diff --git a/README.md b/README.md index e4ced27..67c9cdb 100644 --- a/README.md +++ b/README.md @@ -2,7 +2,7 @@ :information_source:  This repo contains questions and exercises on various technical topics, sometimes related to DevOps and SRE :) -:bar_chart:  There are currently **999** questions +:bar_chart:  There are currently **1013** questions :warning:  You can use these for preparing for an interview but most of the questions and exercises don't represent an actual interview. Please read [Q&A](common-qa.md) for more details @@ -1375,6 +1375,16 @@ Hardware -> Kernel -> Daemons, System Libraries, Server Display. ##### Debugging (Beginner) +
+Where system logs are located?
+
+ +
+How to follow file's content as it being appended without opening the file every time?
+ +tail -f +
+
What are you using for troubleshooting and debugging network issues?
@@ -1515,6 +1525,17 @@ Hardware -> Kernel -> Daemons, System Libraries, Server Display. 3. Lines which end with a number
+
+Which line numbers will be printed when running `grep '\baaa\b'` on the following content: + +aaa +bbb +ccc.aaa +aaaaaa
+ +lines 1 and 3. +
+
What is the difference single and double quotes?
@@ -1541,7 +1562,7 @@ Each number has different meaning, based on how the application was developed. I consider this as a good blog post to read more about it: https://shapeshed.com/unix-exit-codes -##### Storage & Filesystem (Beginner) +##### Linux - Storage & Filesystem
What's an inode?
@@ -2017,6 +2038,10 @@ Upstart: add Upstart init script at /etc/init/service.conf How do you create users? Where user information is stored?
+
+Which file stores information about groups?
+
+
How do you change/set the password of a user?
@@ -2059,6 +2084,26 @@ Re-install the OS IS NOT the right answer :) Using the last command.
+#### Linux - Hardware + +
+Where can you find information on the processor?
+ +/proc/cpuinfo +
+ +
+How can you print information on the BIOS, motherboard, processor and RAM?
+ +dmidecoode +
+ +
+How can you print all the information on connected block devices in your system?
+ +lsblk +
+ #### Linux - Random
@@ -3240,6 +3285,59 @@ Setting the replicas to 0 will shut down the process. Now start it with `kubectl Describe how roll-back works
+
+What is the control loop? How it works?
+ +Explained [here](https://www.youtube.com/watch?v=i9V4oCa5f9I) +
+ +#### Kubernetes Operators + +
+What is an Operator?
+ +Explained [here](https://coreos.com/operators) + +"An Operator is a method of packaging, deploying and managing a Kubernetes application" +
+ +
+What components the Operator consists of?
+ +1. CRD (custom resource definition) +2. Controller - Custom control loop which runs against the CRD +
+ +
+What is the Operator Framework?
+ +open source toolkit used to manage k8s native applications, called operators, in an automated and efficient way. +
+ +
+What components the Operator Framework consists of??
+ +1. Operator SDK - allows developers to build operators +2. Operator Lifecycle Manager - helps to install, update and generally manage the lifecycle of all operators +3. Operator Metering - Enables usage reporting for operators that provide specialized services +
+ + +
+Describe in detail what is the Operator Lifecycle Manager
+ +It's part of the Operator Framework, used for managing the lifecycle of operators. It basically extends Kubernetes so a user can use a declarative way to manage operators (installation, upgrade, ...). +
+ +
+What openshift-operator-lifecycle-manager namespace includes?
+ +It includes: + + * catalog-operator - Resolving and installing ClusterServiceVersions the resource they specify. + * olm-operator - Deploys applications defined by ClusterServiceVersion resource +
+ #### Kubernetes Commands
@@ -5369,7 +5467,7 @@ as key-value pair, document-oriented, etc. #### :baby: Beginner
-What is OpenShift? Did you use it? If yes, how?
+What is OpenShift? What experience do you have with OpenShift?
@@ -6021,7 +6119,7 @@ startap-script * neutron-dhcp-agent - DHCP services * neutron-metering-agent - L3 traffic metering * neutron-*-agtent - manages local vSwitch configuration on each compute (based on chosen plugin) - * neutron-server - exposes networking API and passes requests to other plugins if required
+ * neutron-server - exposes networking API and passes requests to other plugins if required
@@ -6096,7 +6194,7 @@ Using:
-What is a service catalog? +What is a service catalog?
A list of services and their endpoints