DocumentDB

Question 1

Overview of DOcDB

• fully managed (non-rlational)document DB for MOngoDB workloads
• JSON documents(nested key value pairs) stored in collections (~tables)
• compatible with majority of mongoDB apps, drives, and tools
• high eprformance, scalability, and availability
• support for flexible indexing, powerful ad hoc queries and aanlytics
• storage and compute can scale independently
• supports 15 low latency read replicas (multi-az)
• auto scaling of storage from 10GB to 64TB
• FAULT TOLERANT AND SELF HEALING STORAGE

AUTOMATIC, CONTINUOUS, incremental backups and PITR

Answer 1

T

Question 2

docdb stores JSON documents (semi structured data)

Answer 2

T

Question 3

key vaue pairs can be nested

Answer 3

T

Question 4

why docdb?

• JSON is the defacto format for data exchange
• documentDB makes it easy to insert, query, index, and perform aggregations over JSON data
• store JSON output from APIs straight into DB and start analyzing it
• flexible document model, data types, and indexing
• add/remove indexes easily

run ad hoc queries for operational and analytics workloads

for known access patterns - use dynamoDB instead

Answer 4

T

Question 5

DocDB architecture

___ copies of your data across ___ AZs

Answer 5

6, 3

Question 6

DocDB Architecture

_____ optimistic algorithm (quorum model)

Answer 6

lock-free

Question 7

docdb architecture

___ copies out of 6 needed for writes (__/6 write quorum - data considered durable whe at least __/6 copies acknowledge the write)

Answer 7

4

Question 8

docdb architecture

___ copies out of 6 needed for reads (__/6 read quorum

Answer 8

3

Question 9

docdb architecture

self healing with ____ replication, storage is striped across 100s of volumes

Answer 9

peer to peer

Question 10

docdb architecture

___ docdb isntance takes writes(master)

Answer 10

1

Question 11

___ nodes on replicas do not need to write/replicate (=improved read performance)

Answer 11

compute

Question 12

docdb architecture

log-structured distributed storage layer - passes ___ log records from compute to stroage layer (=faster)

Answer 12

incremental

Question 13

docdb architecture

master + up to ___ read replicas server reads

Answer 13

15

Question 14

docdb architecture

data is continuously backed up to __ in real time, using storage nodes (compute nore perfomance is unaffected)

Answer 14

s3

Question 15

docdb cluster

• recommended to connect using the cluster endpoint in replica set mode (enables your SDK to auto discover the cluster arrangement as instances get added or removed from the cluster)

Answer 15

T

Question 16

docdb replication

• up to ___ read replicas

Answer 16

15

Question 17

docdb replication

____ repliaction

Answer 17

ASYNC

Question 18

docdb replication

replicas share the same underlying storage layer

Answer 18

T

Question 19

docdb replication

typically take 10s of milliseconds (replication lag)

Answer 19

T

Question 20

docdb replication

minimal performance impact on the primary due to replication process

Answer 20

T

Question 21

docdb HA failovers

-failovers occur automatically

Answer 21

T

Question 22

docdb HA failovers

-a replica is automatically promoted to be the new primary during DR

Answer 22

T

Question 23

docdb HA failovers

docdb flops the CNAME of the DB instance to point ot the replica and promotes it

Answer 23

T

Question 24

docdb HA failovers

failover to a replica typically takes 30 seconds ( minimal downtime)

Answer 24

t

Question 25

docdb HA failovers creating a new instance takes about 8-10 minutes (post failover)

Answer 25

t

Question 26

docdb backup and restore - supports automatic backups

Answer 26

`T

Question 27

docdb backupa dn restore continuously backs up your data to s3 for PITR (max retention period of \_\_days)

Answer 27

35

Question 28

docdb backup and restore latest restorable time for a PITR can be up to 5 minutes in the past

Answer 28

T

Question 29

docdb backup and restore - the first backup is a full backup - subsequent backups are \_\_\_\_

Answer 29

incremental

Question 30

docdb backup and restore take manual snapshots to retain beyond 35 days

Answer 30

T

Question 31

docdb backup and restore backup process dfoesnot impact cluster performance

Answer 31

t

Question 32

docdb backup and restore - can only restore to a new cluster

Answer 32

T

Question 33

docdb backup and restore can restore an unencrypted snapshot to an encrypted cluster (but not hte other way round)

Answer 33

T

Question 34

docdb backup and restore to restore a cluster from an encrypted snapshot, you must have access to the KMS key

Answer 34

T

Question 35

docdb backup and restore can only share manual snapshots (can copy and share auto ones)

Answer 35

T

Question 36

docdb backup and restore can't share a snaptho encrypted using the defaut KMS keys of teh a/c

Answer 36

T

Question 37

docdb backup and restore shapshots can be shared across accounts, but within the same region

Answer 37

T

Question 38

docdb scaling - mongoDB sharding not supported (instead offers read replicas/vertical scaling/storage scaling) - vertical scaling (scale up/down - by resizing instances - horizontal scaling (scale out/in) by adding /removing up to 15 replicas - can scale up a replica independently from other replicas (typically for analytical workloads

Answer 38

T

Question 39

docdb security - IAM and Network - you use IAM to manage docdb resources

Answer 39

T

Question 40

docdb security - IAM and Network supports mongodb default auth ____ for db authentication

Answer 40

SCRAM(Salted Challenge Respose Authentication Mechanism)

Question 41

docdb security - IAM and Network supports built in roles for DB users with \_\_\_\_

Answer 41

RBAC(role based access control)

Question 42

docdb security - IAM and Network docdb clusters are VPC only (use private subnets)

Answer 42

T

Question 43

docdb security - IAM and Network clients (mongodb shell) can run on ec2 in public subnets wihtin VPC

Answer 43

T

Question 44

docdb security - IAM and Network can connect to your on prem IT infra via VPN

Answer 44

T

Question 45

Docdb security - encryption encryption at rest - AES-256 using KMS -applied to cluster data/replicas/indexes/logs/backups/snapshots encryption in transit - using TLS -to enable TLS, set tls parameter in cluster param group to conenct over TLS: download the cert (public key) from AWS -pass the cert key while connecting to the cluter

Answer 45

T

Question 46

docdb pricing - on demand instances - pricing per second with a 10 min minimum - IOPS - per million IO requests - each DB page reads operation from teh storage volume counts as one IO (one page = 8KB) - write IOs are counted in 4KB units DB storage - per GB per month backups - per GB per month(backups up to 100% of your clusters data storage is free) data tarnsfer - per GB can temporarily stop compute instances for up to 7 days

Answer 46

T

Question 47

docdb monitoring API calls logged with \_\_\_\_

Answer 47

cloudtrail

Question 48

docdb monitoring common CW metrics - CPU or RAM utilization - CPUUtilization/FreeableMemory - IOPS metrics - VolumeReadIOPS/VulumeWriteIOPS/WriteIOPS/ReadIOPS - Databaes conenctions - DatabaseConnections - Network Traffic - NetworkThroughput - Storage volume consumption - VolumeBytesUsed

Answer 48

T

Question 49

docdb monitoring -two types of logs can be published/exported to CW logs profiler logs audit logs

Answer 49

T

Question 50

docdb profiler - logs (into CW logs) the details of ops performed on your cluster - helps identify slow operations and improve quey performance - accesible from CW logs - to anable: - set parameters, profiler, profiler\_threshold\_ms, and profiler\_sampling\_rate - enable logs exports for audit logs by modifying the intance - both the steps above are mandatory

Answer 50

T

Question 51

docdb audit logs - records DDL statements, authentication, authorization, and user mgmt events to CW logs - exports your cluster's auditing records (JSON docs) to CW logs - accessible from CW logs to enable: - set parameter audit\_logs=enabled - enable logs exports for audit logs by modifying the instance

Answer 51

T

Question 52

docdb performance management - use explain command to identify slow queries db. runComamnd({explain: {}}) - can use db.adminCommand to find and terminate queries example: to terminate long running /blocked queries db. adminCommand({killOp: 1, op: });

Answer 52

t