto nodes where they are all met.

Which option can be used to control the workload placements with the help of labels and constraints?

What is the command to deploy a service named webapp on a node which has a 'type=cpu-optimized' label.

What is the command to apply <code>’disk=ssd'</code> label to <code>worker1</code> in a swarm cluster.