Describe each of the following components in Ansible, including the relationship between them:
Task
Module
Play
Playbook
Role
How Ansible is different from other Automation tools?
Ansible is:
Agentless
Minimal run requirements (Python & SSH) and simple to use
Default mode is "push" (it supports also pull)
Focus on simpleness and ease-of-use
True or False? Ansible follows the mutable infrastructure paradigm
True.
True or False? Ansible uses declarative style to describe the expected end state False. It uses a procedural style.What kind of automation you wouldn't do with Ansible and why?
While it's possible to provision resources with Ansible, some prefer to use tools that follow immutable infrastructure paradigm. Ansible doesn't saves state by default. So a task that creates 5 instances for example, when executed again will create additional 5 instances (unless additional check is implemented) while other tools will check if 5 instances exist. If only 4 exist, additional instance will be created.
What is an inventory file and how do you define one?
An inventory file defines hosts and/or groups of hosts on which Ansible tasks executed upon.
What is a dynamic inventory file? When you would use one?
A dynamic inventory file tracks hosts from one or more sources like cloud providers and CMDB systems.
You should use one when using external sources and especially when the hosts in your environment are being automatically spun up and shut down, without you tracking every change in these sources.
How do you list all modules and how can you see details on a specific module?
Ansible online docs
ansible-doc -l for list of modules and ansible [module_name] for detailed information on a specific module
Write a task to create the directory ‘/tmp/new_directory’
- name: Create a new directory
file:
path: "/tmp/new_directory"
state: directory
You want to run Ansible playbook only on specific minor version of your OS, how would you achieve that? What the "become" directive used for in Ansible? What are facts? How to see all the facts of a certain host? What would be the result of the following play?
---
- name: Print information about my host
hosts: localhost
gather_facts: 'no'
tasks:
- name: Print hostname
debug:
msg: "It's me, {{ ansible_hostname }}"
When given a written code, always inspect it thoroughly. If your answer is “this will fail” then you are right. We are using a fact (ansible_hostname), which is a gathered piece of information from the host we are running on. But in this case, we disabled facts gathering (gather_facts: no) so the variable would be undefined which will result in failure.
What would be the result of running the following task? How to fix it?
Which Ansible best practices are you familiar with?. Name at least three Explain the directory layout of an Ansible role What 'blocks' are used for in Ansible? How do you handle errors in Ansible? You would like to run a certain command if a task fails. How would you achieve that? Write a playbook to install ‘zlib’ and ‘vim’ on all hosts if the file ‘/tmp/mario’ exists on the system.
---
- hosts: all
vars:
mario_file: /tmp/mario
package_list:
- 'zlib'
- 'vim'
tasks:
- name: Check for mario file
stat:
path: "{{ mario_file }}"
register: mario_f
- name: Install zlib and vim if mario file exists
become: "yes"
package:
name: "{{ item }}"
state: present
with_items: "{{ package_list }}"
when: mario_f.stat.exists
Write a single task that verifies all the files in files_list variable exist on the host
# {{ ansible_managed }}
I'm {{ ansible_hostname }} and my operating system is {{ ansible_distribution }
The variable 'whoami' defined in the following places:
role defaults -> whoami: mario
extra vars (variables you pass to Ansible CLI with -e) -> whoami: toad
host facts -> whoami: luigi
inventory variables (doesn’t matter which type) -> whoami: browser
According to variable precedence, which one will be used?
For each of the following statements determine if it's true or false:
A module is a collection of tasks
It’s better to use shell or command instead of a specific module
Host facts override play variables
A role might include the following: vars, meta, and handlers
Dynamic inventory is generated by extracting information from external sources
It’s a best practice to use indention of 2 spaces instead of 4
‘notify’ used to trigger handlers
This “hosts: all:!controllers” means ‘run only on controllers group hosts
Explain the Diffrence between Forks and Serial & Throttle.
Serial is like running the playbook for each host in turn, waiting for completion of the complete playbook before moving on to the next host. forks=1 means run the first task in a play on one host before running the same task on the next host, so the first task will be run for each host before the next task is touched. Default fork is 5 in ansible.
[defaults]
forks = 30
- hosts: webservers
serial: 1
tasks:
- name: ...
Ansible also supports throttle This keyword limits the number of workers up to the maximum set via the forks setting or serial. This can be useful in restricting tasks that may be CPU-intensive or interact with a rate-limiting API
What is ansible-pull? How is it different from how ansible-playbook works? What is Ansible Vault? Demonstrate each of the following with Ansible:
Conditionals
Loops
What are filters? Do you have experience with writing filters? Write a filter to capitalize a string
def cap(self, string):
return string.capitalize()
You would like to run a task only if previous task changed anything. How would you achieve that? What are callback plugins? What can you achieve by using callback plugins? What is Ansible Collections? File '/tmp/exercise' includes the following content
How do you test your Ansible based projects? What is Molecule? How does it works? You run Ansibe tests and you get "idempotence test failed". What does it mean? Why idempotence is important?
Terraform
Explain what Terraform is and how does it worksWhat benefits infrastructure-as-code has?Why Terraform and not other technologies? (e.g. Ansible, Puppet, CloufFormation)True or False? Terraform follows the mutable infrastructure paradigmTrue or False? Terraform uses declarative style to describe the expected end stateExplain what is "Terraform configuration"What is HCL?Explain each of the following:
Provider
Resource
Provisioner
What terraform.tfstate file is used for?How do you rename an existing resource?Explain what the following commands do:
terraform init
terraform plan
terraform validate
terraform apply
How to write down a variable which changes by an external source or during terraform apply?Give an example of several Terraform best practicesExplain how implicit and explicit dependencies work in TerraformWhat is local-exec and remote-exec in the context of provisioners?What is a "tainted resource"?What terraform taint does?What types of variables are supported in Terraform?What is a data source? In what scenarios for example would need to use it?What are output variables and what terraform output does?Explain ModulesWhat is the Terraform Registry?Explain remote-exec and local-execExplain "Remote State". When would you use it and how?Explain "State Locking"What is the "Random" provider? What is it used forHow do you test a terraform module?Aside from .tfvars files or CLI arguments, how can you inject dependencies from other modules?
What is a Container? What is it used for?How are containers different from virtual machines (VMs)?In which scenarios would you use containers and in which you would prefer to use VMs?Explain Podman or Docker architectureDescribe in detail what happens when you run `podman/docker run hello-world`?What are `dockerd, docker-containerd, docker-runc, docker-containerd-ctr, docker-containerd-shim` ?Describe difference between cgroups and namespacesDescribe in detail what happens when you run `docker pull image:tag`?How do you run a container?What `podman commit` does?. When will you use it?How would you transfer data from one container into another?What happens to data of the container when a container exists?Explain what each of the following commands do:
docker run
docker rm
docker ps
docker pull
docker build
docker commit
How do you remove old, non running, containers?
Dockerfile
What is DockerfileWhat is the difference between ADD and COPY in Dockerfile?What is the difference between CMD and RUN in Dockerfile?Do you perform any checks or testing related to your Dockerfile?Explain what is Docker compose and what is it used forDescribe the process of using Docker ComposeExplain Docker interlockWhere can you store Docker images?What is Docker Hub?What is the difference between Docker Hub and Docker cloud?What is Docker Repository?Explain image layersWhat best practices are you familiar related to working with containers?How do you manage persistent storage in Docker?How can you connect from the inside of your container to the localhost of your host, where the container runs?How do you copy files from Docker container to the host and vice versa?
What is Kubernetes? Why organizations are using it?What is a Kubernetes Cluster?When or why NOT to use Kubernetes?
Kubernetes Nodes
What is a Node?What the master node is responsible for?What do we need the worker nodes for?What is kubectl?Which command you run to view your nodes?True or False? Every cluster must have 0 or more master nodes and at least on e workerWhat are the components of the master node?What are the components of a worker node?
Kubernetes Pod
Explain what is a podDeploy a pod called "my-pod" using the nginx:alpine imageHow many containers can a pod contain?What does it mean that "pods are ephemeral?Which command you run to view all pods running on all namespaces?How to delete a pod?
Kubernetes Deployment
What is a "Deployment" in Kubernetes?How to create a deployment?How to edit a deployment?What happens after you edit a deployment and change the image?How to delete a deployment?What happens when you delete a deployment?How make an app accessible on private or external network?
Kubernetes Service
What is a Service in Kubernetes?True or False? The lifecycle of Pods and Services isn't connected so when a pod dies, the service still staysWhat Service types are there?How to get information on a certain service?How to verify that a certain service forwards the requests to a podWhat is the difference between an external and an internal service?How to turn the following service into an external one?
What is Ingress Controller?What are some use cases for using Ingress?How to list Ingress in your namespace?What is Ingress Default Backend?How to configure a default backend?How to configure TLS with Ingress?True or False? When configuring Ingress with TLS, the Secret component must be in the same namespace as the Ingress component
Kubernetes Configuration File
Which parts a configuration file has?What is the format of a configuration file?How to get latest configuration of a deployment?Where Kubernetes gets the status data (which is added to the configuration file) from?
Kubernetes etcd
What is etcd?True or False? Etcd holds the current status of any kubernetes componentTrue or False? The API server is the only component which communicates directly with etcdTrue or False? application data is not stored in etcd
Kubernetes Namespaces
What are namespaces?Why to use namespaces? What is the problem with using one default namespace?True or False? When a namespace is deleted all resources in that namespace are not deleted but moved to another default namespaceWhat special namespaces are there by default when creating a Kubernetes cluster?What can you find in kube-system namespace?How to list all namespaces?What kube-public contains?How to get the name of the current namespace?What kube-node-lease contains?How to create a namespace?What default namespace contains?True or False? With namespaces you can limit the resources consumed by the users/teamsHow to switch to another namespace? In other words how to change active namespace?What is Resource Quota?How to create a Resource Quota?Which resources are accessible from different namespaces?Let's say you have three namespaces: x, y and z. In x namespace you have a ConfigMap referencing service in z namespace. Can you reference the ConfigMap in x namespace from y namespace?Which service and in which namespace the following file is referencing?
Which components can't be created within a namespace?How to list all the components that bound to a namespace?How to create components in a namespace?
Kubernetes Commands
What kubectl exec does?What kubectl get all does?What the command kubectl get pod does?How to see all the components of a certain application?What kubectl apply -f [file] does?What the command kubectl api-resources --namespaced=false does?How to print information on a specific pod?How to execute the command "ls" in an existing pod?How to create a service that exposes a deployment?How to create a pod and a service with one command?Describe in detail what the following command does kubectl create deployment kubernetes-httpd --image=httpdWhy to create kind deployment, if pods can be launched with replicaset?How to scale a deployment to 8 replicas?How to get list of resources which are not in a namespace?How to delete all pods whose status is not "Running"?What kubectl logs [pod-name] command does?What kubectl describe pod [pod name] does? command does?How to display the resources usages of pods?What kubectl get componentstatus does?What is Minikube?How do you monitor your Kubernetes?You suspect one of the pods is having issues, what do you do?What the Kubernetes Scheduler does?What happens to running pods if if you stop Kubelet on the worker nodes?What happens what pods are using too much memory? (more than its limit)Describe how roll-back worksTrue or False? Memory is a compressible resource, meaning that when a container reach the memory limit, it will keep runningWhat is the control loop? How it works?
Kubernetes Operator
What is an Operator?Why do we need Operators?What components the Operator consists of?How Operator works?True or False? Kubernetes Operator used for stateful applicationsWhat is the Operator Framework?What components the Operator Framework consists of?Describe in detail what is the Operator Lifecycle ManagerWhat openshift-operator-lifecycle-manager namespace includes?What is kubconfig? What do you use it for?Can you use a Deployment for stateful applications?Explain StatefulSet
Kubernetes ReplicaSet
What is the purpose of ReplicaSet?How a ReplicaSet works?What happens when a replica dies?
Kubernetes Secrets
Explain Kubernetes SecretsHow to create a Secret from a key and value?How to create a Secret from a file?What type: Opaque in a secret file means? What other types are there?True or False? storing data in a Secret component makes it automatically securedWhat is the problem with the following Secret file:
True or False? Kubernetes provides data persistence out of the box, so when you restart a pod, data is savedExplain "Persistent Volumes". Why do we need it?True or False? Persistent Volume must be available to all nodes because the pod can restart on any of themWhat types of persistent volumes are there?What is PersistentVolumeClaim?True or False? Kubernetes manages data persistenceExplain Storage ClassesExplain "Dynamic Provisioning" and "Static Provisioning"Explain Access ModesWhat is Reclaim Policy?What reclaim policies are there?
Kubernetes Access Control
What is RBAC?Explain the Role and RoleBinding" objectsWhat is the difference between Role and ClusterRole objects?
Kubernetes Misc
Explain what Kubernetes Service Discovery meansYou have one Kubernetes cluster and multiple teams that would like to use it. You would like to limit the resources each team consumes in the cluster. Which Kubernetes concept would you use for that?What Kube Proxy does?What "Resources Quotas" are used for and how?Explain ConfigMapHow to use ConfigMaps?Trur or False? Sensitive data, like credentials, should be stored in a ConfigMapExplain "Horizontal Pod Autoscaler"When you delete a pod, is it deleted instantly? (a moment after running the command)How to delete a pod instantly?Explain Liveness probeExplain Readiness probeWhat does being cloud-native mean?Explain the pet and cattle approach of infrastructure with respect to kubernetesDescribe how you one proceeds to run a containerised web app in K8s, which should be reachable from a public URL.How would you troubleshoot your cluster if some applications are not reachable any more?Describe what CustomResourceDefinitions there are in the Kubernetes world? What they can be used for?How does scheduling work in kubernetes?How are labels and selectors used?Explain what is CronJob and what is it used forWhat QoS classes are there?Explain Labels. What are they and why would one use them?Explain SelectorsWhat is Kubeconfig?
Helm
What is Helm?Why do we need Helm? What would be the use case for using it?Explain "Helm Charts"It is said that Helm is also Templating Engine. What does it mean?What are some use cases for using Helm template file?Explain the Helm Chart Directory StructureHow do you search for charts?Is it possible to override values in values.yaml file when installing a chart?How Helm supports release management?
Submariner
Explain what is Submariner and what is it used forWhat each of the following components does?:
Lighthouse
Broker
Gateway Engine
Route Agent
Istio
What is Istio? What is it used for?
Programming
What programming language do you prefer to use for DevOps related tasks? Why specifically this one?What are static typed (or simply typed) languages?Explain expressions and statementsWhat is Object Oriented Programming? Why is it important?Explain CompositionWhat is a compiler?What is an interpreter?Are you familiar with SOLID design principles?What is YAGNI? What is your opinion on it?What is DRY? What is your opinion on it?What are the four pillars of object oriented programming?Explain recursionExplain Inversion of ControlExplain Dependency InjectionTrue or False? In Dynamically typed languages the variable type is known at run-time instead of at compile-timeExplain what are design patterns and describe three of them in detailExplain big O notationWhat is "Duck Typing"?
Common algorithms
Binary search:
How does it works?
Can you implement it? (in any language you prefer)
What is the average performance of the algorithm you wrote?
Code Review
What are your code-review best practices?Do you agree/disagree with each of the following statements and why?:
The commit message is not important. When reviewing a change/patch one should focus on the actual change
You shouldn't test your code before submitting it. This is what CI/CD exists for.
Strings
In any language you want, write a function to determine if a given string is a palindromeIn any language you want, write a function to determine if two strings are Anagrams
Integers
In any language you would like, print the numbers from 1 to a given integer. For example for input: 5, the output is: 12345
Time Complexity
Describe what would be the time complexity of the operations access, searchinsert and remove for the following data structures:What is the complexity for the best, worst and average cases of each of the following algorithms?:
Quick sort
Merge sort
Bucket Sort
Radix Sort
Data Structures & Types
Implement Stack in any language you would likeTell me everything you know about Linked ListsDescribe (no need to implement) how to detect a loop in a Linked ListImplement Hash table in any language you would likeWhat is Integer Overflow? How is it handled?Name 3 design patterns. Do you know how to implement (= provide an example) these design pattern in any language you'll choose?Given an array/list of integers, find 3 integers which are adding up to 0 (in any language you would like)
Python
What are some characteristics of the Python programming language?What built-in types Python has?What is mutability? Which of the built-in types in Python are mutable?What is a tuple in Python? What is it used for?List, like a tuple, is also used for storing multiple items. What is then, the difference between a tuple and a list?What is the result of each of the following?
1 > 2
'b' > 'a'
1 == 'one'
2 > 'one'
What is the result of of each of the following?
"abc"*3
"abc"*2.5
"abc"*2.0
"abc"*True
"abc"*False
What is the result of `bool("")`? What about `bool(" ")`? ExplainWhat is the result of running [] is not []? explain the resultImprove the following code:
char = input("Insert a character: ")
if char == "a" or char == "o" or char == "e" or char =="u" or char == "i":
print("It's a vowel!")
How to define a function with Python?In Python, functions are first-class objects. What does it mean?Explain inheritance and how to use it in PythonExplain and demonstrate class attributes & instance attributes
Python - Exceptions
What is an error? What is an exception? What types of exceptions are you familiar with?Explain Exception Handling and how to use it in PythonWhat is the result of running the following function?
Explain the following built-in functions (their purpose + use case example):
repr
any
all
What is the difference between repr function and str?What is the __call__ method?Do classes has the __call__ method as well? What for?What _ is used for in Python?Explain what is GILWhat is Lambda? How is it used?
Properties
Are there private variables in Python? How would you make an attribute of a class, private?Explain the following:
getter
setter
deleter
Explain what is @propertyHow do you swap values between two variables?Explain the following object's magic variables:
dict
Write a function to return the sum of one or more numbers. The user will decide how many numbers to usePrint the average of [2, 5, 6]. It should be rounded to 3 decimal places
Python Lists
How to add the number 2 to the list x = [1, 2, 3]How to check how many items a list contains?How to get the last element of a list?How to add the items of [1, 2, 3] to the list [4, 5, 6]?How to remove the first 3 items from a list?How do you get the maximum and minimum values from a list?How to get the top/biggest 3 items from a list?How to insert an item to the beginning of a list? What about two items?How to sort list by the length of items?Do you know what is the difference between list.sort() and sorted(list)?Convert every string to an integer: [['1', '2', '3'], ['4', '5', '6']]How to merge two sorted lists into one sorted list?How to check if all the elements in a given lists are unique? so [1, 2, 3] is unique but [1, 1, 2, 3] is not unique because 1 exists twiceYou have the following function
def my_func(li = []):
li.append("hmm")
print(li)
If we call it 3 times, what would be the result each call?
How to iterate over a list?How to iterate over a list with indexes?How to start list iteration from 2nd index?How to iterate over a list in reverse order?Sort a list of lists by the second item of each nested listCombine [1, 2, 3] and ['x', 'y', 'z'] so the result is [(1, 'x'), (2, 'y'), (3, 'z')]What is List Comprehension? Is it better than a typical loop? Why? Can you demonstrate how to use it?You have the following list: [{'name': 'Mario', 'food': ['mushrooms', 'goombas']}, {'name': 'Luigi', 'food': ['mushrooms', 'turtles']}] Extract all type of foods. Final output should be: {'mushrooms', 'goombas', 'turtles'}
Python Dictionaries
How to create a dictionary?How to remove a key from a dictionary?How to sort a dictionary by values?How to sort a dictionary by keys?How to merge two dictionaries?Convert the string "a.b.c" to the dictionary {'a': {'b': {'c': 1}}}
Common Algorithms Implementation
Can you implement "binary search" in Python?
Python Files
How to write to a file?How to print the 12th line of a file?How to reverse a file?Sum all the integers in a given filePrint a random line of a given filePrint every 3rd line of a given filePrint the number of lines in a given filePrint the number of of words in a given fileCan you write a function which will print all the file in a given directory? including sub-directoriesWrite a dictionary (variable) to a file
Python OS
How to print current working directory?Given the path /dir1/dir2/file1 print the file name (file1)Given the path /dir1/dir2/file1
Print the path without the file name (/dir1/dir2)
Print the name of the directory where the file resides (dir2)
How do you execute shell commands using Python?How do you join path components? for example /home and luig will result in /home/luigiHow do you remove non-empty directory?
Python Regex
How do you perform regular expressions related operations in Python? (match patterns, substitute strings, etc.)How to substitute the string "green" with "blue"?How to find all the IP addresses in a variable? How to find them in a file?
Python Strings
Find the first repeated character in a stringHow to extract the unique characters from a string? for example given the input "itssssssameeeemarioooooo" the output will be "mrtisaoe"Find all the permutations of a given stringHow to check if a string contains a sub string?Find the frequency of each character in stringCount the number of spaces in a stringGiven a string, find the N most repeated wordsGiven the string (which represents a matrix) "1 2 3\n4 5 6\n7 8 9" create rows and colums variables (should contain integers, not strings)What is the result of each of the following?
How to reverse a string? (e.g. pizza -> azzip)Reverse each word in a string (while keeping the order)What is the output of the following code: "".join(["a", "h", "m", "a", "h", "a", "n", "q", "r", "l", "o", "i", "f", "o", "o"])[2::3]
Python Iterators
What is an iterator?
Python Misc
Explain data serialization and how do you perform it with PythonHow do you handle argument parsing in Python?What is a generator? Why using generators?What would be the output of the following block?
for i in range(3, 3):
print(i)
What is yeild? When would you use it?Explain the following types of methods and how to use them:
Static method
Class method
instance method
How to reverse a list?How to combine list of strings into one string with spaces between the stringsYou have the following list of nested lists: [['Mario', 90], ['Geralt', 82], ['Gordon', 88]] How to sort the list by the numbers in the nested lists?Explain the following:
zip()
map()
filter()
Python - Slicing
For the following slicing exercises, assume you have the following list: my_list = [8, 2, 1, 10, 5, 4, 3, 9]
What is the result of `my_list[0:4]`?What is the result of `my_list[5:6]`?What is the result of `my_list[5:5]`?What is the result of `my_list[::-1]`?What is the result of `my_list[::3]`?What is the result of `my_list[2:]`?What is the result of `my_list[:3]`?
Python Debugging
How do you debug Python code?How to check how much time it took to execute a certain script or block of code?What empty return returns?How to improve the following block of code?
li = []
for i in range(1, 10):
li.append(i)
Given the following function
def is_int(num):
if isinstance(num, int):
print('Yes')
else:
print('No')
What would be the result of is_int(2) and is_int(False)?
Python - Linked List
Can you implement a linked list in Python?Add a method to the Linked List class to traverse (print every node's data) the linked listWrite a method to that will return a boolean based on whether there is a loop in a linked list or not
Python - Stack
Implement Stack in Python
Python Testing
What is your experience with writing tests in Python?What is PEP8? Give an example of 3 style guidelinesHow to test if an exception was raised?What assert does in Python?Explain mocksHow do you measure execution time of small code snippets?Why one shouldn't use assert in non-test/production code?
Flask
Can you describe what is Django/Flask and how you have used it? Why Flask and not Djano? (or vice versa)What is a route?What is a blueprint in Flask?What is a template?
zip
Given x = [1, 2, 3], what is the result of list(zip(x))?What is the result of each of the following:
Explain DescriptorsWhat would be the result of running a.num2 assuming the following code
class B:
def __get__(self, obj, objtype=None):
reuturn 10
class A:
num1 = 2
num2 = Five()
What would be the result of running some_car = Car("Red", 4) assuming the following code
class Print:
def __get__(self, obj, objtype=None):
value = obj._color
print("Color was set to {}".format(valie))
return value
def __set__(self, obj, value):
print("The color of the car is {}".format(value))
obj._color = value
class Car:
color = Print()
def __ini__(self, color, age):
self.color = color
self.age = age
Python Misc
How can you spawn multiple processes with Python?Implement simple calculator for two numbersWhat data types are you familiar with that are not Python built-in types but still provided by modules which are part of the standard library?Explain what is a decoratorCan you show how to write and use decorators?Write a decorator that calculates the execution time of a functionWrite a script which will determine if a given host is accessible on a given portAre you familiar with Dataclasses? Can you explain what are they used for?You wrote a class to represent a car. How would you compare two cars instances if two cars are equal if they have the same model and color?Explain Context ManagerTell me everything you know about concurrency in PythonExplain the Buffer ProtocolDo you have experience with web scraping? Can you describe what have you used and for what?Can you implement Linux's tail command in Python? Bonus: implement head as wellYou have created a web page where a user can upload a document. But the function which reads the uploaded files, runs for a long time, based on the document size and user has to wait for the read operation to complete before he/she can continue using the web site. How can you overcome this?How yield works exactly?
Monitoring
Explain monitoring. What is it? What its goal?What is wrong with the old approach of watching for a specific value and trigger an email/phone alert while value is exceeded?What types of monitoring outputs are you familiar with and/or used in the past?What is the different between infrastructure monitoring and application monitoring? (methods, tools, ...)
Prometheus
What is Prometheus? What are some of Prometheus's main features?Describe Prometheus architecture and componentsCan you compare Prometheus to other solutions like InfluxDB for example?What is an Alert?Describe the following Prometheus components:
Prometheus server
Push Gateway
Alert Manager
What is an Instance? What is a Job?What core metrics types Prometheus supports?What is an exporter? What is it used for?Which Prometheus best practices are you familiar with?. Name at least threeHow to get total requests in a given period of time?What HA in Prometheus means?How do you join two metrics?How to write a query that returns the value of a label?How do you convert cpu_user_seconds to cpu usage in percentage?
How do you know if a certain directory is a git repository?How to check if a file is tracked and if not, then track it?What is the difference between git pull and git fetch?Explain the following: git directory, working directory and staging areaHow to resolve git merge conflicts?What is the difference between git reset and git revert?You would like to move forth commit to the top. How would you achieve that?In what situations are you using git rebase?What merge strategies are you familiar with?How can you see which changes have done before committing them?How do you revert a specific file to previous commit?How to squash last two commits?What is the .git directory? What can you find there?What are some Git anti-patterns? Things that you shouldn't doHow do you remove a remote branch?Are you familiar with gitattributes? When would you use it?How do you discard local file changes? (before commit)How do you discard local commits?True or False? To remove a file from git but not from the filesystem, one should use git rmExplain Git octopus merge
Go
What are some characteristics of the Go programming language?What is the difference between var x int = 2 and x := 2?True or False? In Go we can redeclare variables and once declared we must use it.What libraries of Go have you used?What is the problem with the following block of code? How to fix it?
func main() {
var x float32 = 13.5
var y int
y = x
}
The following block of code tries to convert the integer 101 to a string but instead we get "e". Why is that? How to fix it?
package main
import "fmt"
func main() {
var x int = 101
var y string
y = string(x)
fmt.Println(y)
}
What is wrong with the following code?:
package main
func main() {
var x = 2
var y = 3
const someConst = x + y
}
What will be the output of the following block of code?:
package main
import "fmt"
const (
x = iota
y = iota
)
const z = iota
func main() {
fmt.Printf("%v\n", x)
fmt.Printf("%v\n", y)
fmt.Printf("%v\n", z)
}
What _ is used for in Go?What will be the output of the following block of code?:
package main
import "fmt"
const (
_ = iota + 3
x
)
func main() {
fmt.Printf("%v\n", x)
}
What will be the output of the following block of code?:
package main
import (
"fmt"
"sync"
"time"
)
func main() {
var wg sync.WaitGroup
wg.Add(1)
go func() {
time.Sleep(time.Second * 2)
fmt.Println("1")
wg.Done()
}()
go func() {
fmt.Println("2")
}()
wg.Wait()
fmt.Println("3")
}
What will be the output of the following block of code?:
package main
import (
"fmt"
)
func mod1(a []int) {
for i := range a {
a[i] = 5
}
fmt.Println("1:", a)
}
func mod2(a []int) {
a = append(a, 125) // !
for i := range a {
a[i] = 5
}
fmt.Println("2:", a)
}
func main() {
sl := []int{1, 2, 3, 4}
mod1(s1)
fmt.Println("1:", s1)
s2 := []int{1, 2, 3, 4}
mod2(s2)
fmt.Println("2:", s2)
}
What will be the output of the following block of code?:
package main
import (
"container/heap"
"fmt"
)
// An IntHeap is a min-heap of ints.
type IntHeap []int
func (h IntHeap) Len() int { return len(h) }
func (h IntHeap) Less(i, j int) bool { return h[i] < h[j] }
func (h IntHeap) Swap(i, j int) { h[i], h[j] = h[j], h[i] }
func (h *IntHeap) Push(x interface{}) {
// Push and Pop use pointer receivers because they modify the slice's length,
// not just its contents.
*h = append(*h, x.(int))
}
func (h *IntHeap) Pop() interface{} {
old := *h
n := len(old)
x := old[n-1]
*h = old[0 : n-1]
return x
}
func main() {
h := &IntHeap{4, 8, 3, 6}
heap.Init(h)
heap.Push(h, 7)
fmt.Println((*h)[0])
}
Mongo
What are the advantages of MongoDB? Or in other words, why choosing MongoDB and not other implementation of NoSQL?What is the difference between SQL and NoSQL?In what scenarios would you prefer to use NoSQL/Mongo over SQL?What is a document? What is a collection?What is an aggregator?What is better? Embedded documents or referenced?Have you performed data retrieval optimizations in Mongo? If not, can you think about ways to optimize a slow data retrieval?
Queries
Explain this query: db.books.find({"name": /abc/})Explain this query: db.books.find().sort({x:1})What is the difference between find() and find_one()?How can you export data from Mongo DB?
OpenShift
What is OpenShift?How OpenShift is related to Kubernetes?True or False? OpenShift is a IaaS (infrastructure as a service) solutionWhat would be the best way to run and manage multiple OpenShift environments?
OpenShift Federation
What is OpenShift Federation?Explain the following in regards to Federation:
Multi Cluster
Federated Cluster
Host Cluster
Member Cluster
OpenShift Azure
What is "OpenShift on Azure" and "Azure Red Hat OpenShift"?
Storage
What is a storage device? What storage devices are there?Explain the following:
Block Storage
Object Storage
File Storage
What is Random Seek Time?
Scripts
What do you tend to include in every script you write?Today we have tools and technologies like Ansible. Why would someone still use scripting?
Scripts Fundamentals
Explain conditionals and how do you use themWhat is a loop? What types of loops are you familiar with?Demonstrate how to use loops
Writing Scripts
Note: write them in any language you prefer
Write a script which will list the differences between two directoriesWrite a script to determine whether a host is up or downWrite a script to remove all the empty files in a given directory (also nested directories)
SQL
What does SQL stand for?How is SQL Different from NoSQLWhat does it mean when a database is ACID compliant?When is it best to use SQL? NoSQL?What is a Cartesian Product?
SQL Specific Questions
For these questions, we will be using the Customers and Orders tables shown below:
Customers
Customer_ID
Customer_Name
Items_in_cart
Cash_spent_to_Date
100204
John Smith
0
20.00
100205
Jane Smith
3
40.00
100206
Bobby Frank
1
100.20
ORDERS
Customer_ID
Order_ID
Item
Price
Date_sold
100206
A123
Rubber Ducky
2.20
2019-09-18
100206
A123
Bubble Bath
8.00
2019-09-18
100206
Q987
80-Pack TP
90.00
2019-09-20
100205
Z001
Cat Food - Tuna Fish
10.00
2019-08-05
100205
Z001
Cat Food - Chicken
10.00
2019-08-05
100205
Z001
Cat Food - Beef
10.00
2019-08-05
100205
Z001
Cat Food - Kitty quesadilla
10.00
2019-08-05
100204
X202
Coffee
20.00
2019-04-29
How would I select all fields from this table?How many items are in John's cart?What is the sum of all the cash spent across all customers?How many people have items in their cart?How would you join the customer table to the order table?How would you show which customer ordered which items?Using a with statement, how would you show who ordered cat food, and the total amount of money spent?
Azure
Explain Azure's architectureExplain availability sets and availability zonesWhat is Azure Policy?What is the Azure Resource Manager? Can you describe the format for ARM templates?Explain Azure managed disks
Azure Network
What's an Azure region?What is the N-tier architecture?
Azure Storage
What storage options Azure supports?
Azure Security
What is the Azure Security Center? What are some of its features?What is Azure Active Directory?What is Azure Advanced Threat Protection?What components are part of Azure ATP?Where logs are stored in Azure Monitor?Explain Azure Site RecoveryExplain what the advisor doesExplain VNet peeringWhich protocols are available for configuring health probeExplain Azure ActiveWhat is a subscription? What types of subscriptions are there?Explain what is a blob storage service
GCP
Explain GCP's architectureWhat are the main components and services of GCP?What GCP management tools are you familiar with?Tell me what do you know about GCP networkingExplain Cloud FunctionsWhat is Cloud Datastore?What network tags are used for?What are flow logs? Where are they enabled?How do you list buckets?What Compute metadata key allows you to run code at startup?What the following commands does? `gcloud deployment-manager deployments create`What is Cloud Code?
Google Kubernetes Engine (GKE)
What is GKE
Anthos
What is AnthosList the technical components that make up AnthosWhat is the primary computing environment for Anthos to easily manage workload deployment?How does Anthos handle the control plane and node components for GKE?Which load balancing options are available?Can you deploy Anthos on AWS?List and explain the enterprise security capabilities provided by AnthosHow can workloads deployed on Anthos GKE on-prem clusters securely connect to Google Cloud services?What is Island Mode configuration with regards to networking in Anthos GKE deployed on-prem?Explain Anthos Config ManagementHow does Anthos Config Management help?What is Anthos Service Mesh?Describe the two main components of Anthos Service MeshWhat are the components of the managed control plane of Anthos Service Mesh?How does Anthos Service Mesh help?List possible use cases of traffic controls that can be implemented within Anthos Service MeshWhat is Cloud Run for Anthos?How does Cloud Run for Anthos simplify operations?List and explain three high-level out of the box autoscaling primitives offered by Cloud Run for Anthos that do not exist in K8s nativelyList some Cloud Run for Anthos use cases
OpenStack
What components/projects of OpenStack are you familiar with?Can you tell me what each of the following services/projects is responsible for?:
Nova
Neutron
Cinder
Glance
Keystone
Identify the service/project used for each of the following:
Copy or snapshot instances
GUI for viewing and modifying resources
Block Storage
Manage virtual instances
What is a tenant/project?Determine true or false:
OpenStack is free to use
The service responsible for networking is Glance
The purpose of tenant/project is to share resources between different projects and users of OpenStack
Describe in detail how you bring up an instance with a floating IPYou get a call from a customer saying: "I can ping my instance but can't connect (ssh) it". What might be the problem?What types of networks OpenStack supports?How do you debug OpenStack storage issues? (tools, logs, ...)How do you debug OpenStack compute issues? (tools, logs, ...)
OpenStack Deployment & TripleO
Have you deployed OpenStack in the past? If yes, can you describe how you did it?Are you familiar with TripleO? How is it different from Devstack or Packstack?
OpenStack Compute
Can you describe Nova in detail?What do you know about Nova architecture and components?
OpenStack Networking (Neutron)
Explain Neutron in detailExplain each of the following components:
neutron-dhcp-agent
neutron-l3-agent
neutron-metering-agent
neutron-*-agtent
neutron-server
Explain these network types:
Management Network
Guest Network
API Network
External Network
What is a provider network?What components and services exist for L2 and L3?What is the ML2 plug-in? Explain its architectureWhat is the L2 agent? How does it works and what is it responsible for?What is the L3 agent? How does it works and what is it responsible for?Explain what the Metadata agent is responsible forWhat networking entities Neutron supports?How do you debug OpenStack networking issues? (tools, logs, ...)
OpenStack - Glance
Explain Glance in detailDescribe Glance architecture
OpenStack - Swift
Explain Swift in detailCan users store by default an object of 100GB in size?Explain the following in regards to Swift:
Container
Account
Object
True or False? there can be two objects with the same name in the same container but not in two different containers
OpenStack - Cinder
Explain Cinder in detailDescribe Cinder's components
OpenStack - Keystone
Can you describe the following concepts in regards to Keystone?
Role
Tenant/Project
Service
Endpoint
Token
What are the properties of a service? In other words, how a service is identified?Explain the following: * PublicURL * InternalURL * AdminURLWhat is a service catalog?
OpenStack Advanced - Services
Describe each of the following services
Swift
Sahara
Ironic
Trove
Aodh
Ceilometer
Identify the service/project used for each of the following:
Database as a service which runs on OpenStack
Bare Metal Provisioning
Track and monitor usage
Alarms Service
Manage Hadoop Clusters
highly available, distributed, eventually consistent object/blob store
OpenStack Advanced - Keystone
Can you describe Keystone service in detail?Describe Keystone architectureDescribe the Keystone authentication process
OpenStack Advanced - Compute (Nova)
What each of the following does?:
nova-api
nova-compuate
nova-conductor
nova-cert
nova-consoleauth
nova-scheduler
What types of Nova proxies are you familiar with?
OpenStack Advanced - Networking (Neutron)
Explain BGP dynamic routingWhat is the role of network namespaces in OpenStack?
OpenStack Advanced - Horizon
Can you describe Horizon in detail?What can you tell about Horizon architecture?
Security
What is DevSecOps? What its core principals?What security techniques are you familiar with? (or what security techniques have you used in the past?)What the "Zero Trust" concept means? How Organizations deal with it?Explain Authentication and AuthorizationHow do you manage sensitive information (like passwords) in different tools and platforms?Explain what is Single Sign-OnExplain MFA (Multi-Factor Authentication)Explain RBAC (Role-based Access Control)
Security - Web
What is Nonce?
Security - SSH
What is SSH how does it work?What is the role of an SSH key?
Security Cryptography
Explain Symmetrical encryptionExplain Asymmetrical encryptionWhat is "Key Exchange" (or "key establishment") in cryptography?True or False? The symmetrical encryption is making use of public and private keys where the private key is used to decrypt the data encrypted with a public keyTrue or False? The private key can be mathematically computed from a public keyTrue or False? In the case of SSH, asymmetrical encryption is not used to the entire SSH sessionWhat is Hashing?How hashes are part of SSH?Explain the following:
Vulnerability
Exploits
Risk
Threat
Are you familiar with "OWASP top 10"?What is XSS?What is an SQL injection? How to manage it?What is Certification Authority?How do you identify and manage vulnerabilities?Explain "Privilege Restriction"How HTTPS is different from HTTP?What types of firewalls are there?What is DDoS attack? How do you deal with it?What is port scanning? When is it used?What is the difference between asynchronous and synchronous encryption?Explain Man-in-the-middle attackExplain CVE and CVSSWhat is ARP Poisoning?Describe how do you secure public repositoriesHow do cookies work?What is DNS Spoofing? How to prevent it?What can you tell me about Stuxnet?What can you tell me about the BootHole vulnerability?What can you tell me about Spectre?Explain OAuthExplain "Format String Vulnerability"Explain DMZExplain TLSWhat is CSRF? How to handle CSRF?Explain HTTP Header Injection vulnerabilityWhat security sources are you using to keep updated on latest news?What TCP and UDP vulnerabilities are you familiar with?Do using VLANs contribute to network security?What are some examples of security architecture requirements?What is air-gapped network (or air-gapped environment)? What its advantages and disadvantages?Explain what is Buffer Overflow
Containers
What security measures are you taking when dealing with containers?Explain what is Docker BenchExplain MAC flooding attackWhat is port flooding?What is "Diffie-Hellman key exchange" and how does it work?Explain "Forward Secrecy"What is Cache Poisoned Denial of Service?
Security - Threats
Explain "Advanced persistent threat (APT)"What is a "Backdoor" in information security?
Puppet
What is Puppet? How does it works?Explain Puppet architectureCan you compare Puppet to other configuration management tools? Why did you chose to use Puppet?Explain the following:
Module
Manifest
Node
Explain FacterWhat is MCollective?Do you have experience with writing modules? Which module have you created and for what?Explain what is Hiera
Elastic
What is the Elastic Stack?Explain what is ElasticsearchWhat is Logstash?Explain what beats areWhat is Kibana?Describe what happens from the moment an app logged some information until it's displayed to the user in a dashboard when the Elastic stack is used
Elasticsearch
What is a data node?What is a master node?What is an ingest node?What is Coordinating node?How data is stored in elasticsearch?What is an Index?Explain ShardsWhat is an Inverted Index?What is a Document?You check the health of your elasticsearch cluster and it's red. What does it mean? What can cause the status to be yellow instead of green?True or False? Elasticsearch indexes all data in every field and each indexed field has the same data structure for unified and quick query abilityWhat reserved fields a document has?Explain MappingWhat are the advantages of defining your own mapping? (or: when would you use your own mapping?)Explain ReplicasCan you explain Term Frequency & Document Frequency?You check "Current Phase" under "Index lifecycle management" and you see it's set to "hot". What does it mean?What this command does? curl -X PUT "localhost:9200/customer/_doc/1?pretty" -H 'Content-Type: application/json' -d'{ "name": "John Doe" }'What will happen if you run the previous command twice? What about running it 100 times?What is the Bulk API? What would you use it for?
Query DSL
Explain Elasticsearch query syntax (Booleans, Fields, Ranges)Explain what is Relevance ScoreExplain Query Context and Filter ContextDescribe how would an architecture of production environment with large amounts of data would be different from a small-scale environment
Logstash
What are Logstash plugins? What plugins types are there?What is grok?How grok works?What grok patterns are you familiar with?What is `_grokparsefailure?`How do you test or debug grok patterns?What are Logstash Codecs? What codecs are there?
Kibana
What can you find under "Discover" in Kibana?You see in Kibana, after clicking on Discover, "561 hits". What does it mean?What can you find under "Visualize"?What visualization types are supported/included in Kibana?What visualization type would you use for statistical outliersDescribe in detail how do you create a dashboard in Kibana
Filebeat
What is Filebeat?If one is using ELK, is it a must to also use filebeat? In what scenarios it's useful to use filebeat?What is a harvester?True or False? a single harvester harvest multiple files, according to the limits set in filebeat.ymlWhat are filebeat modules?
Elastic Stack
How do you secure an Elastic Stack?
DNS
What is DNS? What is it used for?How DNS works?Explain the resolution sequence of: www.site.comWhat types of DNS records are there?What is a A record?What is a AAAA record?What is a PTR record?What is a MX record?Is DNS using TCP or UDP?True or False? DNS can be used for load balancingWhich techniques a DNS can use for load balancing?What is DNS Record TTL? Why do we need it?What is a zone? What types of zones are there?
Distributed
Explain Distributed Computing (or Distributed System)What can cause a system to fail?Do you know what is "CAP theorem"? (aka as Brewer's theorem)What are the problems with the following design? How to improve it? What are the problems with the following design? How to improve it? What is "Shared-Nothing" architecture?Explain the Sidecar Pattern (Or sidecar proxy)
Misc
What is a server? What is a client?Define or Explain what is an APIWhat is Automation? How it's related or different from Orchestration?Tell me about interesting bugs you've found and also fixedWhat is a Debuggger and how it works?What is Metadata?You can use one of the following formats: JSON, YAML, XML. Which one would you use? Why?
YAML
What is YAML?True or False? Any valid JSON file is also a valid YAML fileWhat is the format of the following data?
How to write a multi-line string with YAML? What use cases is it good for?What is the difference between someMultiLineString: | to someMultiLineString: >?What are placeholders in YAML?How can you define multiple YAML components in one file?
Jira
Explain/Demonstrate the following types in Jira:
Epic
Story
Task
What is a project in Jira?
Kafka
What is Kafka?In Kafka, how to automatically balance brokers leadership of partitions in a cluster?
Enable auto leader election and reduce the imbalance percentage ratio
Manually rebalance by using kafkat
Configure group.initial.rebalance.delay.ms to 3000
All of the above
Cassandra
When running a cassandra cluster, how often do you need to run nodetool repair in order to keep the cluster consistent?
Within the columnFamily GC-grace Once a week
Less than the compacted partition minimum bytes
Depended on the compaction strategy
Customers and Service Providers
What is SLO (service-level objective)?What is SLA (service-level agreement)?
HTTP
What is HTTP?Describe HTTP request lifecycleTrue or False? HTTP is statefulHow HTTP request looks like?What HTTP method types are there?What HTTP response codes are there?What is HTTPS?Explain HTTP CookiesWhat is HTTP Pipelining?You get "504 Gateway Timeout" error from an HTTP server. What does it mean?What is a proxy?What is a reverse proxy?What is CDN?When you publish a project, you usually publish it with a license. What types of licenses are you familiar with and which one do you prefer to use?
Load Balancers
What is a load balancer?What benefits load balancers provide?What load balancer techniques/algorithms are you familiar with?What are the drawbacks of round robin algorithm in load balancing?What is an Application Load Balancer?In which scenarios would you use ALB?At what layers a load balancer can operate?Can you perform load balancing without using a dedicated load balancer instance?What is DNS load balancing? What its advantages? When would you use it?What are sticky sessions? What are their pros and cons?Explain each of the following load balancing techniques
Round Robin
Weighted Round Robin
Least Connection
Weighted Least Connection
Resource Based
Fixed Weighting
Weighted Response Time
Source IP Hash
URL Hash
Explain use case for connection draining?
Licenses
Are you familiar with "Creative Commons"? What do you know about it?Explain the differences between copyleft and permissive licenses
Random
How a search engine works?How auto completion works?What is faster than RAM?What is a memory leak?What is your favorite protocol?What is Cache API?What is the C10K problem? Is it relevant today?
HR
These are not DevOps related questions as you probably noticed, but since they are part of the DevOps interview process I've decided it might be good to keep them
Tell us little bit about yourselfTell me about your last big project/task you worked onWhat was most challenging part in the project you worked on?How did you hear about us?How would you describe a good leadership? What makes a good boss for you?Tell me about a time where you didn't agree on an implementationHow do you deal with a situation where key stakeholders are not around and a big decision needs to be made?Where do you see yourself 5 years down the line?Give an example of a time when you were able to change the view of a team about a particular tool/project/technologyHave you ever caused a service outage? (or broke a working project, tool, ...?)Rank the following in order 1 to 5, where 1 is most important: salaray, benefits, career, team/people, work life balanceYou have three important tasks scheduled for today. One is for your boss, second for a colleague who is also a friend, third is for a customer. All tasks are equally important. What do you do first?You have a colleague you don‘t get along with. Tell us some strategies how you create a good work relationship with them anyway.What do you love about your work?What are your responsibilities in your current position?Why should we hire you for the role?
Pointless Questions
Why do you want to work here?Why are you looking to leave your current place?What are your strengths and weaknesses?Where do you see yourself in five years?
Team Lead
How would you improve productivity in your team?
Questions you CAN ask
A list of questions you as a candidate can ask the interviewer during or after the interview. These are only a suggestion, use them carefully. Not every interviewer will be able to answer these (or happy to) which should be perhaps a red flag warning for your regarding working in such place but that's really up to you.
What do you like about working here?How does the company promote personal growth?What is the current level of technical debt you are dealing with?Why I should NOT join you? (or 'what you don't like about working here?')What was your favorite project you've worked on?If you could change one thing about your day to day, what would it be?Let's say that we agree and you hire me to this position, after X months, what do you expect that I have achieved?
Testing
Explain white-box testingExplain black-box testingWhat are unit tests?What types of tests would you run to test a web application?Explain test harness?What is A/B testing?What is network simulation and how do you perform it?What types of performances tests are you familiar with?Explain the following types of tests:
Load Testing
Stress Testing
Capacity Testing
Volume Testing
Endurance Testing
Databases
What is sharding?You find out your database became a bottleneck and users experience issues accessing data. How can you deal with such situation?What is a connection pool?What is a connection leak?What is Table Lock?Your database performs slowly than usual. More specifically, your queries are taking a lot of time. What would you do?What is a Data Warehouse?Explain what is a time-series databaseWhat is OLTP (Online transaction processing)?What is OLAP (Online Analytical Processing)?What is an index in a database?
Regex
Given a text file, perform the following exercises
Extract
Extract all the numbersExtract the first word of each lineExtract all the IP addressesExtract dates in the format of yyyy-mm-dd or yyyy-dd-mmExtract email addresses
Replace
Replace tabs with four spacesReplace 'red' with 'green'
System Design
Explain what is a "Single point of failure" and give an exampleExplain "3-Tier Architecture" (including pros and cons)What are the drawbacks of monolithic architecture?What are the advantages of microoservices architecture over a monolithic architecture?What's a service mesh?Explain "Loose Coupling"What is a message queue? When is it used?
Scalability
Explain ScalabilityExplain ElasticityExplain Fault Tolerance and High AvailabilityExplain Vertical ScalingWhat are the disadvantages of Vertical Scaling?Explain Horizontal ScalingWhat is the disadvange of Horizontal Scaling? What is often required in order to perform Horizontal Scaling?Explain when in which use cases will you use vertical scaling and in which use cases you will use horizontal scalingExplain Resiliency and what ways are there to make a system more resilientExplain "Consistent Hashing"How would you update each of the services in the following drawing without having app (foo.com) downtime? What is the problem with the following architecture and how would you fix it? Users report that there is huge spike in process time when adding little bit more data to process as an input. What might be the problem? How would you scale the architecture from the previous question to hundreds of users?
Cache
What is "cache"? In which cases would you use it?What is "distributed cache"?What is a "cache replacement policy"?Which cache replacement policies are you familiar with?Explain the following cache policies:
FIFO
LIFO
LRU
Why not writing everything to cache instead of a database/datastore?
Migrations
How you prepare for a migration? (or plan a migration)Explain "Branch by Abstraction" technique
Design a system
Can you design a video streaming website?Can you design a photo upload website?How would you build a URL shortener?
What is a CPU?What is RAM?What is an embedded system?Can you give an example of an embedded system?What types of storage are there?
Big Data
Explain what is exactly Big DataWhat is DataOps? How is it related to DevOps?What is Data Architecture?Explain the different formats of dataWhat is a Data Warehouse?What is Data Lake?Can you explain the difference between a data lake and a data warehouse?What is "Data Versioning"? What models of "Data Versioning" are there?What is ETL?
Apache Hadoop
Explain what is HadoopExplain Hadoop YARNExplain Hadoop MapReduceExplain Hadoop Distributed File Systems (HDFS)What do you know about HDFS architecture?
Ceph
Explain what is CephTrue or False? Ceph favor consistency and correctness over performancesWhich services or types of storage Ceph supports?What is RADOS?Describe RADOS software componentsWhat is the workflow of retrieving data from Ceph?What is the workflow of retrieving data from Ceph?What are "Placement Groups"?Describe in the detail the following: Objects -> Pool -> Placement Groups -> OSDsWhat is OMAP?What is a metadata server? How it works?
Packer
What is Packer? What is it used for?Packer follows a "configuration->deployment" model or "deployment->configuration"?
Certificates
If you are looking for a way to prepare for a certain exam this is the section for you. Here you'll find a list of certificates, each references to a separate file with focused questions that will help you to prepare to the exam. Good luck :)
