## Interview Qs:

What is the main difference between Ubuntu/Debian and Centos/RHEL ?

If you needed to add software repositories to ubuntu or centos, how would you do it ? How does GPG/PGP figure into this ?

What happens when you browse to www.google.com - describe the behaviours that take place in udp and tcp. ?

Please give an example of a naming schema that makes sense (give or offer context) ?

You're building out a new infrastrcuture for a stack in $cloud and it will be networked with the private corporate network, what information do you need ?

How many IPs are there in a /24 subnet ?

How many /25 subnets are in a /23 subnet ?

Is 172.70.0.0/16 part of RFC1918 (aka, is it a private subnet?) ? - you can go read the RFC if you want and then explain it

What is the main 'new feature' difference between HTTP 1.0 and 1.1 ?

What is the difference between a subnet and a vlan, as it relates to cloud networking ?

How are devices typically presented in Linux/Unix ?

What is a pipe in unix and how is it used ? Examples please.

What is the difference and significance between `HTTP_PROXY=http://localhost:8080 curl http://www.google.com` and `curl --proxy http://localhost:8080 http://www.google.com` ?

Please explain how you layout a Terraform repo ? What is the difference between 'resource' and 'data' in terraform ?

What is a go/terraform provider ?

Let's go review an opensource pull request - you may suggest your own, or we can go to https://github.com/terraform-aws-modules/terraform-aws-vpc/pulls and pick one from there. Discuss the changes.

Have you used rsync ? In what circumstances ? Describe its behaviour ?

What would be cool if you mixed up rsync and ZFS/BTRFS snapshotting ?

What is the difference between a git branch and a git tag ?

What is the default transport of rsync between hosts ?

How does SSH Public Key Authentication work ? What is so good about this vs passwords ?

K8S - what happens if you delete a pod ?

K8S - have you ever seen 'imagepullbackoff' - what does it really mean ?

You have an active-active redundant cluster of machines - and they are running out of disk space. How would you increase space without causing an outage ?

mkdir a ; cd a ; touch b ; ls > c ; cat c what is going to be inside c - what bash will do, how does it work.

You are manually working on a mysql database. You need to insert "Mark O'Hanon" (including apostrophe) into the 'name' column of the 'users' table - how do you do it ?

You've just made a manual change, based on a slack message. It works now! What do you do next ?

## Open-Ended questions that need to be done "live"

Scripting Question - https://www.metoffice.gov.uk/pub/data/weather/uk/climate/stationdata/heathrowdata.txt -  work out which month, of which year, had the greatest temperature range. Script it. Any language you like !
(Pseudocode is permitted..)

Operational outage scenario - automated alert indicates an important site is down - you can't seem to fix it, what do you do ? (interviewer needs to make things up as you go) (point is to time how long they take to escalate.)

What are the benefits of automation - Can you give some examples you have of your own automation work ? Talk me through it.

## Interviewee Questions:

# Have you got any questions for me ? ( The more they ask the better as long as they are company/role/tech related).