Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

AWS Solutions Architect -- Associate > Section 9: RDS. Aurora & ElastiCache > Flashcards

Section 9: RDS. Aurora & ElastiCache Flashcards

1
Q

What is Amazon RDS (relational Database Service)?

A

Amazon RDS is a collection of managed services that make it simple to set up, operate and scale relational databases in the cloud

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the eight (8) advantages of using RDS versus deploying a DB on EC2?

A

1) Autoamted Provisioning and OS patching
2) Continuous backups and point-in-time restore
3) Monitoring dashboards
4) Read replicas for improved read performance
5) Multi AZ setup for disaster recovery
6) Maintenance windows for upgrades
7) Horizontal and Vertical scaling capability
8) Storage backed by EBS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the retention period for RDS Backups, and how are the backups stored?

A

The retention period is 1 to 35 days, and the backups are stored in S3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How do RDS Read Replicas work?

A

Data is written from an application to an RDS DB instance. A snapshot of the DB is created to replicate it, and the data is then copied to replicas with asynchronous replication. Async replication ensures reads are consistent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Can RDS read replicas have replicas themselves?

A

Yes, however it is important to be aware of latency in these scenarios.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How many replicas can you have of a given RDS DB?

A

Up to five (5) read replicas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Are RDS read replicas meant for disaster recovery?

A

No. Although they can be used for disaster recovery in certain cases, RDS read replicas are meant for scaling, not disaster recovery.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is RDS Multi-AZ?

A

A snapshot is taken to make a DB copy. A new DB is then restored from a snapshot in a new AZ. Synchronization is then establish between the DBs, and this does hot have a major effect on performance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Is RDS Multi-AZ meant for disaster recovery?

A

Yes, RDS Multi-AZ is meant for disaster recovery and not improving performance. However it is confined to the DB AZ. If disaster recovery across regions is required, Aurora Global Database should be used.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is Amazon Aurora?

A

Amazon Aurora is a MySQL and PostgreSQL compatible relational database engine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why is Aurora Better than RDS?

A

1) higher performance and availability
2) More expensive, but more efficient
3) Has instantaneous failover
4) Storage grows automatically in increments of 10 GB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is an Aurora DB Cluster?

A

Aurora DB clusters consist of one or more DB instances and a cluster volume that manages the data for those DB instances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do Aurora DB Clusters work?

A

1) The main DB is the only DB that can write to the shared volume
2) Load balancing is used to connect read replicas to one reader endpoint
3) the reader endpoint connects to the client, and the client is connected separately to the write endpoint which is connected to the master DB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do Aurora security and RDS security differ?

A

They do not differ.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is Aurora Serverless and what are its benefits?

A

Aurora Serverless is Aurora with on-demand, autoscaling configuration, automatic startup / shut down and automatic scaling based on application needs.
The main benefit is its cost-effectiveness for infrequent / unpredictable workloads.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is Amazon ElastiCache

A

ElastiCache is a service that allows you to deploy, operate, and scale in-memory caches in the cloud.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are four (4) main use cases of ElastiCache?

A

1) Storing user session data
2) Scaling DB reads with only the most current data
3) Make your application stateless
4) Increases web app and DB performance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the two ElastiCache caching engines?

A

1) Redis
2) Memcached

19
Q

What are the four (4) key qualities of Memcached?

A

1) simple and easy to get started
2) Not highly available
3) Non-persistent
4) No backup and no restore

20
Q

What are the main qualities of Redis?

A

1) Native encryption service
2) Auto-failover
3) Read replicas for scaling and high availability
4) backup and restore features
5) More advanced features and more difficult than Memcached

21
Q

What is the Lazy Loading pattern for ElastiCache?

A

Lazy Loading is when all the read data is cached, but data can become scale in the cach

22
Q

What is the Write Through pattern for ElastiCache?

A

The write-through pattern adds or updates data in the cache when writing to a DB (meaning no stale data)

23
Q

What is the Session Store pattern fir ElastiCache?

A

Session Store stores temporary session data in a cache

24
Q

What is DNS?

A

DNS is the Domain Name System, which translates human friendly hostnames into machine IP addresses.

25
Q

Which part of a domain name is the “top level” domain? The Second level?

A

The “top level” domain is the last word in a domain name (.com, .net).
The “second level” = amazon.com, google.com etc.

26
Q

What is a Domain Registrar?

A

An authority that can assign domain names (like GoDaddy, Amazon)

27
Q

What are the four (4) DNS records?

A

1) A
2) AAAA
3) CNAME
4) NS

28
Q

What is Amazon Route 53?

A

Route 53 is Amazons own internal DNS and Domain Registrar. It is highly available, scalable, fully managed and authoritative DNS (authoritative = the customer can update the DNS records)

29
Q

What are 2 details about Route 53?

A

Route 53 is the only AWS servce with 100% availability, and gives customers the ability to check the health of their resources.

30
Q

What is a Route 53 Record?

A

A route 53 Record records how you want to route traffic for a domain.

31
Q

What does each Route 53 Record Contain?

A

1) Domain / subdomain name
2) the record type (A, AAAA etc.)
3) A value (example: 12.34.56.78)
4) A Routing Policy (how Route 53 should respond to queries)
5) TTL (amount of time the record is cached at DNS Resolvers)

32
Q

What is TTL?

A

TTL, or Time to Live, is the length that a DNS record is cached on the resolving server or a user’s local machine. The lower the TTL, the quicker changes to DNS records propagate through the internet.

33
Q

TTL is mandatory for all DNS records except which type?

A

TTL is mandatory for all DNS records except Alias Records

34
Q

What is a high TTL? Low TTL?

A

A high TTL is 24 hours, for less traffic on Route 53 but possibly outdated records.
A low TTL is 60 seconds, for when there is more traffic on Route 53. As a result of a low TTL, records are quicker, easier to change and more up to date. However low TTL is expensive $$

35
Q

What is a Hosted Zone?

A

A Hosted Zone is a record that define how to reroute traffic to a domain and subdomain.

36
Q

What is a Public Hosted Zone?

A

A Public HZ contains records that specify how to reroute traffic on the internet, to public domain names

37
Q

What is a Private Hosted Zone?

A

A Private HZ contains records that specify how to route traffic within one or more private domain names (VPCs)

38
Q

What is a NS and what does it do?

A

NS = Name Servers for Hosted Zones. NS’s specify which DNS server is authoritative for that domain (as in, which server has the actual DNS records).

39
Q

Who / what uses Name Servers?

A

Name Servers are used by top level domain servers to direct traffic to the authoritative name server, even though a domain may have multiple NS records to indicate a primary and backup server.

40
Q

The A Record Type maps a domain name to ___

A

IPv4

41
Q

The AAAA record type maps a domain name to ____

A

IPv6

42
Q

CNAME record type maps a domain name to ____

A

Another host name with the target domain name being an A or AAAA record. Only works for non root domain (example: no CNAME for nut.com, but possible for www.nut.com)

43
Q

Alias record type maps a HOSTNAME to ____

A

An AWS resource. Free of charge and triggers native health checks. Alias records are always type A / AAAA for AWS resources.

44
Q

What do Route 53 Routing Policies do?

A

Routing Policies define how Route 53 responds to DNS queries.

AWS Solutions Architect -- Associate (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions