Ch2 Flashcards
- Which of the following databases support read replicas?
MariaDB
MySQL
PostgreSQL
All of the above
D. MariaDB, MySQL, PostgreSQL supports READ replica. Oracle, Aurora dont.
- Which of the following is true about an RDS read replica configuration? (Choose two.)
Only three read replicas can be set up for a single primary database instance.
Only MariaDB, MySQL, and Aurora are supported.
A read replica replicates all databases in the primary instance.
A read replica can exist in a different region than the primary instance.
CD. You can have up to five read replicas at a time for a single instance
- You have a primary database set up to use read replicas running on an instance in US East 1. You have three read replicas also in US East 1 and two additional replicas in US West 2. You are trying to create a new replica in EU West 1 and are getting an error. What do you need to do to resolve this error and successfully create a new read replica in EU West 1?
Turn on the Multi-AZ option for your primary instance.
You can’t create the replica in EU West 1. Instead, create the replica in another US region to avoid regulations about read replicas in the EU.
Contact AWS about raising the number of read replicas allowed from 5 to 8.
Turn off one of the read replicas in US East 1 and then you can create the instance in EU West 1.
- D?. a read replica setup only allows for five read replicas. This is not a limit that can be raised by AWS either.暂时发现的唯一一个不能提ticket升的service
- Which of the following are true about a read replica setup? (Choose two.)
Backups are configured by default when you set up read replicas.
They provide a highly scalable solution for your on-premises databases.
They can exist within a single AZ, cross-AZ, or cross-region.
A read replica can be promoted to a stand-alone database instance.
CD。Read replicas are focused on performance, 跟disaster recovery无关。read replica 可以跨region
- Which of the following are true about a read replica setup? (Choose two.)
Automated backups are taken from the read replicas rather than the primary instance.
The database engine on all instances is active.
Each read replica instance can upgrade its database engine separate from the primary instance.
Replication is synchronous.
BC。No backups are taken from any instance automatically, including the primary instance,
- Which of the following statements are false? (Choose two.)
Both read replicas and Multi-AZ configurations ensure that you have database instances in multiple availability zones.
Both read replicas and Multi-AZ configurations provide disaster recovery options for your primary instance.
A single database can both have a read replica and be part of a Multi-AZ setup.
A read replica can be promoted to be a stand-alone database instance.
AB
- Which of the following statements is true?
A Multi-AZ setup is aimed at fault tolerance, while a read replica setup is aimed at scalability.
Both read replicas and Multi-AZ configurations are aimed at fault tolerance.
A Multi-AZ setup is aimed at scalability, while a read replica setup is aimed at fault tolerance.
Both read replicas and Multi-AZ configurations are aimed at scalability.
A
- Does a read replica provide any assistance at all in creating a fault-tolerant database setup?
Yes, it provides automated backups to the read replicas.
Yes, if the primary instance fails, one of the replicas can be manually promoted to a stand-alone database instance.
Yes, if the primary instance fails, one of the replicas will be automatically promoted to a stand-alone database instance.
No
B.While you get no automated backups or failover (A or C), you can manually promote a read replica instance to a stand-alone instance if you have to.
- Which of the following are valid reasons to use read replication? (Choose two.)
You have customers in a region geographically distant from your primary instance and want to improve their read performance when they access your applications hosted in regions closer to them.
Your current database instance is showing memory saturation with current traffic loads.
Your boss has asked for an automated backup solution that takes advantage of AWS managed services.
You need to perform additional OLTP queries and want to improve the performance of those queries.
AB
- How are automated backups related to read replicas?
They are not; read replicas and automated backups have no relationship at all.
Read replicas do not create automatic backups, but the primary database instance must have automatic backups enabled to create read replicas.
Read replicas cause the primary database instance to automatically begin backing up.
Each read replica is automatically backed up after an initial read from the primary database instance.
- B? read replicas are not a backup strategy, nor do they cause automatic backups to be set up. However, you must turn on automatic backups for the primary database instance to enable read replicas.
- Can a database instance be a read replica of one database and the source instance for another read replica?
Yes, as long as the source and replicant database are not the same instance.
No, a database cannot be both a read replica and a source database.
Yes, as long as the source and replicant database are in the same availability zone.
Yes, as long as you enable circular replication on both databases.
A. it is absolutely permissible for one database to replicate another database and then be the source for a third database.
- How quickly can you make changes to the backup window used by your RDS instance?
Changes to the window via the console take place within 1 hour; changes made via the API take place immediately.
Changes to the window take place after the next complete backup occurs.
Changes to the window via the API take place within 1 hour; changes made via the console take place immediately.
Changes to the window take place immediately.
D.There is no difference in response to a change in the backup window based on how that window is changed (API, console, etc.). All changes take place immediately.
- What is the longest backup retention window that Amazon RDS allows?
30 days
35 days
45 days
365 days
B? Amazon RDS backups can be retained for up to 35 days, and no longer.
- You have an Oracle installation using a custom geospatial plug-in. You also want to ensure the maximum throughput for database operations once those operations are begun by the plug-in. How would you set up Oracle to meet these requirements?
Set up Oracle using RDS with provisioned IOPS.
Set up Oracle using RDS with magnetic storage.
Install Oracle on an EC2 instance with a provisioned IOPS EBS volume.
Install Oracle on an EC2 instance with a magnetic EBS volume.
C
- In what scenarios would you install an Oracle database on an EC2 instance rather than using RDS? (Choose two.)
You want to use an ALB to support multiple instances and round-robin request distributions.
Your database size is greater than 80% of the maximum database size in RDS.
You have custom plug-ins that will not run in RDS.
You want to ensure that your database is only accessible through your private subnet in a VPC.
BC
- You launch an EC2 instance that has two volumes attached: a root and an additional volume, both created with default settings. What happens to each volume when you terminate the instance?
The root volume is deleted and the additional volume is preserved.
Both volumes are deleted.
Both volumes are preserved.
The instance is unable to terminate until the root volume is deleted.
A? root volumes are terminated on instance deletion, and by default, additional EBS volumes attached to an instance are not
- How many S3 buckets can you add to an account?
100
100 by default, but this can be increased by contacting AWS.
It depends on the default set for the new account by AWS.
It depends on how the account is configured at account creation.
B? The default for all new accounts is 100 allowed S3 buckets;
- What type of replication occurs in a Multi-AZ RDS setup?
Sequential replication
Synchronous replication
Asynchronous replication
Synchronous replication for full backups and asynchronous replication for incremental backups
B.Replication occurs synchronously from a primary instance to a secondary instance in a Multi-AZ setup.
- What type of replication occurs in a read replica RDS setup?
Sequential replication
Synchronous replication
Asynchronous replication
Synchronous replication for full backups and asynchronous replication for incremental backups
C? Replication occurs asynchronously from a primary instance to the various read replicas in a read replica setup
- Which of the following protocols and routing approaches does a classic load balancer support? (Choose two.)
IPv4
IPv6
HTTP/2
Registering targets in target groups and routing traffic to those groups
AB. Classic load balancers support both IPv4 and IPv6. They support HTTP/1 and HTTP/1.1, but only application load balancers support HTTP/2. Further, you must register individual instances, rather than target groups, with classic load balancers; registering target groups is a functionality only available with application load balancers.
- How many elastic IP addresses can you create per region by default in a new AWS account?
5
10
20
There is no preset limit.
A. AWS accounts allow you five elastic IP addresses per region by default.
- To how many EBS volumes can a single EC2 instance attach?
1
2
27
Unlimited
C.Officially, instances can have up to 28 attachments. One of those attachments is the network interface attachment, leaving 27 attachments available for EBS volumes
- Which of the following provide ways to automate the backup of your RDS database? (Choose two.)
Automated snapshots
S3 lifecycle management policies
Automated backups
Data pipeline
AC. RDS provides two (and only two) methods for backing up RDS databases at this point: automated backups and automated snapshots
- Your web-based application uses a large RDS data store to write and read user profile information. The latest marketing campaign has increased traffic to the application by an order of magnitude. Users are reporting long delays when logging in after having signed up. Which solutions are valid approaches to addressing this lag? (Choose two.)
Set up a Multi-AZ configuration for your RDS and round-robin requests between the two RDS instances to spread out traffic.
Employ ElastiCache to cache users’ credentials after their initial visit to reduce trips to the database from the web application.
Set up a read replica configuration for your RDS and round-robin requests between all the replicas to spread out traffic.
Increase the number of EC2 instances allocated to your Auto Scaling group to spread out traffic on the web application tier.
BC
- In which of the following situations would you recommend using a placement group?
Your fleet of EC2 instances requires high disk IO.
Your fleet of EC2 instances requires high network throughput across two availability zones.
Your fleet of EC2 instances requires high network throughput within a single availability zone.
Your fleet of EC2 instances requires high network throughput to S3 buckets.
C. A placement group is concerned primarily with network throughput and reducing latency among EC2 instances within a single availability zone.
- Which of the following statements are true about cluster placement groups? (Choose two.)
All instances in the group must be in the same availability zone.
Instances in the group will see lowered network latency in communicating with each other.
Instances in the group will see improved disk write performance when communicating with S3.
Instances in the group must all be of the same instance class.
AB
- Which of the following statements are true about spread placement groups? (Choose two.)
All instances in the group must be in the same availability zone.
Instances in the group will see lowered network latency in communicating with each other.
You can have up to seven instances in multiple availability zones in the group.
AWS provisions the hardware rather than having you specify the distinct hardware for the group.
bc? Spread placement groups can span availability zones and support up to seven instances per zone
- Where is data stored when placed into S3-IA? (Choose two.)
In the region specified at bucket creation
In a special AWS “global” region for S3 storage
In at least three availability zones
In a single availability zone within at least three regions
ac? All S3 and S3-IA data is stored in a single region and within at least three availability zones within that region.
- You need to perform a large amount of OLAP. Which AWS service would you choose?
DynamoDB
RDS Aurora
Redshift
Oracle installed on EC2 instances
C
- What is the maximum allowable RDS volume size when using provisioned IOPS storage?
8 TB
16 TB
12 TB
1 PB
b? All the major databases supported by RDS—MariaDB, SQL Server, MySQL, Oracle, and PostgreSQL—allow up to 16 TB of storage for a provisioned IOPS volume.
- Which of the following is a valid reason to use a cold HDD EBS volume?
You need a performant solid-state drive.
You are trying to choose the lowest-cost EBS volume possible.
You are performing data warehousing using the volume.
You need an inexpensive boot volume.
b? A cold HDD is not available to be used as a boot volume.
- Which of the following are available to use as an EBS boot volume? (Choose two.)
General SSD
Cold HDD
Throughput optimized HDD
Provisioned IOPS
ad? HDD不能做boot volumes
- Which of the following is a valid reason to use a General Purpose SSD EBS volume? (Choose two.)
You need to support large database workloads.
You want a blend of a performant SSD and a cost-sensitive SSD volume.
You are performing data warehousing using the volume.
You have low-latency apps and want to run them on a bootable volume.
BD
- Which of the following is a valid reason to use a provisioned IOPS EBS volume? (Choose two.)
You want a low-cost option for your EBS volume.
You need to support a large MongoDB database workload.
You need massive performance and throughput for your applications.
You have applications that need a bootable environment but can fail from time to time and be re-created.
BC
- Which of the following are characteristics of SSD-backed volumes? (Choose two.)
Transactional workloads
Streaming workloads
Small I/O size
Throughput-focused
AC.An SSD volume is best for transactional workloads (A) with a large number of small I/O sized read/write operations.
- Which of the following are characteristics of HDD-backed volumes? (Choose two.)
Transactional workloads
Streaming workloads
Small I/O size
Throughput-focused
BD.An HDD-backed volume is best for streaming workloads where throughput needs to be maximized over IOPS.
- You are charged with installing Oracle on a fleet of EC2 instances due to custom Java-based plug-ins you need to install along with Oracle. Which EBS volume type would you choose to best support your Oracle installation?
Magnetic
Throughput-optimized HDD
Provisioned IOPS SSD
General SSD
C
- You are the solutions architect for a company installing a web application on a set of EC2 instances. The application writes a small amount of user profile data to attached EBS volumes, and accesses that data an average of once every five minutes if the user is still using the web application. Additionally, because of the high cost of the application’s RDS instance, you would like to minimize your EBS volume costs. Which EBS volume type would you choose to support these applications?
Magnetic
Throughput-optimized HDD
Provisioned IOPS SSD
General SSD
A
- Which of the following can be an EBS boot volume? (Choose two.)
Magnetic
Throughput-optimized HDD
Provisioned IOPS SSD
Cold HDD
ac. You can boot an EC2 instance off any SSD type, as well as the magnetic type.
