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What to Expect and Tips

• 45-minute systems interview, focus on responding to real world problems with an unhealthy service, such as a web server or database. The interview will start off at a high level troubleshooting a likely scenario, dig deeper to find the cause and some possible solutions for it. The goal is to probe your knowledge of systems at scale and under load, so keep in mind the challenges of the Facebook environment.
• Focus on things such as tooling, memory management and unix process lifecycle.

Systems

More specifically, linux troubleshooting and debugging. Understanding things like memory, io, cpu, shell, memory etc. would be pretty helpful. Knowing how to actually write a unix shell would also be a good idea. What tools might you use to debug something? On another note, this interview will likely push your boundaries of what you know (and how to implement it).

Design/Architecture 

Interview is all about taking an ambiguous question of how you might build a system and letting

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{
    "Volumes": [
        {
            "AvailabilityZone": "us-west-2a",
            "Attachments": [
                {
                    "AttachTime": "2013-09-17T00:55:03.000Z",
                    "InstanceId": "i-a071c394",
                    "VolumeId": "vol-e11a5288",
                    "State": "attached",

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{
    "DBInstances": [
        {
            "PubliclyAccessible": false,
            "MasterUsername": "mymasteruser",
            "MonitoringInterval": 0,
            "LicenseModel": "general-public-license",
            "VpcSecurityGroups": [
                {
                    "Status": "active",

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#!/usr/bin/env python
"""
mocking requests calls

"""
import mock
import unittest
import requests
from requests.exceptions import HTTPError

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// 🔥 Node 7.6 has async/await! Here is a quick run down on how async/await works

const axios = require('axios'); // promised based requests - like fetch()

function getCoffee() {
  return new Promise(resolve => {
    setTimeout(() => resolve('☕'), 2000); // it takes 2 seconds to make coffee
  });
}

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# PROBLEM LINK : https://www.hackerrank.com/challenges/temperature-predictions

import numpy as np
from sklearn import ensemble

def isfloat(value):
  try:
    float(value)
    return True

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cd %systemroot%\system32\drivers
sc query cldflt
sc config cldflt start=auto

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import boto3
import json
import sys


encodedMessageStr = sys.argv[1]
client = boto3.client('sts')
response = client.decode_authorization_message(
    EncodedMessage=encodedMessageStr
)

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Summary

1. Change file /etc/sysconfig/network
2. Change file /etc/hostname
3. Chnage file /etc/hosts

sudo vim /etc/sysconfig/network

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Description: Create WebACL example
Parameters:
  WebACLDefaultAction:
    Type: String
    AllowedValues:
      - Allow
      - Block
  
  WebACLRuleAction:
    Type: String