PSRE – Pretest (nayakar)
Q1 – What are the differences between SRE and DevOps?
Ans. SRE and DevOps are closely related fields. SRE perspective is understanding and managing service availability and monitoring them by making use of tools or automation. Devops is focused more on release management and service automation tasks along through tools or scripts. SREs focus is on client SLA/SLOs, DevOps need not consider client SLA/SLOs.
Q2 – What SRE team is responsible for?
Ans. SRE team is responsible for application availability, make sure SLAs are met for client, monitoring stack for organization and tools and automation to achieve these aspects.
Q3 – What is an error budget?
Ans. An error budget is getting details of error rates for any particular application and calculating if it meets client expectations or if we breaching SLA.
Q4 – What are MTTF (mean time to failure) and MTTR (mean time to repair)? What these metrics help us to evaluate?
Ans. These metrics help us in evaluating and understanding incident metrics. Not quite sure of their specifications.
Q5 – What is the role of monitoring in SRE?
Ans. To monitor host resources like CPU,memory,disk and also application url monitoring along with slowness using APMs and opensource monitoring tools.
Q6 – How do you differentiate between process and thread?
Ans. Threads are child processes of a process. The PPID of a thread has process PID.
Q7 – What activity means Reducing Toil?
Ans. I don’t know
Q8 – Have you ever heard of SLO? If yes then explain.
Ans. SLOs are Service level objectives, these are objectives defined within application which help in meeting client SLAs.
Q9 – Enlist all the Linux signals you are aware of
Ans. kill and terminate
Q10 – What is obserbability
Ans. Observability is ability to get a complete view and understanding of systems available in an application stack and able to monitor and identify any failures.